The _^<a!T34855_wheel_^>a_ is a mechanical device which provides rotary motion by means of a disk or circular frame revolving on an axis. The earliest known form is a two-wheeled cart of the _^<a!T4854_Bronze Age_^>a_ (4000 BC) in _^<a!T31380_Sumer_^>a_, _^<a!T21727_Mesopotamia_^>a_. The rotary motion provided by the wheel is so basic to machinery that it is doubtful that mechanized civilization could have developed without it._^<g_See also: _^<a!T18457_Kish_^>a_; _^<a!T26389_potter's wheel_^>a_; _^<a!T33526_Ur_^>a_; _^<a!T33573_Uruk_^>a_._^<g_
The word _^<i_civilization_^>i_ originally meant _^<i_living in cities_^>i_. In _^<a!T21727_Mesopotamia_^>a_, "the land between the two rivers," Sumerians began to build the world's first cities (_^<i_c._^>i_3500 BC). The people in these flourishing Mesopotamian cities depended on irrigation; skilled craftsmen using metal; and a complex system of government including tax collectors, scribes, and priests. Commerce grew, along with the need to record business transactions, and the art of writing was first developed in _^<a!T31380_Sumer_^>a_ (_^<i_c._^>i_3300 BC). Sumerians were using sailboats, wheeled vehicles, and animal-drawn plows by 3000 BC. Alexander the Great's conquest (539 BC) ended this early civilization._^<g_See also: _^<a!T1164_Amorites_^>a_; _^<a!T2434_Babylon_^>a_; _^<a!T18099_Kassites_^>a_; _^<a!T22167_Mitanni_^>a_; _^<a!T23307_Nebuchadnezzar II_^>a_; _^<a!T35444_writing systems, evolution of_^>a_._^<g_
From 1792 to 1750 BC, _^<a!T14970_Hammurabi_^>a_ of Babylon ruled _^<a!T21727_Mesopotamia_^>a_. During his reign, Hammurabi promulgated the first legal code. A capable administrator and a successful warrior, Hammurabi conquered rivals in the last decade of his reign and established and extended the Mesopotamian state. His kingdom reflects the first golden age of Semitic culture in the Near East. Guided by such principles as: "The strong should not injure the weak" and "The punishment should fit the crime," the _^<a!T14969_Code of Hammurabi_^>a_ had 282 legal provisions, systematically arranged and relating to family, labor, personal property, real estate, trade, and business._^<g_See also: _^<a!T1164_Amorite_^>a_; _^<a!T2435_Babylonia_^>a_._^<g_
_^<a!T758_Alexander the Great_^>a_ took up the war against the Persian Empire when he became king of Macedonia following his father's assassination. In 333 BC Alexander met and defeated the army of _^<a!T8975_Darius III_^>a_ at Issus (near modern Iskenderun, Turkey). In the autumn of 331 BC Alexander became the legitimate king of Persia after defeating Darius' grand army at Gaugamela (near modern Irbil, _^<a!T17107_Iraq_^>a_). Although his life became wreathed in legend following his death, it seems clear that Alexander was a military genius and a successful opportunist._^<g_The Persian Empire is said to have existed from 549 BC when _^<a!T8797_Cyrus the Great_^>a_ defeated the Median king, Astyages, until 330 BC when Darius III, who had been defeated twice by Alexander the Great, was murdered by his own followers._^<g_See also: _^<a!T25487_Persia, ancient_^>a_._^<g_
Early in the 5th century AD, _^<a!T7018_Christianity_^>a_ reached _^<a!T17110_Ireland_^>a_. It had become the religion of the Holy Roman Empire a century earlier. The patron saint and apostle of Ireland is _^<a!T25141_Patrick_^>a_, who was born in western Britain. In AD 432 Patrick was appointed bishop of Ireland. He then set about making converts and securing toleration for Christians. Patrick established Irish dioceses, held church councils, developed a native clergy, and fostered the growth of _^<a!T22334_monasticism_^>a_. In modern Ireland, 94% of the people are Roman Catholic._^<g_See also: _^<a!T22069_ministry, Christian_^>a_._^<g_
One of the world's earliest civilizations, that of ancient _^<a!T10685_Egypt_^>a_ (_^<i_c._^>i_ 3100 BC to AD 639), remains significant and important today for a number of reasons. A long, continuous record tells us much about Egyptian art, architecture, religion, and everyday life. Egyptians were a happy, optimistic, and conservative people. An awareness and love of nature were very much a part of their lives._^<g_In ancient Egypt the king controlled everything, including the administration, the army, and the economy. The Old Kingdom, the Middle Kingdom, and the New Kingdom were the three periods of high achievement in the history of ancient Egypt. It was not until the late reigns of the New Kingdom that _^<i_Pharaoh_^>i_ ("great house") was used to designate the king._^<g_The influence of the early Egyptians extended well beyond their borders, into _^<a!T14335_Greece_^>a_, _^<a!T28008_Rome_^>a_, Syria-Palestine, and the ancient kingdoms of the _^<a!T31317_Sudan_^>a_._^<g_The Western alphabet we use is derived from a Phoenician one which may have been modeled on Egyptian _^<a!T15753_hieroglyphics_^>a_. Developments in _^<a!T1695_archaeology_^>a_ and historical writing have made the civilization of ancient Egypt accessible to the general public today._^<g_See also: _^<a!T10686_Egypt, ancient_^>a_; _^<a!T10692_Egyptology_^>a_; _^<a!T14336_Greece, ancient_^>a_; _^<a!T28010_Rome, ancient_^>a_; _^<a!T35444_writing systems, evolution of_^>a_._^<g_
The term _^<i_pyramid_^>i_ in architecture denotes a monument resembling the geometrical figure of the same name. Classical Egyptian _^<a!T26909_pyramids_^>a_--funerary monuments built for the rulers, the _^<a!T25602_pharaohs_^>a_, and their closest relatives--shared a common feature, a temple complex. At _^<a!T13737_Giza_^>a_ (which today is a prosperous suburb of Cairo, _^<a!T10685_Egypt_^>a_), the most elaborate example of this temple complex may be seen. The Great Sphinx and the three large pyramids of kings _^<a!T18322_Khufu_^>a_ (Cheops), _^<a!T18292_Khafre_^>a_, and _^<a!T21627_Menkaure_^>a_, rulers of the 4th dynasty, built between 2613 and 2494 BC, are located some 8 km (5 mi) southwest of Giza. Many modern tourists visit the Giza pyramids, one of the Seven Wonders of the Ancient World._^<g_See also: _^<a!T10692_Egyptology_^>a__^<g_
_^<a!T28010_Rome_^>a_ annexed _^<a!T10685_Egypt_^>a_ after a crucial naval battle took place between Mark _^<a!T1525_Antony_^>a_ and Octavian in the Ionian Sea off _^<a!T223_Actium_^>a_ (31 BC). At the time of this battle the Roman world was ruled by Antony and _^<a!T7335_Cleopatra_^>a_ in the east and by Octavian in the west. By defeating the army and fleet of Antony and Cleopatra, Octavian won mastery of the Roman world. Egypt then was governed by a prefect as the personal estate of Octavian who, as emperor, was known as _^<a!T2221_Augustus_^>a_._^<g_
An early Semite civilization in the _^<a!T21900_Middle East_^>a_ was that of the Phoenicians and the Hebrews, dating from _^<i_c._^>i_ 3000 BC._^<g_Among the _^<a!T29374_Semites_^>a_, Phoenicians excelled as traders and sailors and founded their great city of _^<a!T6034_Carthage_^>a_ in the 8th century BC. The _^<a!T5636_Canaanite civilization_^>a_ reached its height at _^<a!T5324_Byblos_^>a_, a wealthy Phoenician seaport and trade center, where alphabetic (Phoenician) writing was developed._^<g_The Hebrews, a people of fierce religious faith, believed in and worshipped a single God; their faith became the Jewish faith, and later the Christian faith arose among them._^<g_After the destruction of _^<a!T17544_Jerusalem_^>a_ by the Romans in AD 135 and the consequent enslavement and dispersion of the inhabitants throughout the Mediterranean world, the whole of Judaea was renamed _^<a!T24816_Palestine_^>a_._^<g_See also: _^<a!T7018_Christianity_^>a_; _^<a!T17845_Judaism_^>a_; _^<a!T25697_Phoenicia_^>a_._^<g_
For 500 years (from _^<i_c._^>i_ 2600 BC), _^<a!T5324_Byblos_^>a_, an ancient city of _^<a!T25697_Phoenicia_^>a_, was the most important city in the eastern Mediterranean world. Alphabetic or Phoenician writing was first practiced in Byblos where _^<a!T24940_papyrus_^>a_ scrolls were used and _^<i_biblia_^>i_ (books) were made from papyrus. Phoenician writing differed both from _^<a!T8660_cuneiform_^>a_ or wedge-shaped writing and from Egyptian _^<a!T15753_hieroglyphics_^>a_. A writing system with a sign for each sound of the language is called _^<i_alphabetic_^>i_. It offers a good compromise between economy and explicitness._^<g_See also: _^<a!T35444_writing systems, evolution of_^>a_._^<g_
_^<a!T17553_Jesus Christ_^>a_ lived, according to the latest archaeological evidence, from 6 BC to AD 30 in the Jewish milieu of 1st-century _^<a!T24816_Palestine_^>a_. He founded _^<a!T7018_Christianity_^>a_, one of the world's major _^<a!T27480_religions_^>a_. Christians claim that God sent Jesus Christ to save all people and that he is the _^<a!T21741_messiah_^>a_ foretold in the prophecies of the Hebrew _^<a!T3610_Bible_^>a_ (to Christians, the Old Testament). Early Christians called themselves followers of "The Way," which quickly spread throughout the Mediterranean world. In the fourth century Christianity became the official religion of the Roman Empire. Today about a billion people all over the world call themselves Christians._^<g_See also: _^<a!T26686_Protestantism_^>a_; _^<a!T27984_Roman Catholic church_^>a_._^<g_
The _^<a!T24299_Olmec_^>a_ people of ancient Mexico developed the "mother civilization" of _^<a!T6345_Central America_^>a_. Three basic characteristics of Middle American civilizations are believed to have come from the Olmecs: 1) extensive trade; 2) monumental architecture, including _^<a!T26909_pyramids_^>a_; and 3) worship of a god concerned with rain and fertility.The Olmecs were the first people of North America to build religious structures with pyramids. The decline of the Olmec civilization dates from the destruction of their religious center at _^<a!T18831_La Venta_^>a_ (_^<i_c._^>i_ 400 BC)._^<g_See also: _^<a!T21817_Mexico, history of_^>a_._^<g_
Three important early civilizations developed in the Americas: those of the _^<a!T21406_Maya_^>a_, the _^<a!T2393_Aztecs_^>a_, and the _^<a!T16773_Incas_^>a_. Many elements of these cultures live on in their descendants even to this day._^<g_The first people of the New World to keep historical records were the Maya, a group of American Indian peoples. Mayan history records the reigns of great kings and queens, from _^<i_c._^>i_ 50 BC until the Spanish conquest in the 16th century AD; their history has been found inscribed on pots, jades, bones, stone monuments, and palace walls._^<g_From a small, nomadic tribe came the Aztecs, who reached the peak of their power in the 15th century when Montezuma I expanded the empire from the Atlantic to the Pacific. Aztec Mexico, with customs and technology unlike those of the Old World, was rich, civilized, and sophisticated. In 1521, when _^<a!T22446_Montezuma II_^>a_ ruled the empire, _^<a!T8214_Cortes_^>a_ captured the capital at _^<a!T32093_Tenochtitlan_^>a_ and ended Aztec dominion._^<g_The largest native empire in the Americas was that of the Incas, which lasted for just a brief time. In 1438 _^<a!T24723_Pachacuti_^>a_ became the ruler, Sapa Inca, and began to expand the state. The greatest expansion took place during the rule of Topa Inca (r. 1471-93). The Incas were notable both for social and economic planning and for engineering skill. In 1532 Francisco _^<a!T25941_Pizarro_^>a_, with a band of Spanish _^<a!T7927_conquistadors_^>a_, conquered and abruptly ended the Inca Empire_^<g_
During the Mayan Classical Period (AD 292-909), _^<a!T21406_Maya_^>a_ rulers reigned over a time of great cultural achievement, craft specialization, and population growth. Archaeological evidence that Tikal, in the Guatemalan lowlands, and other sites were actually urban centers contradicts the earlier view of the Maya as a "civilization without cities."_^<g_See also: _^<a!T21817_Mexico, history of_^>a_._^<g_
Developments in the _^<a!T348_Aegean civilization_^>a_ of the Minoans and the Mycenaeans gave rise to the classical age of Greece._^<g_The Minoan civilization is named after King _^<a!T22094_Minos_^>a_, recorded in Greek tradition as a prehistoric king of _^<a!T8475_Crete_^>a_. Cretans developed a kind of writing, Linear A. Natural disasters, including the cataclysmic eruption of the volcano of _^<a!T32258_Thera_^>a_ (_^<i_c._^>i_ 1500 BC) and the tidal wave that followed, contributed to the collapse of Minoan civilization._^<g_The Mycenaeans, who had established themselves in mainland Greece several centuries earlier, took over the Aegean islands and occupied Crete. Mycenaean writing, _^<a!T19762_Linear B_^>a_, has been found on clay tablets. Mycenaean dominance lasted until the 12 century BC, when it collapsed due to reasons that remain mysterious. Four centuries later the poet _^<a!T16025_Homer_^>a_ immortalized Mycenaean heroes who had been kept alive by oral tradition (see _^<a!T24159_Odysseus_^>a_; _^<a!T182_Achilles_^>a_; _^<a!T23404_Nestor_^>a_; and _^<a!T434_Agamemnon_^>a_)._^<g_See also: _^<a!T4854_Bronze Age_^>a_; _^<a!T18535_Knossos_^>a_; _^<a!T22972_Mycenae_^>a_; _^<a!T35444_writing systems, evolution of_^>a_._^<g_
The largest Greek island, mountainous _^<a!T8475_Crete_^>a_, lies between southern Greece and Turkey. Settled between 3000 and 2500 BC, Crete was the center of an important _^<a!T4854_Bronze Age_^>a_ culture called _^<i_Minoan_^>i_ (named for the legendary King _^<a!T22094_Minos_^>a_). The Minoans built elaborate settlements and palaces, notably at _^<a!T18535_Knossos_^>a_ and _^<a!T25592_Phaistos_^>a_. Crete played an important role in the transmission of ancient Near Eastern civilization to Europe._^<g_See also: _^<a!T348_Aegean civilization_^>a_; _^<a!T22086_Minoan art_^>a_._^<g_
Ancient Greece (from _^<i_c._^>i_2200 BC) laid the foundation for the culture of the Western world. Arts, building, science, and _^<a!T25683_philosophy_^>a_ were among the areas of Greek achievement. Balance and harmony were their guiding principles. The Greeks loved beauty and stressed the importance of language. _^<a!T9363_Democracy_^>a_ arose in Greece along with the idea of the importance of the individual possessing dignity and rights._^<g_A great wave of colonization from 750 BC to 500 BC spread Greek culture throughout the Mediterranean and even into the southern _^<a!T33356_Ukraine_^>a_. The great city-states of _^<a!T2114_Athens_^>a_ and _^<a!T30584_Sparta_^>a_ emerged as major powers in the 6th century BC._^<g__^<a!T758_Alexander the Great_^>a_ initiated the systematic Hellenization of the East. In 338 BC three centuries of Greek-inspired civilization, the _^<a!T15475_Hellenistic Age_^>a_, began. _^<a!T28008_Rome_^>a_ became the decisive factor in Greek affairs after 200 BC. Soon after the Roman conquest of _^<a!T6034_Carthage_^>a_ (146 BC), mainland Greece became a Roman protectorate. The stronger cultural influence, however, was Greece, as the Roman lyric poet _^<a!T16135_Horace_^>a_ wrote: "Captive Greece made captive her rude conqueror." In AD 324 Greece was subsumed into the Byzantine Empire._^<g_See also: _^<a!T14336_Greece, ancient_^>a_; _^<a!T15472_Hellenism_^>a_ _^<a!T28010_Rome, ancient_^>a_._^<g_
The myths of ancient _^<a!T17427_Japan_^>a_ and the findings of archaeologists and anthropologists have been pieced together to tell us what we know about the first peoples to inhabit the Japanese archipelago._^<g_A new culture claiming descent from the sun goddess, the Yamato clan, appeared in Japan _^<i_c._^>i_AD 300. By the mid-4th century Yamato rulers had achieved political unity. A centralized political structure evolved in which the sovereign, relying upon the advice of "spokesmen chiefs," presided over the court. Pottery, figurines, armor, jewelry, weapons, and other evidence portraying Yamato leaders as mounted warriors with long iron swords and bows have been found in their massive tombs. In AD 604, a constitution introducing the Confucian conception of a state was promulgated by the regent Prince _^<a!T29775_Shotoku Taishi_^>a_._^<g_See also: _^<a!T17428_Japan, history of_^>a_._^<g_
_^<a!T17427_Japan_^>a_, an Asian island nation with a long and varied history, was founded more than 2,000 years ago and is the oldest monarchy in the world. The name _^<i_Japan_^>i_ is based on the Chinese reading of the name _^<i_Nihon_^>i_ or _^<i_Nippon_^>i_, which means "land of the rising sun." Though it encouraged the development of independent communities, the beautiful mountainous terrain of Japan made national unity difficult._^<g_Reliable chronicles of Japanese history date from the 5th century AD. European traders knew the islands of Japan in eastern Asia during the 15th century. Japan developed a highly original and distinctive culture during the Tokugawa period (1603-1867), an era of isolation. The country reopened contact and trade with the outside world under the _^<a!T21539_Meiji Restoration_^>a_ (1868-1912). Although Japan possesses few raw materials, it has developed into one of the world's leading industrialized nations._^<g_See also: _^<a!T17428_Japan, history of_^>a_; _^<a!T32644_Tokugawa, family_^>a_._^<g_
According to legend, _^<a!T28018_Romulus_^>a_ and _^<a!T28018_Remus_^>a_, twin brothers who were descendants of _^<a!T359_Aeneas_^>a_, founded the city of _^<a!T28008_Rome_^>a_ in 753 BC. Thus began the process which led to an empire encompassing all of the Mediterranean world._^<g__^<a!T28010_Ancient Rome_^>a_'s history has three divisions: the kingship, spanning from its legendary founding to 509 BC; the republic, ruled by the aristocracy (509 BC to 31 BC); and the empire, wherein a compromise between monarchy and republican government evolved and survived until the fall of Rome in AD 476._^<g_The first Roman emperor, Octavian, who was known as _^<a!T2221_Augustus_^>a_, ushered in a 200-year era of peace, known as the _^<i_Pax Romana_^>i_. Forms of Roman civilization appeared everywhere--roads (more than 60,000 miles), bridges, aqueducts, and, most of all, cities. A population of skilled farmers and artisans supported the structure. The six Antonine emperors ruled from AD 96 to 180, the "Golden Age" of the Roman Empire. After this period, the empire began to decline._^<g_Rome's unrivaled cultural legacy to the modern world, the basis of Western civilization, includes the best of Greek culture, which it absorbed and passed on, and the Roman respect for law and a sense of discipline. _^<g_See also: _^<a!T1523_Antoninus Pius_^>a_; _^<a!T27990_Roman roads_^>a_. _^<g_
Octavian, Caesar's grandnephew and heir, became the first Roman emperor in 27 BC and took the name Imperator Caesar _^<a!T2221_Augustus_^>a_. During his reign the Roman Empire was at its height, and the 200 years of peace known as the _^<i_Pax Romana_^>i_ began. Augustus established a stable system of government with machinery that functioned efficiently on its own. The emperor became a great patron of the arts; significant contributors to Latin literature were the poets Vergil, Horace, and Ovid and the historian Livy. Augustus died in AD 14._^<g_See also: _^<a!T28010_Rome, ancient_^>a_._^<g_
The Antonine emperors ruled over what is sometimes called the "Golden Age of the Roman Empire" (AD 96 to 180). A Spaniard and the first non-Italian to serve as emperor, _^<a!T32835_Trajan_^>a_ ruled from 98 to 117 and built impressive aqueducts, roads, theaters, and basilicas. His successor, _^<a!T14803_Hadrian_^>a_, overhauled the imperial finances and made important reforms in the administration of justice. The "Golden Age," though, was marked economically by an increasing disparity between the rich and the poor._^<g_See also: _^<a!T10480_Early Christian art and architecture_^>a_; _^<a!T21013_Marcus Aurelius_^>a_; _^<a!T28010_Rome, ancient_^>a_._^<g_
In AD 395 the Roman Empire was permanently divided into the Latin Western and the Greek Eastern or _^<a!T5344_Byzantine Empire_^>a_. In succeeding decades, the Western Empire was gradually overrun and dismembered by various Germanic tribes. In 410 the Visigoths and in 455 the _^<a!T33726_Vandals_^>a_ plundered the city of _^<a!T28008_Rome_^>a_. Finally in 476, when the German general, _^<a!T24154_Odoacer_^>a_, forced the last emperor of the west, the child Romulus Augustulus, to abdicate, the history of ancient Rome ingloriously ended._^<g_See also: _^<a!T14088_Goths_^>a_; _^<a!T28010_Rome, ancient_^>a_._^<g_
The _^<a!T5344_Byzantine Empire_^>a_ identifies the continuation of the eastern part of the Roman Empire, which flourished in the eastern Mediterranean for more than 1,000 years (AD 324-1453). Using _^<a!T14341_Greek_^>a_ as its principal language, the empire was grounded in the Christian-imperial idea that this chosen people were ordained to rule and to preserve universal peace._^<g_The empire's history may be divided into three periods: Early (_^<i_c._^>i_370-570), when the chief threat was invasion by barbarians; Middle (early-7th to early-11th century), when the empire was reduced to governing only Asia Minor, although from the 9th to the 11th century it was the strongest and richest state in the Western world; and Late (_^<i_c._^>i_1025-1453), the period of Byzantium in slow decline._^<g_In 324, _^<a!T7964_Constantine I_^>a_ began to rebuild the city of Byzantium, made it the new capital, and renamed it Constantinople (now _^<a!T17238_Istanbul_^>a_). The fall of the city to the Ottoman sultan _^<a!T21533_Mehmed II_^>a_ in 1453 marked the empire's end._^<g_See also: _^<a!T5343_Byzantine art and architecture_^>a_; _^<a!T8588_Crusades_^>a_; _^<a!T10480_Early Christian art and architecture_^>a_; _^<a!T28010_Rome, ancient_^>a_._^<g_
The _^<a!T23369_Neolithic Period_^>a_ or "New Stone Age" profoundly changed people's lives through the introduction of farming and the domestication of animals. Women and men continued to hunt, to fish, and to gather wild fruit and nuts, but the production of food became more important than collecting it. The more-settled existence necessary for farming transformed early societies; a new way of life and of thinking found people planning for the future, constructing substantial houses and villages, and evolving new social customs. Also significant for this period were the use of ground and polished stone tools and the manufacture of pottery._^<g_A large series of cultures developed in different parts of the world, as is evidenced in such archaeological finds as pottery and stone vessels, houses and settlement plans, and ritualistic paraphernalia._^<g_See also: _^<a!T1695_archaeology_^>a_; _^<a!T6146_Catal Huyuk_^>a_; _^<a!T11407_European prehistory_^>a_; _^<a!T11718_farms and farming_^>a_; _^<a!T11909_Fertile Crescent_^>a_._^<g_
_^<a!T8718_Cush_^>a_, or Kush, the ancient kingdom of Nubia in North Africa, was first mentioned in Egyptian writings _^<i_c._^>i_1950 BC when it stood between the second and third cataracts of the Nile in what is now Sudan. Cush conquered Upper _^<a!T10685_Egypt_^>a_ during the 8th century BC and set up a capital at Napata. The Cushites, descendants of Sudanese-Saharan peoples, developed a civilization quite different from that of Egypt. In the 6th century BC the Cushite capital was moved upstream to _^<a!T21698_Meroe_^>a_. From _^<i_c._^>i_300 BC Cush was an important ironworking region. The state flourished until AD _^<i_c._^>i_350, when it was sacked by Christians from Aksum (Ethiopia)._^<g_See also: _^<a!T397_Africa, history of_^>a_._^<g_
Archaeological studies confirm that from _^<i_c._^>i_500 BC to AD _^<i_c._^>i_200, agricultural settlements of the Nigerian Nok culture existed in _^<a!T34794_West Africa_^>a_. There is evidence that the Nok people mined and smelted iron. Celebrated Nok terra-cottas, the oldest sculptures of sub-Saharan Africa, exhibit the artistic talent of this early African civilization. Nok culture was an early part of present-day _^<a!T23652_Nigeria_^>a_, which possesses an artistic and cultural heritage unsurpassed in sub-Saharan Africa._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T405_African art_^>a_; _^<a!T32131_terra-cotta_^>a_._^<g_
_^<a!T396_Africa_^>a_, the second largest continent after Asia, is bounded by the Atlantic Ocean on the west and the Indian Ocean on the east and covers 11.5 million square miles. If you look at a globe or a world map you will see that no continent lies as close to all the others as Africa does._^<g__^<a!T413_African prehistory_^>a_ encompasses the vast span of time before written history began. More than 90 percent of what we now know about human origins has come from Africa._^<g_Great civilizations and kingdoms developed in Africa: ancient _^<a!T10685_Egypt_^>a_ in the north from the 4th millennium BC; the kingdoms of _^<a!T13564_Ghana_^>a_, _^<a!T20793_Mali_^>a_, _^<a!T18017_Kanem-Bornu_^>a_, and _^<a!T30423_Songhai_^>a_ during the Middle Ages; the kingdoms of _^<a!T1971_Ashanti_^>a_, _^<a!T3363_Benin_^>a_, _^<a!T18591_Kongo_^>a_, Oyo and Dahomey further south in the rain forests from the 14th century AD; the kingdoms in east central Africa of Ankole, Buganda, Bunyoro, _^<a!T20168_Luba_^>a_, and _^<a!T20252_Lunda_^>a_._^<g_Until the Portuguese established trading stations on the coast in the 15th and 16th centuries, little was known of Africa to the outside world. In the 19th century Europeans arrived to explore or colonize and, by the early 20th century, European colonial powers had partitioned most of the continent among themselves. Many African nations have gained independence since World War II. Africa's diversity is evident in the different races, languages, religions, and ways of conducting politics that exist today._^<g_See also: _^<a!T10686_Egypt, ancient_^>a_; _^<a!T26479_prehistoric humans_^>a_; _^<a!T30103_slavery_^>a_; _^<a!T33345_Uganda_^>a_. _^<g_
The _^<a!T29578_Shang_^>a_ dynasty in China, traditionally dated from _^<i_c._^>i_1766 BC to 1122 BC, was characterized by an advanced system of writing (still in use today), a sophisticated bronze _^<a!T21754_metallurgy_^>a_, the growth of cities, and the first Chinese _^<a!T5473_calendar_^>a_ (something very important to an agricultural society). The Shang had evolved, in ways which are still unclear, out of the earlier cultures of the Yangshao and Longshan, who are known for their distinctive pottery. According to one tradition, the Shang civilization marks the beginning of China's _^<a!T4854_Bronze Age_^>a_ as well as of its history proper._^<g_See also: _^<a!T6873_China, history of_^>a_; _^<a!T35444_writing systems, evolution of_^>a_. _^<g_
Against the dangerous nomads from the north and the west, Shi Huangdi, the first _^<a!T26943_Qin_^>a_ (Ch'in) emperor, linked the earlier walls of individual states to create a solid barrier from the sea to the desert along China's northern mountains. This original _^<a!T14326_Great Wall of China_^>a_, the longest such fortification ever built, extended 1,500 miles (2,400 km) from the Yellow Sea, along the edge of the Mongolian plateau, to western Gansu (Kansu) province._^<g_See also: _^<a!T6873_China, history of_^>a_._^<g_
_^<a!T6872_China_^>a_, the third-largest country in the world and the most populous, is located in East Asia._^<g_Prehistoric human fossils found in China show that some of our very early ancestors probably lived there. The best-known may be Beijing man (_^<a!T25279_Peking man_^>a_), skeletal remains of which were discovered in a limestone cave southwest of Beijing in 1927._^<g_The name _^<i_China_^>i_ is derived from the _^<a!T26943_Qin_^>a_ (Ch'in) dynasty. Under Shih Huang Ti (The First August Sovereign) the Q'in (221-206 BC) established the first centralized imperial administration in China. The Q'in standardized coinage, weights and measures, the Chinese writing system, and the calendar. Defenses were strengthened and the _^<a!T14326_Great Wall of China_^>a_ was created._^<g_During the _^<a!T14985_Han_^>a_ dynasty (202 BC to AD 220), the Chinese invented paper and the water-powered mill, and Indian _^<a!T5060_Buddhism_^>a_ was transformed into a Chinese religion. A truly remarkable cosmopolitanism developed during the _^<a!T31774_Tang_^>a_ dynasty (AD 618-906). In 1279, _^<a!T18723_Kublai Khan_^>a_, the grandson of _^<a!T13409_Genghis Khan_^>a_, conquered China for the Mongols and began the _^<a!T35714_Yuan_^>a_ dynasty. The Manchus (1644-1911) replaced the _^<a!T22058_Ming_^>a_ dynasty (1368-1644)._^<g_Since 1949, when the Chinese Communists took power, the official name for the country has been the People's Republic of China._^<g_
One of the world's oldest and greatest civilizations took shape between 3000 BC and 2500 BC in the valley of the _^<a!T16850_Indus_^>a_ River, from which the name of the Indian subcontinent is taken. Remains of more than 100 cities, towns, and villages of the Indus, or Harappa, civilization have been found. Each city was laid out on a grid plan and had an elaborate public drainage system. Abundant remains have been found, including gold _^<a!T17563_jewelry_^>a_, _^<a!T32131_terra-cotta_^>a_ figurines, and small sculptures of stone and _^<a!T4853_bronze_^>a_. The Indus Valley civilization dates to _^<i_c._^>i_1700 BC._^<g_See also: _^<a!T10115_drainage systems_^>a_; _^<a!T16799_India_^>a_; _^<a!T16851_Indus civilization_^>a_; _^<a!T29215_sculpture_^>a_. _^<g_
Harappa culture thrived until _^<i_c._^>i_1500 BC, when nomadic _^<a!T1944_Aryan_^>a_ invaders pushed through the northwest passes into the Punjab and overran the _^<a!T16850_Indus_^>a_ Valley. What we know about these early Indo-Aryans comes from the _^<i_Rig Veda_^>i_ ("Verses of Knowledge"), a collection of hymns written in an early form of Sanskrit. Here a system of _^<i_varnas_^>i_, or classes, is mentioned (from which evolved India's _^<a!T6112_caste_^>a_ system). Eventually their religion and way of life was modified by the processes of absorption and developed into Hinduism._^<g_See also: _^<a!T16799_India_^>a_; _^<a!T16836_Indo-Iranian languages_^>a_; _^<a!T16851_Indus civilization_^>a_._^<g_
_^<a!T5060_Buddhism_^>a_, one of the major religions of the world, was founded by Siddhartha ("he who will accomplish") Gautama, the _^<a!T5059_Buddha_^>a_, who lived in northern _^<a!T16799_India_^>a_ from _^<i_c._^>i_560 to _^<i_c._^>i_480 BC. Buddha's original teaching began _^<i_c._^>i_525 BC. Although its content is still a matter of debate, this teaching may have contained the Four Noble Truths or central doctrines: suffering or _^<i_duhkha_^>i_, the cause of suffering, the end of suffering or _^<a!T23713_nirvana_^>a_ and the way to the cessation of suffering or the Eightfold Path._^<g_See also: _^<a!T18080_karma_^>a_; _^<a!T27480_religion_^>a_._^<g_
The world's second-most-populous nation (after China) and the seventh-largest in area, _^<a!T16799_India_^>a_ is located in South Asia on the Indian subcontinent. The name _^<i_India_^>i_ was used by the ancient Greeks and Persians and derives from the _^<a!T16850_Indus_^>a_ River. Possessing a rich heritage from the past, the people of India today hope for the ideal of its modern leaders: a future of prosperity in a world where peace prevails._^<g_Indian culture is of great antiquity. The earliest Indian civilization grew up in the Indus Valley from 4000 to 2500 BC; only in the 20th century, however, did archaeologists discover remains which began to illuminate its history._^<g_Religion has played an important role in the life of India. _^<a!T15818_Hinduism_^>a_, _^<a!T5060_Buddhism_^>a_, and _^<a!T17372_Jainism_^>a_ began in ancient India. _^<a!T17192_Islam_^>a_ strongly affected the culture of India, beginning in the 11th century and continuing under the Mogul Empire (established by _^<a!T2432_Babur_^>a_ in 1526). In the 18th century after years of Anglo-French conflict, the subcontinent was absorbed piecemeal into the _^<a!T4784_British Empire_^>a_, the local princes and rulers retaining some of their autonomy._^<g_National rule began when India became independent in 1947, and Prime Minister Jawaharlal _^<a!T23332_Nehru_^>a_ told the people of India: "A moment comes, which comes but rarely in history, when we step out from the old to the new, when an age ends, and when the soul of a nation, long suppressed, finds utterance." At that time the two northern regions of India became the separate state of _^<a!T24786_Pakistan_^>a_. In 1971 East Pakistan became the separate nation of _^<a!T2686_Bangladesh_^>a_._^<g_Today India is the world's largest democracy and ranks among the top ten industrial nations._^<g_See also: _^<a!T10132_Dravidian languages_^>a_; _^<a!T22250_Moguls (dynasty)_^>a_._^<g_
The era of the _^<a!T14718_Gupta_^>a_ dynasty (AD _^<i_c._^>i_320 to _^<i_c._^>i_540) is generally thought of as ancient India's classic period. Art, literature, and science reached levels so high that they set a standard which became both the ideal and the despair of Indians in later times. Architecture, sculpture, painting, dance and music flourished. _^<a!T11775_Faxian_^>a_ (Fa-hsien), a Chinese pilgrim who visited Gupta dominions from 405 to 411, reported his impressions and left to his readers a view of the empire at its height._^<g_See also: _^<a!T16803_Indian art and architecture_^>a_; _^<a!T16800_India, history of_^>a_._^<g_
On Christmas Day, AD 800, _^<a!T6585_Charlemagne_^>a_, or Charles the Great, _^<a!T5960_Carolingian_^>a_ king of the _^<a!T12685_Franks_^>a_ (and ruler of the dynasty which bears his name), was crowned emperor of the _^<a!T16009_Holy Roman Empire_^>a_. The revival of the imperial, scholarly, and lawmaking traditions of the Roman Empire during Charlemagne's reign came to be known as the _^<i_Carolingian Renaissance_^>i_ and was among the achievements for which he is best remembered._^<g_See also: _^<a!T3_Aachen_^>a_; _^<a!T19958_Lombards_^>a_; _^<a!T28927_Saxons_^>a_._^<g_
The _^<a!T29351_Seljuks_^>a_, a group of nomadic Turkoman tribespeople from Central Asia, fought their way into western Asia in the 10th century and then founded dynasties in Persia, Mesopotamia, Syria, and Asia Minor. In the Middle East during the 11th century the Seljuks established themselves as guardians of the declining _^<a!T21_Abbasid_^>a_ caliphate. The Byzantines suffered a staggering defeat to the Seljuks on the plain of _^<a!T20962_Manzikert_^>a_ (1071), opening the way for the Turkish occupation of Anatolia._^<g_
_^<a!T32531_Timur_^>a_, or Tamerlane was wounded by an arrow early in his career and nicknamed Timur the Lame. A _^<a!T22360_Mongol_^>a_ conqueror who claimed descent from _^<a!T13409_Genghis Khan_^>a_, Timur led his Turko-Mongol armies in brilliant military campaigns against _^<a!T16799_India_^>a_, Persia, and the _^<a!T24626_Ottoman Empire_^>a_. As a military tactician, Timur struck quickly and often without plan. His cruelty went beyond that of any other Mongol khan or ruler and he was responsible for the deaths of hundreds of thousands of people. In 1405, Timur died in a vain attempt to conquer China._^<g_
_^<a!T17192_Islam_^>a_ is a major world religion. Followers, known as _^<i_Muslims_^>i_ or _^<i_Moslems_^>i_, live not only in the Middle East, where Islam is the dominant religion in all countries except Israel, but also in other parts of Asia, in Africa, Europe, and the United States._^<g_During his lifetime the Prophet _^<a!T22762_Muhammad_^>a_ (570-632) initiated this religious movement and received the divine revelations recorded in the _^<a!T18604_Koran_^>a_, the sacred book of Islam. _^<a!T88_Abraham_^>a_ is the patriarch who turned away from idolatry, who "came to his Lord with an undivided heart" (37:84). The proper relationship between human persons and their God is described by the term _^<i_Islam_^>i_._^<g_Muhammad gradually became more of a political leader and Islam, the religion, became a political entity. Expansion took place by the _^<i_jihad_^>i_ or "holy war." Islam became political and militant and, in its name, lands were invaded and peoples were conquered. Two great Islamic powers from the 15th to the 18th century were the Ottomans and the Moguls. Frontier areas for the expansion of Islam included Indonesia and West Africa._^<g_Islam teaches that God has sent messengers to all peoples and so is an inclusive religion. Modern Islam shows a renewed vitality and dynamism._^<g_See also: _^<a!T860_Allah_^>a_; _^<a!T1648_Arabs_^>a_; _^<a!T17196_Islamic art and architecture_^>a_._^<g_
The departure of the Prophet _^<a!T22762_Muhammad_^>a_ from Mecca in AD 622 is called the _^<a!T15417_hegira_^>a_ (from the Arabic _^<i_hijra_^>i_, which means "breaking off relations," "abandoning one's tribe," or "migrating"). Muhammad left Mecca for reasons which included the growing opposition to his mission, the loss of support of his clan, and a plot against his life. His arrival in Medina marks the beginning of his political power. The Islamic calendar begins on the first day (July 16, 622, by the Julian calendar) of the lunar year in which the hegira occurred._^<g_See also: _^<a!T17192_Islam_^>a_._^<g_
From AD 750 until the _^<a!T22360_Mongol_^>a_ conquest of the _^<a!T21900_Middle East_^>a_ in 1258, the Islamic empire was ruled by the _^<a!T21_Abbasids_^>a_, the longest-lived and most renowned of the Islamic dynasties. In 750 the Abbasids defeated the _^<a!T33380_Umayyads_^>a_ and transferred the capital of the _^<a!T5491_caliphate_^>a_ from Damascus to _^<a!T2498_Baghdad_^>a_, thereby shifting the empire's center from _^<a!T31631_Syria_^>a_ to _^<a!T17107_Iraq_^>a_. The Abbasids maintained standing armies, and to an ever-increasing degree they based their culture on the highly developed Persian civilization._^<g_See also: _^<a!T15472_Hellenism_^>a_._^<g_
The city of _^<a!T2498_Baghdad_^>a_ (Persian for "God-given"), which is situated on both banks of the _^<a!T32489_Tigris River_^>a_, stands at the junction of many of the great trade routes that have shaped the politics and economics of the _^<a!T21900_Middle East_^>a_. In 1055, after establishing control in Persia, the Seljuk Turks led by Tughril Beg entered Baghdad, deposed the rulers, and sacked the city, thus founding the Great Seljuk sultanate, an empire centered there which included Iran, Iraq, and Syria._^<g_See also: _^<a!T29351_Seljuks_^>a_._^<g_
The term _^<a!T34021__^<i_Vikings_^>i__^>a_ designates the adventurous people of the North (Norwegians, Swedes, and Danes) in the years between AD 800 and 1100. Northmen themselves used the name _^<i_Viking_^>i_ in the sense of "one who fares by the sea to his adventures of commerce and war." Some Vikings reached the northernmost tip of _^<a!T23548_Newfoundland_^>a_ around AD 1000; archaeologists think that their site at _^<a!T18795_L'Anse aux Meadows_^>a_ was only used for just a short time. It is not clear whether or not this was the site of _^<a!T34069_Vinland_^>a_, a discovery attributed to _^<a!T19385_Leif Eriksson_^>a_._^<g_
_^<a!T5026_Bubonic plague_^>a_-infected rats aboard a merchant ship traveling from Tana in the Crimea to Messina in Sicily brought the _^<a!T3827_Black Death_^>a_ to Europe in 1347. One-fourth to one-half the population of Europe (about 75 million people) died from this acute infection. Bubonic plague produces vomiting, muscular pain, mental disorganization, and delirium; in 60 to 90 percent of untreated cases, death occurs within a few days. The Black Death halted economic growth in Europe for two centuries._^<g_
According to tradition, _^<a!T5060_Buddhism_^>a_ was first introduced to _^<a!T17427_Japan_^>a_ about the 6th century. A mission to the emperor of Japan sent by the king of Paekche, a kingdom on the Korean peninsula, arrived with gifts, "an image of Sakyamuni Buddha, cast in gold and copper, several flags and umbrellas, and a number of Sutras (Buddhist sacred scriptures)." Buddhism received the patronage of Prince _^<a!T29775_Shotoku_^>a_ (7th century) who is considered the person most responsible for its acceptance._^<g_See also: _^<a!T17428_Japan, history of_^>a_._^<g_
The _^<a!T23095_Nara_^>a_ period in the history of _^<a!T17427_Japan_^>a_ was one of aristocratic government which would continue until well into the 12th century. Construction of a new city to be the first permanent capital was completed in 710; one writer described its palaces, government offices, temples, and residences seen against the background of pine-covered hills as "a city of cinnabar and green." Authors composed the first histories of Japan, the _^<i_Kojiki_^>i_ and the _^<i_Nihonshiki_^>i_. Buddhism, patronized by the imperial family and the court aristocracy became a major force._^<g_See also: _^<a!T17428_Japan, history of_^>a_._^<g_
_^<a!T28284_Russia_^>a_, or the Russian Federation, originated in eastern Europe and grew to become the largest country in the world. It now extends from the Baltic Sea in the west to the Pacific Ocean in the east._^<g_European Russia was occupied by _^<a!T16835_Indo-European_^>a_ and _^<a!T33529_Ural-Altaic_^>a_ peoples from about the 2d millennium BC. In the early centuries AD, a succession of tribes, the _^<a!T14088_Goths_^>a_, the _^<a!T16417_Huns_^>a_, and the _^<a!T2315_Avars_^>a_, ruled the area. The Russian people, the vast majority of the population, trace their origins to the medieval (9th-13th century) Slavic state of Kievan Rus', whose art, literature, law, and customs reflected Byzantine influence and which endured until its invasion and destruction by _^<a!T22360_Mongols_^>a_._^<g_The Russian tsar _^<a!T25540_Peter I_^>a_ (Peter the Great) began a vigorous program of Westernization in the early 18th century. During _^<a!T35394_World War I_^>a_ the Russian monarchy was overthrown and replaced by a communist government (1917). Under Joseph _^<a!T30818_Stalin_^>a_, the _^<a!T33435_Union of Soviet Socialist Republics_^>a_ underwent forced industrialization and won a costly victory over Nazi Germany in _^<a!T35397_World War II_^>a_. In December 1991 the Soviet Union was dissolved, and Russia was reborn as an independent country._^<g_In terms of natural resources Russia may well be the richest country in the world. Since the Bolshevik Revolution (1917-21), Russia has been transformed from a predominantly agrarian society to one that is chiefly urban._^<g_
One of the greatest emperors of the _^<a!T5344_Byzantine Empire_^>a_, _^<a!T17926_Justinian I_^>a_ (Justinian the Great) ruled from 527 to 565. Justinian attempted to restore the Roman Empire to its former glory. Two significant achievements of his rule were the _^<a!T17925_Justinian Code_^>a_, a revision and adaptation of Roman law to Christian needs, and the construction of the _^<a!T14824_Hagia Sophia_^>a_ (Greek for "Holy Wisdom"), a sumptuous building which was originally a Christian church, then a mosque, and is now a museum._^<g_See also: _^<a!T3239_Belisarius_^>a_; _^<a!T14088_Goths_^>a_; _^<a!T28856_Sassanians_^>a_; _^<a!T33726_Vandals_^>a_._^<g_
The first wars fought for an ideal, the _^<a!T8588_Crusades_^>a_ were a series of religious expeditions undertaken between the 11th and the 15th century to free the Holy Land from the Muslims and establish Christian rule there. The word _^<i_crusade_^>i_ is derived from the Latin _^<i_crux_^>i_ ("cross") and refers to the biblical injunction that Christians carry their cross (Matt. 10:38). Today any cooperative venture deemed worthy may be called a crusade._^<g_See also: _^<a!T7969_Constantinople, Latin Empire of_^>a_; _^<a!T16848_indulgences_^>a_; _^<a!T17545_Jerusalem, Latin Kingdom of_^>a_; _^<a!T33547_Urban II, Pope_^>a_._^<g_
Located on major caravan routes across the _^<a!T28425_Sahara_^>a_, the kingdom of Ghana was the earliest known kingdom of the _^<a!T31317_Sudan_^>a_ and the first of the great West African empires. Late in the 8th century, Arab commentators wrote that Ghana was a thriving state, ruled by Soninke kings and well-known for its wealth in gold. At the height of its power in the 10th and 11th centuries, the kingdom of Ghana ruled the area from central _^<a!T29390_Senegal_^>a_ to _^<a!T32505_Timbuktu_^>a_. After it was conquered by the _^<a!T922_Almoravids_^>a_ (_^<i_c._^>i_1076), the kingdom of Ghana continued but was no longer a major power._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T13564_Ghana, kingdom of_^>a_; _^<a!T20875_Mande_^>a_; _^<a!T34794_West Africa_^>a_._^<g_
Arab traders moved up and down the east coast of _^<a!T396_Africa_^>a_ between AD 900 and 1100. Kilwa, founded _^<i_c._^>i_1000 on what is now the Tanzanian coast, became an important trading center and controlled an ancient _^<a!T13916_gold_^>a_ route to the interior. A 13th-century Arab palace survives at Kilwa along with another ancient building which has stylistic similarities to the architecture of the Umayyad and early Abbasid caliphates of the 7th and 8th centuries AD. By the late-15th century Kilwa had become the most commercially successful trading center on the East African coast._^<g_See also: _^<a!T21_Abbasids_^>a_; _^<a!T31804_Tanzania_^>a_; _^<a!T33380_Umayyads_^>a_._^<g_
During the late-14th and early-15th centuries the highly organized Bakongo kingdom emerged around the lower course of the _^<a!T7886_Congo River_^>a_ in what is modern _^<a!T7884_Zaire_^>a_ and _^<a!T1347_Angola_^>a_. The Portuguese navigator Diogo Cam discovered the estuary of the Congo River in 1482. At least a century earlier the kingdom had been founded by Chief Nimi a Lukeni. In the 16th century, Portugal's involvement with the slave trade led to a serious deterioration of relations with the _^<a!T18591_Kongo_^>a_. The kingdom declined sharply after the reigning monarch, Antonio I, was killed in 1665._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T30103_slavery_^>a_._^<g_
The _^<a!T31774_Tang_^>a_ dynasty (r. 618-906) ruled over one of the most glorious periods in the history of _^<a!T6872_China_^>a_. Peace and prosperity (resting on internal strength and political stability) during the first half of the dynasty produced a truly remarkable cosmopolitanism. Commerce with the non-Chinese world expanded greatly. One of the notable personalities of the age was the Empress Wu (r. 690-704), the only woman to rule China in her own name. Religions in China came to include _^<a!T5060_Buddhism_^>a_, _^<a!T17192_Islam_^>a_, _^<a!T20902_Manichaeism_^>a_, _^<a!T35903_Zoroastrianism_^>a_, _^<a!T17845_Judaism_^>a_, and Nestorian Christianity. Chinese lyric poetry reached a high point; the world's first printed book was produced, and fiction first appeared in the short story form._^<g_See also: _^<a!T6885_Chinese art and architecture_^>a_; _^<a!T23405_Nestorian church_^>a_._^<g_
_^<a!T31776_Tang Xuanzong_^>a_, also known as Ming Huang (Enlightened or Lustrous Emperor), 6th emperor (r. 712-56) of the _^<a!T31774_Tang_^>a_ dynasty, presided over the second great Tang reign and an era of splendid cultural advance in _^<a!T6872_China_^>a_. During his reign, changes in the way land was taxed reflected the government's lessened control over land ownership._^<g_See also: _^<a!T6873_China, history of_^>a_; _^<a!T6885_Chinese art and architecture_^>a_._^<g_
The _^<a!T30416_Song_^>a_ (Sung) dynasty (960-1279) of _^<a!T6872_China_^>a_ reigned during a period of unusually rapid cultural achievement. Paper money was invented, and an increase in economic productivity resulted from a commercial and agricultural revolution based on technological developments. The Song period was one of the high points in Chinese intellectual and artistic history._^<g_See also: _^<a!T34411_Wang Anshi_^>a_; _^<a!T6885_Chinese art and architecture_^>a_; _^<a!T21834_Mi Fei_^>a_; _^<a!T20365_Ma Yuan_^>a_; _^<a!T35510_Xia Gui_^>a_; _^<a!T35846_Zhu Xi_^>a_._^<g_
The _^<a!T22058_Ming_^>a_ dynasty of _^<a!T6872_China_^>a_ (r. 1368-1644) was founded by Zhu Yuanzhang (r. 1368-98), an energetic and clever commoner who led a peasant army to victory over the _^<a!T22360_Mongols_^>a_. Since the founder usually sets the tone for an entire dynasty, the autocracy of the Ming emperors may be seen as due to his influence. Zhu Yuanzhang was known from his reign title as the Hung Wu ("Vast Military Power") emperor. A high point in Chinese ceramics was reached in the painted porcelain of the Ming period._^<g_See also: _^<a!T6885_Chinese art and architecture_^>a_; _^<a!T26390_pottery and porcelain_^>a_._^<g_
The Mongol leader _^<a!T13409_Genghis Khan_^>a_ ("universal ruler") conquered and led an empire that stretched from eastern Europe to the Sea of Japan. Genghis Khan's personal qualities of organization, self-discipline, ruthlessness, and cunning made him a military genius and enabled him both to unite hostile nomadic tribes and to bring order out of chaos._^<g_See also: _^<a!T1995_Asia, history of_^>a_; _^<a!T31175_strategy and tactics, military_^>a_. _^<g_
The _^<a!T815_Alhambra_^>a_ is a Moorish fortress palace in Granada, Spain whose name is derived from the Arabic _^<i_Kalat-Alhamra_^>i_, meaning "red castle." Notable features of the Alhambra include: its luxurious gardens, its fountains, a wealth of decoration, and the magical play of sunlight and shadow among the Moorish arches and pillars. Early in the 16th century, the Alhambra fell into ruin, but later it was extensively restored._^<g_See also: _^<a!T22505_Moorish art and architecture_^>a_. _^<g_
Prince _^<a!T15550_Henry the Navigator_^>a_, son of King John I of _^<a!T26336_Portugal_^>a_, became the leading promoter of _^<a!T11533_exploration_^>a_ and geographical study during the 15th century. His navigators mapped the West African coast as far as present-day _^<a!T29845_Sierra Leone_^>a_, improved the compass, and developed the three-masted _^<a!T5823_caravel_^>a_. _^<g_See also: _^<a!T13436_geography_^>a_; _^<a!T23274_navigation_^>a_; _^<a!T30103_slavery_^>a_; _^<a!T34794_West Africa_^>a_._^<g_
The term _^<a!T27500_Renaissance_^>a_ describes the fundamental changes in 15th- and 16th-century European culture and vision which transformed traditional patterns of thought and action. During this time of "rebirth," the _^<a!T21898_Middle Ages_^>a_ came to an end and the values of the modern world began to emerge. Confidence in human potential in general and the idea of the artist as a genius who takes pride in individual creativity are two ideas which clearly indicate the Renaissance mentality._^<g_See also: _^<a!T19458_Leonardo da Vinci_^>a_; _^<a!T21855_Michelangelo_^>a_; _^<a!T27501_Renaissance art and architecture_^>a_._^<g_
On October 12, 1492 the Spanish fleet of Christopher _^<a!T7682_Columbus_^>a_ made landfall on one of the _^<a!T2506_Bahama Islands_^>a_, and discovered the New World, _^<a!T1031_America_^>a_. Columbus named the island San Salvador (it was called "Guanahani" by the native _^<a!T1671_Arawak_^>a_ Indians). The achievement of this Italian-born navigator differs in its results from the adventures of British or Norse sailors who may have reached the land now called America much earlier. The earlier landings were without significant result; the consequences of Columbus' discovery included rapid, widespread, and permanent settlement._^<g_See also: _^<a!T11533_exploration_^>a_; _^<a!T23274_navigation_^>a_._^<g_
One of the Turkmen principalities in northeastern Anatolia, that of the Ottomans, built a new empire starting in the 14th century. Using an army of Oghuz nomads and Christian mercenaries, the Ottomans conquered southeastern Europe as far as the Danube in the 15th century. The fall of _^<a!T7969_Constantinople_^>a_ to the Ottoman sultan _^<a!T21533_Mehmed II_^>a_ in 1453 marked the end of the Byzantine state. The Ottomans went on to overrun Egypt, Syria, and Arabia._^<g_See also: _^<a!T17238_Istanbul_^>a_; _^<a!T24626_Ottoman Empire_^>a_; _^<a!T33201_Turks_^>a_._^<g_
The _^<a!T16773_Incas_^>a_ ruled the largest native empire in the Americas. Despite limited _^<a!T32878_transportation_^>a_ (the Incas had neither the _^<a!T34855_wheel_^>a_ nor the _^<a!T16167_horse_^>a_) and communication, remarkable territorial expansion began under _^<a!T24723_Pachacuti_^>a_ (r. 1438-1471). The Incas ran a prosperous organized society with a state-run economy and showed great engineering skill in what they managed to do with their forbidding landscape of desert coast, broad rivers, and the gorges and ravines of the _^<a!T1275_Andes_^>a_. In 1532 the Spanish conquistador Francisco _^<a!T25941_Pizarro_^>a_, with about 150 soldiers, took the Inca ruler captive and assured the collapse of the empire._^<g_See also: _^<a!T7927_conquistadors_^>a_; _^<a!T25513_Peru_^>a_._^<g_
In the Valley of _^<a!T21816_Mexico_^>a_, Tenochtitlan had become an independent _^<a!T2393_Aztec_^>a_ state in alliance with the neighboring cities of Texcoco and Tlacopan by 1431. This triple alliance then began a program of military expansion. Montezuma I (r. 1440-1469), grandfather of _^<a!T22446_Montezuma II_^>a_, expanded the Aztec empire from the Atlantic to the Pacific. A total of 489 cities paid tribute to the alliance._^<g_See also: _^<a!T21817_Mexico, history of_^>a_._^<g_
At the Council of Florence in 1439, the Byzantine emperor attempted to heal the rift or "Great Schism" between the Eastern and the Roman Churches by uniting the _^<a!T24545_Orthodox church_^>a_ and the Catholic Church. The Muscovites (after "Muscovy," one of the names for Russia at that time) opposed this union. After the fall of Constantinople in 1453, _^<a!T22637_Moscow_^>a_ and its Church were the only representatives of Orthodoxy who remained independent. In 1472, _^<a!T17263_Ivan III_^>a_ married a niece of Constantine XI, the last Byzantine emperor and proclaimed _^<a!T28284_Russia_^>a_, protector of the Orthodox Church._^<g_See also: _^<a!T11893_Ferrara-Florence, Council of_^>a_; _^<a!T27984_Roman Catholic church_^>a_; _^<a!T28285_Russia, history of_^>a__^<g_
_^<a!T17263_Ivan III, Grand Duke of Moscow_^>a_ from 1462 to 1505, became known as Ivan the Great, and was the first Muscovite ruler to call himself "Grand Prince of all Russia." Ivan set out to unify and centralize Russian lands. With the help of Italian architects, he converted the administrative center of the Moscow _^<a!T18676_Kremlin_^>a_ into a symbol of his power and largely gave it the shape it has today. After 1472, Ivan began to use the title _^<i_tsar_^>i_ (a variation of the word _^<i_caesar_^>i_)._^<g_See also: _^<a!T28285_Russia, history of_^>a_; _^<a!T28288_Russian art and architecture_^>a_._^<g_
In 1453 the Ottoman sultan _^<a!T21533_Mehmed II_^>a_, known as _^<i_Fatih_^>i_ ("the Conqueror"), took Constantinople, thus bringing an end to the _^<a!T5344_Byzantine Empire_^>a_. He established Constantinople as the capital of the _^<a!T24626_Ottoman Empire_^>a_, making the city as significant for Islam as it had been for Christianity. Situated at the junction of two continents, today _^<a!T17238_Istanbul_^>a_ (as Constantinople was officially renamed in 1930) remains preeminent in Turkish industry, commerce, and culture._^<g_See also: _^<a!T10480_Early Christian art and architecture_^>a_; _^<a!T33189_Turkey_^>a_; _^<a!T33201_Turks_^>a_._^<g_
Civil conflict in 15th-century England between the houses of _^<a!T18979_Lancaster_^>a_ and _^<a!T35659_York_^>a_, each of which made a claim to the English crown, became known as the Wars of the Roses (1455-1485). History is not clear about the name, first used long after the wars took place; allegedly it refers to the white rose of York and the red rose of Lancaster. After the final battle at Bosworth Field (1485), the Lancastrian claimant, Henry Tudor, was crowned _^<a!T15560_Henry VII_^>a_._^<g_See also: _^<a!T14297_Great Britain, history of_^>a_; _^<a!T28076_Roses, Wars of the_^>a_; _^<a!T33126_Tudor (dynasty)_^>a_._^<g_
From among the Nubians, ancient residents of the Nile Valley and builders of a civilization in the _^<a!T31317_Sudan_^>a_, came the Bechwezi, a people who moved south to set up a powerful kingdom _^<i_c._^>i_AD 1350 between Lake Victoria and Lake Mobutu (Lake Albert) in what is now _^<a!T33345_Uganda_^>a_. With reeds and grasses, the Bechwezi built splendid palaces and shrines in this lake area of _^<a!T10505_East Africa_^>a_. Notable Bechwezi rulers were Ndahura and Wamara. Their decline began with the coming of the _^<a!T20266_Luo_^>a_, _^<i_c._^>i_1500._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T23950_Nubia_^>a_._^<g_
The tragedy of the 400-year maritime slave trade began _^<i_c._^>i_1450, when the Portuguese began shipping slaves from _^<a!T34794_West Africa_^>a_. _^<a!T30103_Slavery_^>a_ is a condition in which one person owns another and controls his or her life. Trade in and transport of slaves to the New World did not become substantial until the 17th century, when a great need for labor arose in the cotton, sugar, and tobacco plantations. From the 16th through the 19th century, the dreaded "Middle Passage" in overcrowded slave ships brought an estimated eight to fifteen million Africans to the Americas._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T26337_Portugal, history of_^>a_._^<g_
_^<a!T17605_Joan of Arc_^>a_ was burned at the stake in Rouen, France, for _^<a!T35226_witchcraft_^>a_ and _^<a!T15619_heresy_^>a_ in 1431. An illiterate peasant girl, she had restored the morale of the French in their struggle against the English during the _^<a!T16408_Hundred Years' War_^>a_. Called the Maid of Orleans, Joan of Arc, a French national heroine and patron _^<a!T28437_saint_^>a_, has been the subject of much art and literature. Many French cities and towns have monuments to her memory._^<g_See also: _^<a!T12625_France, history of_^>a_._^<g_
Anything communicated in writing before the invention of _^<a!T26581_printing_^>a_ was done one copy at a time. In medieval paintings, monks with quill pens laboriously copied sacred texts. Since there were not many copies of any books that existed at the time, very few people had access to them. This all changed when, in 1455, Johann _^<a!T14733_Gutenberg_^>a_ worked out a method of casting type and printing so successful that its fundamental principles were not improved upon until well into the 19th century. The effects of Gutenberg's invention on literacy and on the availability of reading materials were nothing short of revolutionary._^<g_See also: _^<a!T14734_Gutenberg Bible_^>a_; _^<a!T19816_literacy and illiteracy_^>a_; _^<a!T24925_paper_^>a_; _^<a!T33301_type and typesetting_^>a_._^<g_
_^<a!T21396_Maximilian I_^>a_, the Habsburg archduke of _^<a!T2277_Austria_^>a_ who became Holy Roman Emperor in 1493 and ruled until 1519, expanded _^<a!T14789_Habsburg_^>a_ interests by negotiating complex dynastic marriage contracts. His attempts to centralize the judiciary, the army, and the finances of the empire did not completely succeed since they were perceived by some as further efforts to strengthen the Habsburgs. One of the most colorful of the Habsburg rulers, Maximilian was often given to grandiose fantasies._^<g_See also: _^<a!T12624_France_^>a_; _^<a!T16009_Holy Roman Empire_^>a_; _^<a!T33672_Valois, dynasty_^>a_._^<g_
The _^<a!T13996_gong_^>a_ is a circular precision musical instrument of the percussion family which produces a deep, reverberating tone. Usually at least three feet in diameter, the gong may be tuned or of indefinite _^<a!T25912_pitch_^>a_; it is played by being struck with a padded hammer or mallet. The gong is thought to have originated in _^<a!T6872_China_^>a_, where it was known by the 6th century AD._^<g_See also: _^<a!T22927_musical instruments_^>a_._^<g_
_^<a!T10915_Ellora_^>a_, one of the architectural wonders of _^<a!T16799_India_^>a_, is a site in _^<a!T20693_Maharashtra_^>a_ state containing 34 rock-cut temples built from the mid-fourth to the late-ninth century AD. The 12 oldest are Buddhist, 17 are Hindu, and the 5 newest are Jain. The most remarkable _^<a!T32059_temple_^>a_ is the Kailasa, a Hindu shrine built in the 8th century and dedicated to _^<a!T29736_Shiva_^>a_; it is painted white to stress its symbolic relationship to Shiva's eternal home, the snowcapped peaks of the _^<a!T15808_Himalayas_^>a_._^<g_See also: _^<a!T5060_Buddhism_^>a_; _^<a!T15818_Hinduism_^>a_; _^<a!T16803_Indian art and architecture_^>a_; _^<a!T17372_Jainism_^>a_._^<g_
The _^<a!T12416_Forbidden City_^>a_ refers to the still-moated and walled precinct of Imperial Palace buildings (built from 1407 to 1421 and used by Chinese emperors between 1421 and 1911) found within the former Imperial City of _^<a!T3202_Beijing_^>a_ (Peking), _^<a!T6872_China_^>a_. The walls are up to 11 m (35 ft) high and are faced with purplish glazed bricks. In the city, there are palaces, shrines, halls, marble terraces and bridges, buildings with gleaming yellow-tiled roofs, and formal gardens. The Forbidden City has been open to the public as a museum since 1949._^<g_See also: _^<a!T6873_China, history of_^>a__^<g_
Ferdinand _^<a!T20637_Magellan_^>a_, whose westward voyage to the Spice Islands became the first circumnavigation of the globe (1519-1522), set out from Seville, _^<a!T30557_Spain_^>a_ on September 20, 1519, on what proved to be a grueling three-year expedition. Although he was killed in the Philippines before the journey's end, Magellan is credited with inspiring and commanding a journey that dramatically altered the geographical knowledge of his day._^<g_See also: _^<a!T11533_exploration_^>a_; _^<a!T13436_geography_^>a_; _^<a!T22314_Moluccas_^>a_._^<g_
Jacques _^<a!T6037_Cartier_^>a_ explored the St. Lawrence River as far inland as present-day _^<a!T22464_Montreal_^>a_ and established France's claim to _^<a!T5637_Canada_^>a_. The narratives which Cartier wrote describing his three voyages to _^<a!T23840_North America_^>a_ (1534-42) were variously published in French, English, and Italian between 1545 and 1600 and served to stimulate later voyages of discovery. Originally Cartier intended to search for the _^<a!T23887_Northwest Passage_^>a_ to the Orient._^<g_See also: _^<a!T5639_Canada, history of_^>a_; _^<a!T11533_exploration_^>a_._^<g_
The conqueror of _^<a!T16773_Inca_^>a_ Peru, Francisco _^<a!T25941_Pizarro_^>a_, destroyed the weakened empire of _^<a!T2094_Atahualpa_^>a_ when his well-equipped but outnumbered troops took Cajamarca in 1533. This was part of what has come to be called the "Spanish Conquest" when, between 1519 and 1542, _^<a!T30557_Spain_^>a_ conquered the _^<a!T21406_Maya_^>a_, the Aztecs, and the Incas. The Maya of Yucatan, wracked by strife and then by European diseases, had broken up into 16 tiny, warring states which the Spanish gradually took control of between 1528 and 1542. Through political and strategic skill, Hernan _^<a!T8214_Cortes_^>a_, a Spanish _^<a!T7927_conquistador_^>a_, successfully invaded and colonized _^<a!T21816_Mexico_^>a_, and defeated the _^<a!T2393_Aztec_^>a_ Empire by 1521._^<g_
The far-reaching effects of the defeat of the _^<a!T30564_Spanish Armada_^>a_ in 1588 included breaking the Spanish-Portuguese monopoly of overseas empire and opening the way for colonial expansion by _^<a!T11035_England_^>a_, _^<a!T12624_France_^>a_, and Holland. A great Spanish fleet of 130 ships carrying a crack _^<a!T16873_infantry_^>a_ had been assembled by _^<a!T25657_Philip II_^>a_, whose intent was to invade England and confront the bold and colorful "Sea Dogs," led by John Hawkins and Sir Francis _^<a!T10118_Drake_^>a_. The English use of new long-range naval tactics was one of the reasons for the Spanish defeat._^<g_See also: _^<a!T7636_colonialism_^>a_; _^<a!T12625_France, history of_^>a_; _^<a!T20140_Low Countries, history of_^>a_; _^<a!T23278_navy_^>a_; _^<a!T23410_Netherlands_^>a_._^<g_
_^<a!T17264_Ivan IV_^>a_, known as "the Terrible," was the first Russian ruler to be officially crowned with the title of _^<i_tsar_^>i_. Ruling between 1533 and 1584, he made _^<a!T28284_Russia_^>a_ a major power in eastern Europe. Two _^<a!T31885_Tatar_^>a_ states were annexed: _^<a!T18135_Kazan_^>a_ (1552) and _^<a!T2067_Astrakhan_^>a_ (1556), the first non-Slavic states in the empire. Trade contacts with the English, French, and Dutch were begun. However, from 1558 Ivan overextended the state's resources and brought Russia to defeat and economic collapse._^<g_See also: _^<a!T28285_Russia, history of_^>a__^<g_
During the first _^<a!T32511_Time of Troubles_^>a_ in Russian history the edicts of Fyodor I (r. 1584-98) and _^<a!T4314_Boris Godunov_^>a_ (r. 1598-1605) initiated a process that culminated in the complete enserfment (or virtual enslavement) of the Russian peasantry. A serf was a member of a servile feudal class bound to the soil and subject to the will of his master. Many consider that serfdom fully arrived for the landlords' peasants when a new legal code, the _^<i_ulozheniye_^>i_, was adopted in 1649. Serfs were not emancipated until 1861 in _^<a!T28284_Russia_^>a_, where the last elements of the manorial system remained until the Revolution of 1917._^<g_See also: _^<a!T11930_feudalism_^>a_; _^<a!T20931_manorialism_^>a_; _^<a!T25230_peasant_^>a_; _^<a!T28285_Russia, history of_^>a_._^<g_
The Italian _^<a!T21855_Michelangelo_^>a_ Buonarotti, universally considered the supreme _^<a!T27500_Renaissance_^>a_ artist, frescoed the ceiling of the _^<a!T30021_Sistine Chapel_^>a_ in the years between 1508 and 1512 with perhaps the most complex composition in Western art; this work, beginning with creation, is a pictorial cycle devoted to Biblical history. The Sistine Chapel is a 15th-century papal chapel in the Vatican where the elections of popes are traditionally held. A recent project to clean the frescoes and reveal the original colors was completed in 1990._^<g_See also: _^<a!T24914_papacy_^>a_; _^<a!T27501_Renaissance art and architecture_^>a_._^<g_
On October 31, 1517, Martin _^<a!T20288_Luther_^>a_, an Augustinian monk and German theologian who hoped to kindle reform within the Roman Catholic Church, posted his 95 theses--95 paragraphs for discussion--on the door of the castle church at Wittenberg. Although some of his theses directly criticized papal policies, Luther had put them forward as tentative topics for discussion. Copies of the 95 theses, spread throughout Europe, unleashed a storm of controversy and catalyzed the events of the movement which came to be known as the _^<a!T27420_Reformation_^>a_._^<g_See also: _^<a!T16848_indulgences_^>a_; _^<a!T26686_Protestantism_^>a_; _^<a!T27984_Roman Catholic church_^>a_._^<g_
French theologian John _^<a!T5530_Calvin_^>a_ became one of the public leaders of the Protestant _^<a!T27420_Reformation_^>a_ as he lived and worked in Geneva, Switzerland. In the _^<i_Institutes of the Christian Religion_^>i_ (1536-39) Calvin wrote a comprehensive _^<a!T32250_theology_^>a_ which presents a vision of _^<a!T13869_God_^>a_ in his majesty; of _^<a!T6995_Christ_^>a_ as _^<a!T26664_prophet_^>a_, _^<a!T26541_priest_^>a_, and _^<a!T18383_king_^>a_; of the _^<a!T16010_Holy Spirit_^>a_ as the giver of faith; the _^<a!T3610_Bible_^>a_ as the final authority; and the _^<a!T7075_church_^>a_ as the holy people of God. According to Calvin, we are called to serve God and "to serve our neighbor with good conscience."_^<g_See also: _^<a!T22069_ministry, Christian_^>a_; _^<a!T26471_predestination_^>a_; _^<a!T27480_religion_^>a__^<g_
The _^<a!T16933_Inquisition_^>a_, formally instituted by Pope Gregory IX in 1231, was a tribunal established by the Catholic Church in the Middle Ages with very wide powers for the suppression of heresy. The name _^<i_Inquisition_^>i_ was derived from the Latin _^<i_inquirere_^>i_, "to inquire." At the time of the _^<a!T27420_Reformation_^>a_ in 1542, Pope Paul III created a cardinals' commission at the curia as the final court of appeal in matters of heresy. The procedure was to search out heretics and other offenders instead of waiting for charges to be made. When found, heretics were subjected to intense interrogations which might lead to social ostracism, physical torture, imprisonment, or death. The Inquisition, generally acknowledged to belong to the darker side of Christian history, can only be seriously studied within the context of the society that produced it._^<g_See also: _^<a!T3610_Bible_^>a_; _^<a!T8296_Counter-Reformation_^>a_; _^<a!T15619_heresy_^>a_; _^<a!T21898_Middle Ages_^>a_; _^<a!T27984_Roman Catholic church_^>a_._^<g_
The _^<a!T32935_Council of Trent_^>a_, the 19th _^<a!T8288_ecumenical council_^>a_ of the _^<a!T27984_Roman Catholic church_^>a_, took place at Trent in northern Italy between 1545 and 1563. The two aims of the council were: to state Catholic doctrine in view of the Protestant positions; and, to institute the reforms needed within the Roman Catholic Church itself. It achieved a high degree of success on both scores and has ranked ever since as one of the most important councils in the history of Catholicism._^<g_See also: _^<a!T8296_Counter-Reformation_^>a_; _^<a!T27420_Reformation_^>a_._^<g_
Throughout 16th-century Europe, _^<a!T17572_Jews_^>a_ continually suffered persecutions and expulsion, usually at the hands of Christians. In 1516 a walled enclosure was established in _^<a!T33844_Venice_^>a_, the _^<a!T13573_ghetto_^>a_, where Jews were kept apart from non-Jews. Locked in at night and on Christian holidays, Jews were forced to wear a distinguishing badge whenever they went outside the walls. The word _^<i_ghetto_^>i_, originally from a Venetian dialect, came to mean the quarter of a city in which members of any minority group live because of social, legal, or economic pressure._^<g_See also: _^<a!T1513_anti-Semitism_^>a__^<g_
The enunciation of the heliocentric theory by _^<a!T8086_Copernicus_^>a_, a Polish astronomer, marked the beginning of the scientific revolution and a new view of a greatly enlarged universe. Copernicus suggested that the _^<a!T31393_Sun_^>a_ is the center of the universe and that the planets, including the _^<a!T10483_Earth_^>a_, revolve around it. This was a shift away from the comfortable anthropocentrism of the ancient and medieval world. Copernicus is considered the founder of modern astronomy. An undocumented but often repeated story holds that he received a printed copy of his treatise on his deathbed. He died on May 24, 1543._^<g_See also: _^<a!T15459_heliocentric world system_^>a_; _^<a!T25967_planets and planetary system_^>a_._^<g_
Gerardus _^<a!T21658_Mercator_^>a_, a Flemish geographer and mapmaker, projected the meridians and latitudes of the globe onto a cylinder that was tangent to the Earth at the equator, and first used this cylindrical projection on his world map of 1569. Only four copies of this map are still known to exist. The Mercator map projection was very important for 16th-century _^<a!T11533_exploration_^>a_ and is still used by navigators._^<g_See also: _^<a!T12185_Flanders_^>a_._^<g_
The English dramatist and poet William _^<a!T29561_Shakespeare_^>a_ (1564-1616) is generally considered to be the greatest author in any language, ancient or modern. 36 plays, 154 sonnets, and two narrative poems make up the body of his work. His language has profoundly affected everyday English. His insight into essential human character seems to transcend all times and fashions, and his appeal extends to all cultures; for example, _^<i_Macbeth_^>i_ is a success in Bantu languages. The poet John _^<a!T10211_Dryden_^>a_ said that Shakespeare, "of all modern, and perhaps ancient poets, had the largest and most comprehensive soul."_^<g_See also: _^<a!T10123_drama_^>a_; _^<a!T13806_Globe Theater_^>a_; _^<a!T26087_poetry_^>a_; _^<a!T30427_sonnet_^>a_; _^<a!T30429_Sonnets of Shakespeare_^>a_. _^<g_
As the 15th century drew to a close, the Portuguese navigator Vasco da Gama led an expedition that opened the sea route to _^<a!T16799_India_^>a_ by way of the Cape of Good Hope. The route he established was to be followed throughout the days of sail. The expedition crossed the Indian Ocean in 23 days, aided by the Indian pilot Ibn Majid, and, on May 20, 1498, three small ships dropped anchor off Calicut on India's Malabar coast. Although Da Gama was unable to conclude a treaty or commercial agreement in Calicut, he was able to verify the prospect of immense profits there._^<g_See also: _^<a!T11533_exploration_^>a_; _^<a!T13143_Gama, Vasco da_^>a_; _^<a!T16800_India, history of_^>a_._^<g_
The first ruler of the _^<a!T22250_Mogul_^>a_ dynasty (r.1526-1857) was _^<a!T2432_Babur_^>a_ (r.1526-30), who claimed descent on his father's side from _^<a!T32531_Timur_^>a_ and on his mother's side from _^<a!T13409_Genghis Khan_^>a_. He laid a foundation for the Mogul empire (the most glorious in _^<a!T16799_India_^>a_'s history), which was later to be consolidated by his grandson, _^<a!T576_Akbar_^>a_. Babur, a highly cultured man, ordered a new capital built at Agra and brought architects from Persia to design it. His writings tell of Hindu customs and social institutions and of Indian flora and fauna. He was a poet and the author of memoirs (Eng. trans., 1921-22). The name _^<i_Babur_^>i_ (meaning "tiger") is also transliterated as Baber or Babar._^<g_See also: _^<a!T16800_India, history of_^>a__^<g_
One of the 16th century's most remarkable personalities and the greatest of the _^<a!T22250_Mogul_^>a_ emperors was _^<a!T576_Akbar_^>a_ (r. 1556-1605), who built an administrative machinery that endured in _^<a!T16799_India_^>a_. Akbar displayed religious tolerance and assembled representatives of different religions at his court. After listening to their discourses, Akbar promulgated a new religion, the _^<i_Din-i-ILahi_^>i_ (Divine Faith), a blend of _^<a!T17192_Islam_^>a_, _^<a!T15818_Hinduism_^>a_, and other traditions. The benefits to India from the reign of Akbar include the development of trade, and the establishment of both a fair tax system and a uniform system of weights and measures._^<g_See also: _^<a!T16800_India, history of_^>a_; _^<a!T16803_Indian art and architecture_^>a_._^<g_
Human beings' persistent curiosity has spawned great finds and wonderful achievements. Explorers in the 15th century found a "New World." The age of European discovery began in a Portuguese port in 1415 and persisted until the western frontier of North America was settled in the late-19th century. In 1492 Christopher _^<a!T7682_Columbus_^>a_, searching for a westward sea route to India, landed in the _^<a!T2506_Bahama Islands_^>a_ and discovered America. Between 1519 and 1522, Ferdinand _^<a!T20637_Magellan_^>a_'s expedition went all the way around the world for the first time. Vasco da _^<a!T13143_Gama_^>a_ reached Calicut, India in 1498._^<g_The settlement and empire-building which followed these discoveries tested endurance, ingenuity, and perseverance, and sometimes generated hostile clashes of ideas and cultures between native populations and Europeans. Europe, too, was changed in many ways by this process: its view of the world would never be the same; tomatoes, potatoes, and corn were introduced from the New World; the way to _^<a!T16799_India_^>a_ had been made clear._^<g_
Tourists are often drawn to _^<a!T28442_Saint Augustine_^>a_, Florida, the oldest city in the United States, for its historical importance and its mild climate. Juan _^<a!T26230_Ponce de Leon_^>a_ had arrived in 1513 in search of the Fountain of Youth and claimed the area for _^<a!T30557_Spain_^>a_. Saint Augustine was founded in 1565 by Pedro _^<a!T21616_Menendez de Aviles_^>a_, who established the Spanish colony of _^<a!T12265_Florida_^>a_. The city is in northeastern Florida, 8 km (5 mi) from the Atlantic Ocean on Matanzas Bay._^<g_See also: _^<a!T11533_exploration_^>a_._^<g_
_^<a!T27837_Roanoke Colony_^>a_ (in present-day _^<a!T23848_North Carolina_^>a_), the first English colonizing venture in the New World, was organized by Sir Walter _^<a!T27179_Raleigh_^>a_, a colonizer, courtier, and writer, and a favorite of _^<a!T10888_Elizabeth I_^>a_. In 1585-86 a group led by Raleigh's cousin, Sir Richard _^<a!T14438_Grenville_^>a_, built a fort and attempted settlement. A year later, Raleigh dispatched three ships and 117 people to Roanoke. Their leader, John White, sailed back to England for supplies, but when he returned in 1590 the settlers had vanished without a trace. The fate of what came to be known as the "Lost Colony" remains a mystery. Among the settlers who vanished was the first child born of English parents in America, Virginia _^<a!T8968_Dare_^>a_. _^<g_See also: _^<a!T11533_exploration_^>a_; _^<a!T34095_Virginia_^>a__^<g_
Under _^<a!T31352_Suleiman I_^>a_ the Ottoman _^<a!T33201_Turks_^>a_ unsuccessfully besieged the city of _^<a!T33999_Vienna_^>a_ in 1529; this effectively stopped their attempt to overrun Europe at the _^<a!T8951_Danube River_^>a_. Another unsuccessful Turkish siege of Vienna took place in 1683. Originally a Celtic settlement, the town called _^<i_Vindobona_^>i_ served as a garrison under the Romans. For several centuries the capital of the _^<a!T14789_Habsburg_^>a_ dynasty (Holy Roman emperors and, later, emperors of Austria) and an economic hub, Vienna today retains its sophistication, rich culture, and joie de vivre._^<g_See also: _^<a!T17659_John I, King of Hungary_^>a_; _^<a!T24626_Ottoman Empire_^>a_._^<g_
The apogee of power and glory of the _^<a!T24626_Ottoman Empire_^>a_ was reached during the reign of its 10th ruler, _^<a!T31352_Suleiman I_^>a_ (r. 1520-66), known as Suleiman the Magnificent. Suleiman, called the "Lawgiver," provided each province in his empire with an individual statute of obligations and privileges, and his military conquests created a wealth which made possible a cultural flowering of art, architecture, and literature._^<g_See also: _^<a!T21901_Middle East, history of_^>a_._^<g_
_^<a!T20_Abbas I_^>a_, who came to be known as Abbas the Great, was shah of Persia from 1588 to 1629. An administrative genius, Abbas I brought security and order out of anarchy, oversaw expansion of the public works infrastructure, introduced necessary laws, and encouraged commerce. He was a superb military strategist who expanded Persia's boundaries from the _^<a!T16850_Indus_^>a_ in the east to the _^<a!T32489_Tigris_^>a_ in the west. He made his new capital at _^<a!T17182_Isfahan_^>a_ a magnificent, world-famous cultural center. A member of the Safavid dynasty, Abbas I is regarded as one of the greatest Persian rulers._^<g_See also: _^<a!T28401_Safavids_^>a_; _^<a!T33606_Uzbek_^>a_._^<g_
The _^<a!T27420_Reformation_^>a_ (1517-1648) was a religious, social, and political controversy over the proper interpretation of the Christian faith. Its name comes from the Latin _^<i_reformare_^>i_, which means "to renew." This controversy stemmed from great misunderstandings on both sides and led to a breach between the _^<a!T27984_Roman Catholic church_^>a_ and the reformers whose beliefs and practices came to be called _^<a!T26686_Protestantism_^>a_._^<g_The Reformation began when Martin _^<a!T20288_Luther_^>a_, an Augustinian monk, posted _^<i_95 Theses_^>i_ inviting debate over the legitimacy of the sale of _^<a!T16848_indulgences_^>a_ on the door of a church in Wittenberg, Germany._^<g_Religious debates and bloody religious wars followed. The debates explored the theological dispute about the proper understanding of the Christian religion. In many places, the political controversy about the legal status of the new Reformation churches erupted into war. The _^<a!T34835_Peace of Westphalia_^>a_ (1648), which ended the _^<a!T32315_Thirty Years' War_^>a_, marked the end of the Reformation._^<g_See also: _^<a!T3610_Bible_^>a_; _^<a!T8296_Counter-Reformation_^>a_._^<g_
The year 1543 marked the end of the reign of Alfonso I, _^<i_mani-kongo_^>i_ (the title for a monarch) of the Kingdom of the _^<a!T18591_Kongo_^>a_. Nzinga Mbemba (the African name of Alfonso I) was the first of the Kongo rulers converted to Christianity who adopted Portuguese reign names. Alfonso would later regret the steps he took to open his country to the slave trade._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T7882_Congo_^>a_; _^<a!T26337_Portugal, history of_^>a_; _^<a!T30103_slavery_^>a__^<g_
Between 1490 and 1500, groups of _^<a!T20266_Luo_^>a_ arriving from the north established the kingdom of Bunyoro in the _^<a!T2719_Bantu_^>a_ area of the Great Lakes in East Africa. The Luo set up a ring of tributary states around Bunyoro--Buddu, Buganda, Buruli, the Busoga principalities, and others. Under the seminomadic Bito kings, who are remembered to have ruled for eighteen generations, Bunyoro reached its height. Some leaders of modern _^<a!T18236_Kenya_^>a_ claim a Luo heritage._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T13166_Ganda_^>a_; _^<a!T33345_Uganda_^>a__^<g_
Mai Idris Alooma, the greatest of the kings of _^<a!T18017_Kanem-Bornu_^>a_, ruled this central Saharan kingdom at the height of its power. His reign was contemporary with that of _^<a!T10888_Elizabeth I_^>a_ in England. Chronicles kept of Idris Alooma's reign by his chief imam, Ahmad ibn Fartua, noted that the mai was "an accomplished diplomat and was conversant with correct procedure and methods of negotiation." Idris Alooma united the grassland county from _^<a!T8970_Darfur_^>a_ in the east to the kingdoms of eastern Hausaland. He died in 1617. Today modern _^<a!T23652_Nigeria_^>a_, _^<a!T23648_Niger_^>a_, _^<a!T6424_Chad_^>a_, and _^<a!T5574_Cameroon_^>a_ lie within the ancient kingdom of Kanem-Bornu._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T15248_Hausa_^>a_; _^<a!T18045_Kanuri_^>a_; _^<a!T34794_West Africa_^>a_. _^<g_
The Monomotapa empire in _^<a!T35855_Zimbabwe_^>a_, one of the most successful of the interior kingdoms in _^<a!T396_Africa_^>a_, grew from a set of chiefdoms into a very large state. Its first ruler, King Mutota, who rose to power in 1440, had led a campaign of military unification and was given the honorary title _^<i_Monomotapa_^>i_ ("lord of the plundered lands"), which became the name of the empire. The empire's resources, including _^<a!T13916_gold_^>a_, coral, copper, ivory, amber and pearls, became items of trade. One Portuguese trader who visited in 1518, Duarte Barbosa, reported that the Monomotapa ruler was "a great lord, with many kings under him." Although the wealthy kingdom fell under Portuguese control in 1629, reports dated c.1800 place much of modern Zimbabwe within the Monomotapa empire._^<g_See also: _^<a!T397_Africa, history of_^>a__^<g_
Ewuare the Great of the Oba dynasty ruled the Kingdom of Benin (now southern _^<a!T23652_Nigeria_^>a_) from 1440 to 1473. According to oral tradition, Ewuare was a doctor, a warrior, a skilled magician, and a brave and wise man. He was an energetic and resourceful commander; more than 200 towns and villages came under his power. Ewuare and his successors pushed Benin's frontiers to the _^<a!T23651_Niger River_^>a_ in the east and southward to the sea. Benin artists, with their distinctive style, worked in bronze, wood, ivory, and raffia. It was Ewuare's Benin that the Portuguese discovered, and from which slaves, peppercorns, and ivory were traded._^<g_See also: _^<a!T405_African art_^>a_; _^<a!T3363_Benin, Kingdom of_^>a_; _^<a!T4855_bronzes_^>a_; _^<a!T20061_lost-wax process_^>a_; _^<a!T24432_oral history_^>a_; _^<a!T30103_slavery_^>a_; _^<a!T34794_West Africa_^>a__^<g_
This 14th- or 15th-century Peruvian ceremonial knife, an example of excellent metalworking, was one of the relatively few _^<a!T13916_gold_^>a_ and _^<a!T29908_silver_^>a_ objects of the pre-Columbian period to survive the pillaging and conquest of the Spanish _^<a!T7927_conquistadors_^>a_. The _^<a!T6869_Chimu_^>a_ were the dominant culture in _^<a!T25513_Peru_^>a_ from 1000 to 1450, and the _^<a!T16773_Inca_^>a_ dominated from 1450 to 1540. _^<g_See also: _^<a!T21754_metallurgy_^>a_; _^<a!T26470_pre-Columbian art and architecture_^>a_._^<g_
This _^<a!T2393_Aztec_^>a_ turquoise mosaic mask represents the plumed serpent god, _^<a!T27013_Quetzalcoatl_^>a_, one of the most important deities of ancient _^<a!T21724_Mesoamerica_^>a_. Quetzalcoatl, a creator god, is a unique symbol who controlled time cycles, weather for maize agriculture, and the daily periods of dawn and sunset. Aztec mosaic work revealed technical skill, ingenuity, and sophistication; such objects, sent to _^<a!T30557_Spain_^>a_ by the _^<a!T7927_conquistadors_^>a_, amazed European artists._^<g_See also: _^<a!T21817_Mexico, history of_^>a_; _^<a!T26470_pre-Columbian art and architecture_^>a__^<g_
The Chateau de Chenonceaux, an exceptionally beautiful example of both early and mature French _^<a!T27500_Renaissance_^>a_ architecture, is also outstanding for its beautiful setting and its gardens. Located on an islet in the Cher River about 196 km (122 mi) southwest of Paris, the chateau was restored in 1864, and today is state-owned._^<g_See also: _^<a!T6742_Chenonceaux, Chateau de_^>a_; _^<a!T12641_Francis I, King of France_^>a_; _^<a!T15564_Henry II, King of France_^>a_; _^<a!T27501_Renaissance art and architecture_^>a_._^<g_
The Cathedral of Saint Basil the Blessed in Red Square, _^<a!T22637_Moscow_^>a_, built from 1555 to 1560 during the reign of Ivan the Terrible, possesses an exotic splendor and an exuberance of form and decoration. Heavily carved towers and onion-shaped domes express its ornate style, which is derived from native church architecture._^<g_See also: _^<a!T6178_cathedrals and churches_^>a_; _^<a!T17264_Ivan IV, Tsar of Russia (Ivan the Terrible)_^>a_; _^<a!T22360_Mongols_^>a_; _^<a!T28284_Russia_^>a_; _^<a!T28285_Russia, history of_^>a_; _^<a!T28288_Russian art and architecture_^>a_._^<g_
The _^<a!T28443_Saint Bartholomew's Day Massacre_^>a_, a mass killing of French Protestants by Catholics, is remembered as a crime against humanity. In anticipation of a supposed Protestant plot, _^<a!T6184_Catherine de Medicis_^>a_ persuaded her son, Charles IX, to order the death of the _^<a!T16352_Huguenot_^>a_ leaders. On August 24, 1572, gruesome killings began in Paris; the killings were extended to the provinces, where they went on until October. Reports of victims range from 13,000 to 70,000. The massacre strengthened Protestant opposition to the house of _^<a!T33672_Valois_^>a_ and damaged France's relations with Protestant countries._^<g_See also: _^<a!T12625_France, history of_^>a_; _^<a!T26686_Protestantism_^>a_; _^<a!T27420_Reformation_^>a_._^<g_
The dome and towers of Istanbul's peerless Suleymaniye Mosque can be seen from the River Bosphorus in _^<a!T17238_Istanbul_^>a_, Turkey. One of the world's most sublime examples of religious architecture, the _^<a!T22648_mosque_^>a_ was designed by _^<a!T29966_Sinan_^>a_ and built during the reign of Suleyman (_^<a!T31352_Suleiman I_^>a_, r. 1520-66) as the _^<a!T24626_Ottoman Empire_^>a_ reached the apex of its power and glory._^<g_See also: _^<a!T17192_Islam_^>a_; _^<a!T17196_Islamic art and architecture_^>a_._^<g_
The 10th millennium BC marked several important developments in human prehistory and the beginning of the Neolithic Period, or New Stone Age (10,000 BC to 2,500 BC). Significant advances at this time, centered in the Middle East, included the domestication of wild animals--beginning with dogs and proceeding to sheep, goats, pigs, and later cattle--and the practice of agriculture._^<g__^<b__^<p_The Neolithic Revolution_^>p__^>b__^<g_The ability to raise crops and livestock triggered a major transformation in early human society that archaeologists have called the Neolithic Revolution. A stable food supply encouraged the establishment of permanent settlements, transforming nomadic hunter-gatherer clans into farming communities. The cultivation and storage of wheat, barley, oats, and other grains, the development of the wheel, plow, and other implements, and the domestication of animals for food and heavy labor all gave rise to new dietary staples, expanding urban centers, and diversified trades and crafts. As early as 8000 BC, the city of Jericho is believed to have had a population of more than 1,000. Catal Huyuk in southern Anatolia, a 7th-millennium BC farming village of mud-brick houses and shrines, covered some 32 acres._^<g_Clay pottery came into wide production and practical use in the Middle East, Europe, Africa, and South Asia during the 7th millennium BC. And metallurgy, which provided stronger tools, weapons, and other objects, also began appearing. The so-called Bronze Age occurred at different times in different parts of the world. In most areas, the development of bronze technology was preceded by the use of copper; the first evidence of copper and lead smelting dates to approximately 5400 BC in Asia Minor. During the next 3,000 years, corresponding to the rise of the earliest great urban civilizations, bronze production became commonplace and widespread._^<g__^<b__^<p_ The Rise of Civilization_^>p__^>b__^<g_By about 5000 BC, irrigation of the Tigris and Euphrates rivers in Mesopotamia supported an agricultural system capable of large surpluses, which in turn provided the wealth and diversification of labor to build several large city-states. These earliest urban societies of the Middle East were organized around the worship of local deities whose function it was to protect the city and ensure a plentiful harvest._^<g_History, the written record of human civilization, began about 3300 BC with the invention of writing systems in Sumer (southern Mesopotamia) and later Egypt. The earliest texts were inventories of agricultural products. The pictographs of Sumerian cuneiform were inscribed on wet clay tablets, which were then baked to make them hard. Egyptian hieroglyphics were normally written on paperlike sheets of papyrus._^<g_Technological innovations, social organization, and religious worship gave rise to a flowering of the visual arts and music. Architecture on a monumental scale found expression in the 3d millennium BC in the ziggurat at Ur (Mesopotamia), the site of religious rituals by king-priests, and the great pyramids of Egypt, elaborate royal tombs._^<g_The 31 dynasties of ancient Egypt (_^<i_c._^>i_3100 BC to 332 BC) were sustained by the rich floodplains of the Nile River, an abiding belief in the afterlife, and the worship of divine kings called pharaohs. One of the other great early civilizations, located in the fertile Indus Valley in what is now northwestern India and Pakistan, flourished between about 2500 BC and 1750 BC._^<g_Mastery of bronzeworking corresponded to the founding of the Shang Dynasty along the great rivers of China _^<i_c._^>i_1700 BC and the peak of the Minoan and Mycenean civilizations in the Aegean. From about 2500 BC to 1200 BC, the latter peoples established centers of metalworking and extensive trade routes into central Europe to obtain tin and copper._^<g__^<b__^<p_ Greece, Rome, and the Great Religions_^>p__^>b__^<g_New peoples, Israelites and Philistines, appeared in Canaan between 1200 BC and 1000 BC, and the earliest parts of the Old Testament--based on oral traditions--began to be written down in the next several hundred years. As the cult of the Hebrew god Yahweh competed with those of indigenous Canaanite deities, the religion of the ancient Greeks developed from the combined traditions of the Aegean civilizations, and the early Zhou (Chou) Dynasty in China established a state religion, which prevailed until modern times, based on the veneration of Heaven._^<g_Two of history's greatest religious and philosophical figures were contemporaries in the 6th century BC--Confucius (551-479 BC) in China and Buddha (_^<i_c._^>i_560-_^<i_c._^>i_480 BC) in India--though their approaches were very different. Confucius taught reverence for ancestral wisdom and social duty; Buddha taught release from suffering through renunciation of desire. In Greece during the same century, the pre-Socratic philosophers Thales, Anaximander, and Anaximenes laid the foundations of Western science by seeking natural rather than supernatural explanations of the world around them._^<g_Athens, the foremost power in a land of autonomous city-states, was the birthplace of democracy and the heart of classical Greek culture. During the 5th century BC, Western drama had its beginning in the tragedies of Aeschylus, Sophocles, and Euripides; Western historical writing began with Herodotus and Thucydides; the Western philosophical tradition began with the inquiries of Socrates; and Hippocrates wrote the first code of medical ethics. The Parthenon, the crowning achievement of Greek art and architecture, epitomized the guiding principles of Athenian culture: balance and harmony._^<g_By the 4th century BC, Macedonia had become the dominant state in Greece. Under Alexander the Great, the Macedonians conquered Persia and spread the Greek civilization east as far as the Indus valley. Also during this century, Greek philosophy reached its zenith in Plato and Aristotle, while the literature of Taoism began in China, and Rome began to emerge as a power in Italy._^<g_Rome defeated Macedonia and in 146 BC assumed a protectorate over Greece, at the same time imposing its rule on Spain and North Africa. Over the next century, Roman rule was extended into the Middle East and northwestern Europe. Troubled by political crises and civil war, the Roman Republic fell under the control of a succession of powerful military leaders. The most important of these were Julius Caesar, who was assassinated in 44 BC, and his adopted son Augustus, who became the first Roman emperor in 27 BC._^<g_With the help of advanced engineering in the construction of roads, bridges, and aqueducts, the Roman Empire controlled the entire Mediterranean world during the 1st and 2d centuries AD--a period of peace called the Pax Romana. In Palestine, meanwhile, Christianity began as a Jewish sect but quickly attracted non-Jewish followers._^<g_During the 2d century AD, the Han Dynasty in China was overthrown after ruling for 400 years, and the Maya civilization in Mesoamerica was flourishing. The classic age of ancient Indian civilization came under the Gupta dynasty beginning _^<i_c._^>i_320. At about the same time, the Roman Emperor Constantine I adopted Christianity, moved the capital east to Byzantium (Constantinople), and effected a split in the Roman Empire between the Latin Western and Greek Eastern. The latter would live for another 1,000 years as the Byzantine Empire._^<g_By late in the 4th century, the western Roman Empire was no longer able to resist pressures from various peoples along its frontiers. Partly by conquest and partly by peaceful infiltration, the Goths, Franks, Vandals, Anglo-Saxons, and other Germanic tribes won control. Rome was plundered in AD 410 and 455, and the last emperor was dethroned by Gauls in 476. That year is traditionally regarded as the end of the Classical period in Western civilization._^<g_
The period referred to as the Dark Ages began with the fall of Rome in AD 476 and lasted until the crowning of Charlemagne as the first Holy Roman Emperor in AD 800. So named because of a relative lack of historical written records rather than the dominance of "barbarians" in Western Europe or the outbreak of the plague--as are sometimes believed--the Dark Ages were in actuality a period of far-reaching cultural, religious, and intellectual development. The entire span from 476 to the 15th century is commonly referred to as the Middle Ages._^<g__^<b__^<p_Asia, Africa, and the Americas_^>p__^>b__^<g_During the 6th century AD, the Byzantine (Eastern Roman) Empire experienced renewed strength under Justinian I, who reconquered Italy and codified Roman law; the Hagia Sophia in Constantinople is a landmark of that century and that renewal. In India the 6th century marked the late Gupta period, the twilight of classic Indian civilization, and witnessed the maturation of Hindu philosophies._^<g_Muhammad (born _^<i_c._^>i_570), prophet of the new faith of Islam, led growing legions of followers in the conquest of Arabia. The Koran, considered by Muslims to be the actual words of God, was adopted as a standard text during the 7th century. After Muhammad's death in 632, Muslim Arabs spread the prophecy by holy war, conquering Persia and taking Syria and Egypt from the Byzantines. By the middle of the 8th century, the Islamic Caliphate extended from Central Asia to North Africa and southern Spain. Muslim armies were halted in their advance on Europe by Frankish troops at the Battle of Poitiers in 732._^<g_In the Far East, religion was spread through trade rather than conquest. Buddhism was carried from China to Japan and parts of Southeast Asia. During the 7th and 8th centuries, the Tang Dynasty in China controlled a vast pan-Asian empire stretching from Korea to the borders of Persia. The early Tang was the golden age of Chinese Buddhism; later, official patronage of Confucianism was revived, and the Chinese system of competitive civil service examinations based on the Confucian classics became fully established._^<g_During the so-called Dark Ages in Europe, the Arabic, Chinese, and Indian civilizations achieved major advances in science and technology, medicine, mathematics, and astronomy. The Hindu-Arabic method of numeration, which used a place-value system with 10 as its base, appeared in the 6th century. From China came the invention of paper, gunpowder, and the compass. Arab physicians wrote accurately about disease processes._^<g_In the Americas and Africa, as well, great cultures rose and fell. The metropolis of Teotihuacan in central Mexico, the Moche people in Peru, and the Maya culture in southern Mesoamerica thrived for hundreds of years but passed into oblivion by the end of the 9th century. In the ancient kingdom of Ghana (farther north than the present-day country), Soninke tribes gained control in the 8th century and built an empire that flourished on the trade of gold and salt for 300 years._^<g__^<b__^<p_The Middle Ages_^>p__^>b__^<g_The fragmented barbarian kingdoms that had predominated in western and central Europe after the fall of Rome were united under the rule of the Frankish king Charlemagne, heir to the Carolingian throne. Charlemagne, who converted the conquered peoples to Christianity, was crowned emperor by Pope Leo III on Christmas Day, AD 800. Although Charlemagne is regarded as the founder of the Holy Roman Empire, his realm dissolved after his death, and it was King Otto I of Germany who reunited the empire, had himself crowned emperor in 962, and founded the line of Holy Roman Emperors that lasted until the 19th century._^<g_In the 10th century Europe entered a prolonged period of revival. The armies of Western Europe were able to drive off various outside occupiers--Muslims from the south, Vikings from the North, Magyars from the east--and take to the offensive. In 1099 the Crusaders captured the Holy Land from the Muslims; in 1204 they seized the Eastern Empire from the Byzantines; and Christian armies in Spain gradually forced out the Moors._^<g_Organized according to the rules of feudalism, the economy and society of Western Europe also recovered and achieved heights unknown even under the Roman Empire. The church was reformed and revitalized, dominating life and culture. The papacy reached the zenith of its prestige under Pope Innocent III in the early 13th century. Romanesque art and architecture developed into the Gothic, whose aesthetic glory and engineering wonder found their highest expression in the cathedrals of Chartres, Reims, and Amiens._^<g_Europe's first great universities--at Bologna, Paris, and Oxford--all were founded before 1200. Saint Thomas Aquinas, in _^<i_Summa Theologiae_^>i_ (1267-73), created a synthesis between Aristotelian philosophy and the Christian faith that was one of the great intellectual achievements of medieval Europe._^<g_In England, the feudal system matured into a society of representative institutions, limited monarchy, and a contract theory of rights. The Magna Carta, exacted from King John by his rebellious barons in 1215, was a charter of liberties that embodied the resistance to unregulated monarchy. Parliament became a regular fixture of English government during the reign of Edward I (1270-1307)._^<g_Throughout Europe, meanwhile, interest in Asia was stimulated by the travel account of the 13th-century Venetian explorer and merchant Marco Polo. The Mongol Empire, which extended from the Pacific Ocean to the Black Sea, had been founded by Genghis Khan early in the century. By the time Marco Polo arrived in 1275, China was under the rule of Kublai Khan (the grandson of Genghis Khan); Polo became a favorite of the khan and spent 17 years roaming China in his service. _^<i_The Travels of Marco Polo,_^>i_ written in Venice about 1300, met with more than a little skepticism in European circles. When other travelers to China began verifying portions of his account, however, interest in trade with the Far East began to grow--and to influence the next generation of explorers._^<g_Europe in the 14th century (the "Later Middle Ages") suffered great famines, the Hundred Years' War between England and France, and the Black Death (bubonic plague)--which wiped out 75 million people, or between one-fourth and one-half of the continent's population. Those who survived, however, often had a better life, especially the peasants of Western Europe, who won both greater freedom and greater prosperity. The classic style, epitomized by Giotto, dominated Italian art, while the north of Europe reached the High Gothic. Dante Alighieri's _^<i_Divine Comedy_^>i_ (_^<i_c._^>i_1307-21), Giovanni Boccaccio's _^<i_Decameron_^>i_ (1348-53), and Geoffrey Chaucer's _^<i_Canterbury Tales_^>i_ (_^<i_c._^>i_1343-1400), classics of medieval European literature, evinced a humanism that would come to fruition in the Renaissance._^<g_
Fifteenth-century Europe saw an explosion of creative energy and a reawakening of the classical concerns for beauty, rational inquiry, and the human perspective. _^<i_Renaissance_^>i_, the French word for "rebirth," describes the radical and far-reaching changes that took place in European culture beginning in the 15th century. Historians view it as the demise of the Middle Ages and the first embodiment of the values of the modern world. It was an awakening that found its inspiration in ancient Greece and Rome--their works of art and literature, their interest in natural phenomena, and their emphasis on human values as opposed to religious beliefs._^<g__^<b__^<p_Art and Science_^>p__^>b__^<g_The artists of the early Renaissance sought to create art forms consistent with the appearance of the natural world and with their experience of human behavior, yet instilled with an ideal, transcendent beauty. In painting, the technique of perspective, a radical new conception of space and form, was consolidated early in the 15th century by Masaccio, Paolo Uccelo, and others. Flemish artists such as Jan van Eyck developed oil painting in the 1420s and '30s, further promoting the new aesthetic. In sculpture, Donatello's bronze _^<i_David_^>i_ (_^<i_c._^>i_1430-32), the first life-size, freestanding, nude statue since classical antiquity, epitomized the new humanism. In architecture, the massive dome of Florence Cathedral, designed in 1420 by Filippo Brunelleschi, was modeled after the Pantheon of ancient Rome and represented a clear break from the towering Gothic._^<g_The interest of Renaissance artists in perspective and anatomy presaged the appearance of a new kind of scientist, interested in both the theoretical knowledge of the academy and the technical skills of the artisan. The union of art and science was exemplified in the work of Leonardo da Vinci (1452-1519), who, in addition to being a painter, was an engineer and a student of biology, mathematics, physics, optics, and geology._^<g_Certainly the most important technological innovation of the 15th century (and perhaps of several centuries to come) was Johann Gutenberg's method of printing from movable type, introduced at about 1455. Classical works of literature and natural inquiry, being collected from monasteries and church libraries by Renaissance scholars, became available in a flood of new editions and translations--which in turn helped stimulate advances in science and technology._^<g__^<b__^<p_The Age of Exploration_^>p__^>b__^<g_The spirit of innovation in art and science coincided with far-flung explorations of the physical world. Exploration of the Atlantic Ocean by Italian, Spanish, and Portuguese mariners had begun with expeditions to the Canary Islands in the 14th century. By early in the 15th century, many of the problems of sailing on the open sea had been solved. Cosmographers associated with Prince Henry the Navigator devised ways to determine longitudinal position when out of sight of land by observing the stars._^<g_European explorers found sea routes to Asia and lands unknown in all directions, expanding the dominions of their patron countries--and the wealth of merchants. The voyages of Christopher Columbus to America (1492-1502) opened the Western Hemisphere to European hegemony. Vasco da Gama's voyage to India (1497-99) took him around the Cape of Good Hope and, for the first time by a European, outside the waters of the Atlantic. Portuguese explorations of West Africa gave birth, at midcentury, to the maritime slave trade._^<g__^<b__^<p_New Lights_^>p__^>b__^<g_The theme of new awakenings is no less appropriate to Asia and the Americas during the 15th century than it is to Europe. After a century of Mongol (Yuan Dynasty) control, China had come under the control of native rulers--the Ming--in 1368. By the middle of the 15th century, Ming emperors rebuilt Beijing and made it their capital, revived the nation's economy, and expanded overland trade with Central Asia. The reestablishment of native rule and the economic revival were accompanied by a flowering of scholarship and the arts that lasted two centuries._^<g_In the Middle East, the 15th century saw the twilight of an ancient Christian empire and the establishment of a new Islamic order. The Byzantine Empire, which had dominated the eastern Mediterranean for more than a thousand years, faced a growing challenge--both militarily and culturally--from Muslim Turks. The Ottoman Empire, which had begun as a small Islamic enclave in western Turkey, gradually extended its control and, in 1453, captured Constantinople (previously called Byzantium, later Istanbul). Among the actions taken by the new Ottoman rulers was to close all eastern Mediterranean ports to European vessels, thereby blocking overland trade routes to Asia. Circumventing this obstacle was one purpose of the century's historic ocean voyages by European explorers._^<g_In the Americas, the Aztec and Inca peoples established great empires during the 15th century. The Aztec (or "Mexica," as they called themselves) arose in Mesoamerica early in the century and grew steadily in power and influence. They acquired territory by warfare and captured prisoners for ritual sacrifice. In the great city of Tenochtitlan ("The Place of the Prickly Pear Cactus"), tens of thousands of prisoners were sacrificed at the temple of the sun god, Huitzilopochtli._^<g_The Inca Empire also took root early in the 15th century and grew to become the largest native empire of the South American continent. In the latter part of the century it began expanding from its base in the Cuzco region of the Peruvian Andes. Its defeat of the Chimu kingdom in what is now northern Peru opened up vast new territories. At its peak, the Inca Empire included about 12 million people and extended more than 2,000 miles along the western coast of South America. Among its greatest achievements--and characteristic features--was an infrastructure that included 12,000 miles of roads (many of them over mountainous terrain) and a well-organized, bureaucratically managed economy. The empire fell at the hands of the Spanish conquistador Francisco Pizarro in 1532--a time that would be called the "High Renaissance" in Europe._^<g_
Europe in the 16th century fostered and brightened the glow of the _^<a!T27500_Renaissance_^>a_, giving full vent to the _^<a!T16378_humanism_^>a_ and spirit of inquiry that had emerged in the previous century. This Age of Wonder brought a new way of looking at the world--not just a new aesthetic, a new politics, and a new kind of Christian faith, but an altogether broader vision that challenged medieval orthodoxies and cast behind old values. It was a period in Europe that encompassed the High Renaissance, the Protestant _^<a!T27420_Reformation_^>a_, and the Age of Discovery._^<g_In the 16th century also, Europe began to lead the world in technology. European firearms, although still very rudimentary, gave Spanish and Portuguese explorers an advantage over the peoples they encountered in Asia, America, and Africa. The major European powers took control of far-flung territories and sea routes, establishing whole new colonial empires. At the same time, several native dynasties and empires in Asia expanded their domains._^<g__^<b__^<p_New World Views_^>p__^>b__^<g_The cultural vision explored in the early Renaissance--art as a human aesthetic rather than an act of religious devotion--achieved a more powerful and mature expression in the first decades of the 16th century. The High Renaissance--whose works are characterized by a strong unity of composition and pictorial representation--was created by a few artists of genius, among them _^<a!T19458_Leonardo da Vinci_^>a_, _^<a!T21855_Michelangelo_^>a_, _^<a!T27240_Raphael_^>a_, and _^<a!T32581_Titian_^>a_. Masterpieces of the period include Leonardo's paintings _^<i_The Last Supper_^>i_ (_^<i_c._^>i_1495-98) and _^<i_La Giaconda_^>i_ (_^<i_Mona Lisa_^>i_, _^<i_c._^>i_1503-05); Michelangelo's sculptures the _^<i_Pieta_^>i_ (1498-1500), _^<i_David_^>i_ (1501-04), and _^<i_Moses_^>i_ (_^<i_c._^>i_1515), as well as his Sistine Chapel frescoes (1508-41); and Raphael's decorations for the state apartments in the Vatican (1511-15). German Renaissance art began with Albrecht _^<a!T10366_Durer_^>a_ and Matthias _^<a!T14572_Grunewald_^>a_, and continued with Hans _^<a!T15949_Holbein_^>a_ the Younger._^<g_The cultural Renaissance--with its emphases on human values, classical texts, and broad learning--was a natural precursor to upheaval in the Christian world. The Protestant Reformation, a movement to rid the Roman Catholic Church of medieval abuses and restore the doctrines of scripture, began in Germany in 1517 with the challenge by Martin _^<a!T20288_Luther_^>a_ to the doctrine of indulgences. His famous _^<i_95 Theses_^>i_, a litany of objections to papal policy that he posted on the church door in Wittenberg, quickly spread throughout Europe. The Frenchman John _^<a!T5530_Calvin_^>a_ and the Swiss Ulrich _^<a!T35933_Zwingli_^>a_ joined Luther in formulating a new Protestant interpretation of Christianity. Emphasizing a scripturally based faith, lay spirituality, and the autonomy of the individual conscience, Protestantism took root in Germany, Switzerland, Scandinavia, and France. In a further break with orthodoxy, the Church of England under Henry VIII declared its independence of Rome._^<g_The response defined the times as much as the challenge did. The Counter-Reformation, which affirmed traditional Catholic doctrine in opposition to Protestantism, was launched by the Council of _^<a!T32935_Trent_^>a_ (1545-63) and the founding of the _^<a!T17552_Jesuit_^>a_ order by St. _^<a!T16691_Ignatius Loyola_^>a_ in 1540. Jesuit missionary work in India and the Far East was begun by St. _^<a!T12639_Francis Xavier_^>a_ in the 1540s. In America, Spanish missionaries and conquistadors imposed Christianity on the Indians of Mexico and Peru. Jews, meanwhile, suffered persecution and expulsions across Europe._^<g_The Polish astronomer Nicolaus _^<a!T8086_Copernicus_^>a_ brought about the most literal change in how the world was viewed--and another confrontation with church doctrine. His 1543 treatise _^<i_On the Revolutions of the Heavenly Spheres_^>i_ laid the foundations of modern astronomy by suggesting that the Earth and other planets revolve around the Sun (heliocentric system) rather than accepting the long-standing (Ptolemaic) view that the Earth is the center of the universe._^<g__^<b__^<p_Contemporaneous with the Copernican Revolution were other scientific landmarks._^>p__^>b__^<g__^<a!T33919_Vesalius_^>a_ began the modern study of anatomy with _^<i_On the Structure of the Human Body_^>i_, published in the same year (1543) as Copernicus' breakthrough work. The Flemish cartographer Gerardus _^<a!T21658_Mercator_^>a_ in 1569 introduced the map projection with which his name would forever remain associated. The discovery of a new star by the Danish astronomer Tycho _^<a!T4555_Brahe_^>a_ in 1572 and his detailed observation of a comet in 1577 cast doubt on Aristotle's doctrine of the immutability of the heavens._^<g__^<b__^<p_New Politics, New Powers_^>p__^>b__^<g_Like art and scientific inquiry, politics became secularized in the 16th century, to be learned and practiced for its own purposes. In 1513, after the overthrow of the Florentine Republic by the _^<a!T21495_Medici_^>a_, an Italian statesman and military planner named Nicolo _^<a!T20498_Machiavelli_^>a_ penned a work titled _^<i__^<a!T26562_The Prince_^>a__^>i_, which gave new meanings to political power and government. An effective ruler, wrote Machiavelli, should be pragmatic rather than virtuous in his use of power; the pursuit of stable government may justify amoral actions. Politics was separated from theology and ethics; the end of retaining power might justify the means of violence or deception._^<g_Indeed the political history of 16th-century Western Europe was dominated by almost constant conflict among England, France, Spain, Germany, and the Netherlands over sovereignty and religion. In the first decades of the century, the _^<a!T14789_Habsburg_^>a_ Emperor Charles V fought Francis I of France in the _^<a!T17251_Italian Wars_^>a_ and sought a compromise with German Lutherans. The Peace of Augsburg (1555) divided Germany into Lutheran and Catholic states. At midcentury, Spain under the Catholic king Philip II dominated Western Europe and the Americas. France, meanwhile, was divided by a religious war between Catholics and _^<a!T16352_Huguenots_^>a_; Dutch Calvinists led the fight against Spanish rule in the Netherlands. Late in the century, England emerged as the leading nation of Protestant Europe. It challenged Spanish hegemony, aided the Dutch revolt, and in 1588 defeated the _^<a!T30564_Spanish Armada_^>a_. In France the Wars of Religion ended with the conversion of the Huguenot _^<a!T15566_Henry IV_^>a_ to Catholicism; the first _^<a!T4424_Bourbon_^>a_ king, Henry granted religious toleration by the Edict of Nantes in 1598._^<g_The spirit of exploration that began in the 15th century continued in the 16th. Armed with guns, missionary zeal, and a thirst for riches, Spanish, Portuguese, and French mariners set out in every direction. Early in the century, Spain colonized the West Indies; the Portuguese occupied Hormuz in the Persian Gulf, Goa in India, and Malacca on the Malay peninsula, gaining access to the rich spice trade of the East. From 1519 to 1522, a Spanish expedition under Ferdinand _^<a!T20637_Magellan_^>a_ (until his death) and Sebastian del Cano accomplished the first circumnavigation of the globe. Jacques _^<a!T6037_Cartier_^>a_ explored the St. Lawrence River for France in the 1530s. _^<a!T2574_Balboa_^>a_, _^<a!T26230_Ponce de Leon_^>a_, _^<a!T25941_Pizarro_^>a_, _^<a!T8214_Cortes_^>a_, _^<a!T8186_Coronado_^>a_, _^<a!T9182_de Soto_^>a_, and others laid claim to territories throughout the Americas. The Portuguese took control of Brazil. By 1540 Spain had built a vast empire in the New World, during the course of which it conquered the Aztec, Maya, and Inca peoples. In 1549, Portuguese missionaries and Spanish traders made the first European contact with Japan, then divided by civil war. (See also _^<a!T11533_exploration_^>a_.)_^<g_Elsewhere, the early 16th century saw the _^<a!T28401_Safavid_^>a_ dynasty rise to power in Iran and the Hindu empire of Vijayanagar reach its greatest extent, dominating southern India. _^<a!T2432_Babur_^>a_, a direct descendant of Genghis Khan, conquered northern India and in 1526 became the first emperor of the _^<a!T22250_Mogul_^>a_ dynasty. Meanwhile, the Turks under Suleiman the Magnificent (see _^<a!T31352_Suleiman I_^>a_) advanced into central Europe. The Muscovite ruler _^<a!T17264_Ivan the Terrible_^>a_ adopted the title _^<i_tsar_^>i_ in 1547 and established Russian dominance over the Tatars. In Japan, the feudal lord _^<a!T23757_Nobunaga_^>a_ began the process of reunification, completed by _^<a!T15749_Hideyoshi_^>a_ in 1590._^<g_
Historians often identify the 17th century as the beginning of the modern age in Western Civilization. It was the period in which people became aware that they had the power to change their environment, rather than regarding it as providentially ordained. Modern empirical science, both as a method of discovery and as a way of thinking, defined the idea of progress and set it in motion. The transition to the modern was characterized as well by a widespread process of secularization, begun in the Renaissance, in art and architecture, literature and scholarship, politics, philosophy, and society at large. By the end of the 17th century, the Age of Reason had begun; rational inquiry and empirical investigation had replaced religious doctrine, royal decree, and superstition as the measures of truth._^<g__^<b__^<p_The Scientific Revolution_^>p__^>b__^<g_Discoveries and theoretical formulations by a host of scientific luminaries revolutionized the fields of astronomy, physics, chemistry, medicine, and mathematics in the 17th century. _^<a!T13092_Galileo Galilei_^>a_ promoted the scientific revolution by attempting to verify physical laws experimentally and by linking the study of physics and astronomy with mathematics rather than traditional philosophy. In 1604 he formulated the basic law of falling bodies, which he verified by careful measurement. By 1609 he had finished building the first astronomical telescope and with it made observations supporting his belief in the Copernican (heliocentric) model of the solar system--a view for which he was imprisoned by the Roman Catholic Church. _^<a!T18245_Kepler's laws_^>a_ of planetary motion, published over the next ten years, further confirmed the Copernican theory._^<g_And there were other breakthroughs. In 1628, William _^<a!T15199_Harvey_^>a_ published _^<i_On the Motions of the Heart and Blood_^>i_, which correctly explained the human circulatory system and laid the foundation for modern medicine. Rene _^<a!T9454_Descartes_^>a_ in 1637 combined algebra and geometry in a new discipline called analytic, or coordinate, geometry. Evangelista _^<a!T32749_Torricelli_^>a_ devised the first barometer in the 1640s. Blaise _^<a!T25079_Pascal_^>a_ invented the first adding machine in 1645 and formulated Pascal's law, used in the operation of hydraulic systems, in 1653. The English chemist Robert _^<a!T4504_Boyle_^>a_ in 1662 developed the theory of gases that later became known as Boyle's Law._^<g_The revolution in physical science begun by Copernicus and carried on by Brahe, Kepler and Galileo was brought to fruition by Sir Isaac _^<a!T23573_Newton_^>a_. His _^<i_Principia_^>i_ (1687) provided a mathematical demonstration of the new physics, showing that all types of motion can be described by the same mathematical formulas. Twenty years earlier, Newton had provided science with a powerful new tool with his discovery (made independently by Gottfried Leibniz in Germany) of calculus._^<g_No figures better captured the essence of the period than Descartes in France and Francis _^<a!T2465_Bacon_^>a_ in England, both of whom stood at the confluence of modern science and philosophy. Descartes' method of systematic doubt established a new basis for certainty and led to his famous dictum _^<i_Cogito ergo sum_^>i_ ("I think, therefore I am"), a cornerstone of rationalist philosophy. Bacon encouraged scientific progress by popularizing an empirical approach to knowledge; in various writings he detailed the role of experience and experiment in confirming or refuting hypotheses. Bacon was also an early promoter of the Royal Society of London, one of several scientific and scholarly institutions established in the 17th century. Others included Rome's Accademia dei Lincei, France's Academie des Sciences, and Cardinal Richelieu's famous Academie Francaise for the regulation of the French language._^<g__^<b__^<p_Grace and Turmoil_^>p__^>b__^<g_Dominant political and cultural forces of the 17th century are represented in grand architectural monuments that still stand today. In France the classically elegant Palace of _^<a!T33902_Versailles_^>a_ was court to _^<a!T20098_Louis XIV_^>a_, the "Sun King," who reigned from 1643 to 1715 and made France the predominant power in Europe. In Rome, the Basilica of St. Peter's and St. Peter's Square epitomized the _^<a!T2827_baroque_^>a_ style, which captured the exuberance of the Counter-Reformation and became the dominant style in Western art for at least a century. In India the Mogul Emperor _^<a!T29556_Shah Jahan_^>a_ erected the marble _^<a!T31714_Taj Mahal_^>a_ ("crown of the palace"), perhaps the greatest achievement of Indo-Islamic architecture, to serve as a mausoleum for his beloved wife. In Persia, the Safavid shah _^<a!T20_Abbas I_^>a_ built the magnificent King's Mosque in Isfahan, his capital and one of the most beautiful cities in the world._^<g_The _^<a!T28401_Safavids_^>a_ and the _^<a!T22250_Moguls_^>a_ both reached the peak of their power and prestige during the 17th century, only to decline. The Safavid dynasty became vulnerable after the death of Abbas; it lost large tracts of territory to the Ottoman Turks, whose own empire reached its broadest expanse in the 1680s. The last of the great Mogul emperors, _^<a!T2233_Aurangzeb_^>a_, extended his realm into south India but precipitated the decline of the empire with costly wars. Elsewhere in Asia, the _^<a!T32644_Tokugawa_^>a_ shogunate (which would last more than 250 years) took root in Japan early in the century, and the Manchu _^<a!T26944_Qing_^>a_ overthrew the Ming in China at midcentury._^<g_In Europe the turmoil of the 17th century was not confined to the religious and scientific communities, nor was it unrelated to them. The fundamental clash of faiths was the _^<a!T32315_Thirty Years' War_^>a_ (1618-48), which began as a struggle between the Catholic Habsburg emperor and the Protestant states of the Holy Roman Empire; eventually it involved Spain, Denmark, Sweden, France, and the Netherlands. At war's end, marked by the Treaty of _^<a!T34834_Westphalia_^>a_, almost half the population of Germany was dead and large segments of Europe lay in ruins. It was exactly halfway through the Thirty Years' War, in 1633, that Galileo was condemned by the Inquisition for "suspicion of heresy."_^<g_Conflict between the king and Parliament of England during the latter half of the century ultimately led the way to constitutional monarchy. In the first of Europe's great political revolutions, friction between _^<a!T6594_Charles I_^>a_ and his Puritan-dominated Parliament erupted in civil war during the 1640s. Defeated, the king was tried, convicted, and executed in 1649. Oliver _^<a!T8531_Cromwell_^>a_, leader of the parliamentary army, ruled as protector until his death in 1658, and the monarchy was restored two years later. In 1688, Protestant dominance in England, Scotland, and Ireland was assured by the defeat and exile of the Catholic king, James II, in the _^<a!T13814_Glorious Revolution_^>a_._^<g__^<b__^<p_Literary Lights_^>p__^>b__^<g_The triumph of science in 17th-century Europe coincided with a sweeping literary revival. In England, Elizabethan drama reached its highest form in the work of William _^<a!T29561_Shakespeare_^>a_, whose writing career spanned the years _^<i_c._^>i_1588-1611. The first decade of the 17th century saw the creation of his greatest tragedies--_^<i__^<a!T14954_Hamlet_^>a__^>i_, _^<i__^<a!T20388_Macbeth_^>a__^>i_, _^<i__^<a!T18399_King Lear_^>a__^>i_, and _^<i__^<a!T24600_Othello_^>a__^>i_. Second only to Shakespeare among English poets, John _^<a!T22032_Milton_^>a_ produced his epic poem _^<i__^<a!T24947_Paradise Lost_^>a__^>i_ in 1667._^<g_Two of the greatest figures of Spain's Golden Age produced their major works early in the century--_^<a!T6397_Cervantes_^>a_, author of the comic novel _^<i__^<a!T9958_Don Quixote_^>a__^>i_ (1605-15), and the prolific dramatist and poet Lope de _^<a!T33808_Vega_^>a_. In France, the Golden Age saw dramatic masterpieces by Pierre _^<a!T8160_Corneille_^>a_, Jean _^<a!T27073_Racine_^>a_, and the satirist _^<a!T22293_Moliere_^>a_. And in Japan late in the century, the poet _^<a!T2907_Basho_^>a_ transformed the haiku from a social pastime into a major literary genre._^<g_
When a British military band played "The World Turned Upside Down" at the surrender to the American rebel army in 1781, it unknowingly sounded a theme much larger than a musical lament over a lost colony. The forces of change that had given birth to the modern secular age in the 16th and 17th centuries accelerated--and spread--in the course of the next 100 years. The 18th century has been called the Age of Reason and the Age of _^<a!T11063_Enlightenment_^>a_. New ideas about individual rights and freedoms flowed from the pens of great philosophers; new political and social forces were unleashed in revolution. It was an era of expanding European colonialism, a flourishing slave trade, and major shifts in wealth and power. It was a century of contradiction and upheaval--the world turned upside down._^<g_Freedom and Dominion_^<g_The political and social ideas commonly associated with the 18th century are those of the French _^<i_philosophes_^>i_, which included _^<a!T34198_Voltaire_^>a_, _^<a!T22439_Montesquieu_^>a_, Jean Jacques _^<a!T28146_Rousseau_^>a_, and others. Their thinking, however, was rooted in the work of two Englishmen, Sir Isaac _^<a!T23573_Newton_^>a_ and John _^<a!T19909_Locke_^>a_. In the 17th century, Newton had formulated basic laws of nature through careful observation and reasoning. Locke had argued that fundamental laws also could be derived for human nature and social interaction; individual rights and freedoms, he maintained, were absolute and inviolate._^<g_Voltaire, the great international figure of the 18th century, did much to popularize the ideas of Locke and Newton on the European continent; in his hands, the new philosophy was a powerful weapon for attacking old institutions and class inequities. Montesquieu, in _^<i_The Spirit of the Laws_^>i_ (1748), set forth the doctrine of separation of powers, which became a defining feature of constitutional democracy. Rousseau, in _^<i_The Social Contract_^>i_ (1762), argued that the only legitimate state was one based on the "will of the people."_^<g_The paradox of the Age of Enlightenment was that the spread of democratic values coincided with the peak of the African slave trade and the expansion of European colonialism. The _^<a!T30103_slave_^>a_ traffic was part of a growing commercial triangle between Europe, Africa, and North America. In the 18th century alone, up to 10 million people were taken captive in West Africa and transported in chains to European plantations in America._^<g_The long-standing sea power of the Spanish, Portuguese, and Dutch had gained them extensive territorial possessions in the Americas, Asia, and Africa. Early in the 18th century, however, their power had begun to wane. _^<a!T25540_Peter the Great_^>a_ introduced Western customs and institutions in Russia and established hegemony over the Baltic region; later in the century, _^<a!T6186_Catherine the Great_^>a_ brought further expansion of Russia's political and cultural influence. The War of Austrian Succession (1740-48) marked the emergence of _^<a!T26723_Prussia_^>a_ as a major power under _^<a!T12725_Frederick the Great_^>a_. Most of all, Britain and France emerged as the major European powers--and rivals. Their battle for dominance centered on two overseas fronts: India, where both nations intervened in the volatile situation created by the decline of the Mogul Empire; and North America, where Britain controlled the populous eastern seaboard and France controlled sparsely settled inland areas, Louisiana, and Quebec._^<g_The Anglo-French colonial struggle climaxed in the _^<a!T29492_Seven Years' War_^>a_ (1756-63). In India, British forces under Robert Clive won control of Bengal and effectively ended French influence in the subcontinent. In North America, the capture of Quebec by Gen. James Wolfe in 1759 forced France to surrender its colonial empire in Canada and the Mississippi valley. By the _^<a!T24989_Treaties of Paris_^>a_ in 1763, Britain acquired all of North America east of the Mississippi. It had become the world's leading naval and colonial power._^<g_Revolution_^<g_The values being championed by European Enlightenment thinkers were not lost on the colonists of British North America. Indeed, the calls for liberty and individual rights served as a catalyst, as well as the backdrop, for a growing alienation. The _^<a!T30827_Stamp Act_^>a_ of 1765 and other tax measures imposed by Parliament, plus the occupation of Boston by British troops in 1768, only heightened the disaffection. Fighting erupted in Lexington and Concord on April 19, 1775, and lasted more than six years. The first successful anticolonial movement in modern history, the _^<a!T1106_American Revolution_^>a_ was fought explicitly in the interest of such Enlightenment concepts as "unalienable rights" and the "will of the people." Those ideals--as well as the separation of powers, the separation of church and state, and a federated system of states--found concrete expression in the _^<a!T7979_Constitution of the United States_^>a_ (1788) and the _^<a!T3672_Bill of Rights_^>a_ (1791)._^<g_Across the Atlantic, the success of the American rebellion and the concepts espoused by the _^<i_philosophes_^>i_ triggered the violent and chaotic series of upheavals that comprised the _^<a!T12805_French Revolution_^>a_. In 1789 a mounting financial crisis, aggravated by the refusal of the nobility and clergy to submit to taxation, forced King _^<a!T20100_Louis XVI_^>a_ to convene the long-neglected _^<a!T30891_States-General_^>a_ (an assembly of clergy, nobility, and commoners). The populist estate (Commons) declared itself the National Assembly, thereby destroying the States-General. This first assertion of popular sovereignty inspired an uprising in Paris, marked by the storming of the _^<a!T2949_Bastille_^>a_. From 1789 to 1791 the nation was governed by the National Assembly, which issued the Declaration of the Rights of Man and the Constitution of 1791, establishing a constitutional monarchy. Within a year, however, the constitution collapsed. The king and queen were executed, the war became a revolutionary crusade, and internal opposition was crushed by the Reign of Terror. Not until the Constitution of 1799 was the repression over and stability achieved. The nation's leading general, _^<a!T23090_Napoleon Bonaparte_^>a_, seized the reins of power._^<g_Society and Culture_^<g_Among the other sea changes of the 18th century was a broad redistribution of wealth. Although the vast majority of Europeans were still peasants and the great wealth still lay in the hands of nobility, the merchant middle class came of age. The expansion of trade and the middle class, in turn, engendered a more extensive system of money and banking and a new class of bureaucrats. These were the people--bookkeepers, tax collectors, and lawyers--who most vigorously supported ideas of progress and urged laissez-faire (a government policy of "hands off") in trade and industry. The philosophy of economic freedom found its most enduring expression in the writings of the Scotsman Adam _^<a!T30168_Smith_^>a_. In his pioneering _^<i__^<a!T34624_Wealth of Nations_^>a__^>i_ (1776), Smith argued that unfettered competition would promote the general welfare and that the state should not interfere._^<g_In no field does the 18th century hold a more important place than in music. The period produced an amazing array of musical geniuses and new musical forms. In the first half of the century, George Frideric _^<a!T14999_Handel_^>a_ popularized the oratorio; Antonio _^<a!T34143_Vivaldi_^>a_ paved the way for the solo concerto; and Johann Sebastian _^<a!T2448_Bach_^>a_ brought baroque music to its pinnacle in his choral, keyboard, and orchestral works. The second half of the century saw the classical sonata and symphony come of age in the compositions of Franz Josef _^<a!T15295_Haydn_^>a_ and Wolfgang Amadeus _^<a!T22740_Mozart_^>a_. Christoph _^<a!T13827_Gluck_^>a_ reinvented the opera as a dramatic form; Mozart carried it to sublime expression. And the modern orchestra took shape; with the growth of middle-class audiences, subscription concerts and popular operatic performances began to replace court-sponsored music_^<g_
"The 19th century," wrote the English science fiction writer and social theorist H.G. Wells, "constituted a fresh phase of history." Like many others in the latter half of the century, the young Wells believed that science and technology could help create a more perfect world. In many circles, at least in the West, the idea of material "progress" was pursued with a vigor previously reserved for religious salvation. And though Wells, like others, would become disillusioned, the _^<a!T16861_Industrial Revolution_^>a_ brought changes to society and everyday life in Europe, Asia, and the Americas that no futurist ever could have fathomed. Conceptions of time, distance, and work--even beliefs about the origins and meaning of life--were fundamentally altered._^<g__^<b__^<p_Inventions and Innovations_^>p__^>b__^<g_The technological advances of the 19th century touched the fundamental structures and institutions of society--industry and labor, transportation, communication, and the arts. Important inventions of the late 18th century--including a practical _^<a!T30923_steam engine_^>a_ by James _^<a!T34585_watt_^>a_ in 1769 and the _^<a!T8277_cotton gin_^>a_ by Eli _^<a!T34943_Whitney_^>a_ in 1793--had set the stage. In 1804 the British engineer Richard _^<a!T32947_Trevithick_^>a_ constructed the first steam-powered _^<a!T19916_locomotive_^>a_, and three years later the American inventor Robert _^<a!T12961_Fulton_^>a_ launched the first successful _^<a!T30924_steamboat_^>a_. The process of vulcanization, discovered in 1839 by Charles _^<a!T14025_Goodyear_^>a_, converted _^<a!T28188_rubber_^>a_ into a tough elastic material suitable for manufacture; some 50 years later, John _^<a!T10333_Dunlop_^>a_ invented the pneumatic _^<a!T32554_tire_^>a_. In the mid-1850s came the technique of modern steel production, invented independently by Henry _^<a!T3540_Bessemer_^>a_ and William _^<a!T18186_Kelly_^>a_ (see _^<a!T17147_iron and steel industry_^>a_). In 1876, Nikolaus _^<a!T24618_Otto_^>a_ of Germany built the first successful _^<a!T16995_internal-combustion engine_^>a_, and in 1886 the German engineer Karl _^<a!T3401_Benz_^>a_ obtained a patent for the first _^<a!T2301_automobile_^>a_. The 1880s also brought the first practical automatic _^<a!T20500_machine gun_^>a_, introduced by Hiram Stevens _^<a!T21389_Maxim_^>a_, and the steam _^<a!T33177_turbine_^>a_, by Charles _^<a!T25055_Parsons_^>a_._^<g_Perhaps most far-reaching of all was the use of electricity to power a host of ingenious devices. Samuel _^<a!T22611_Morse_^>a_ successfully demonstrated the first _^<a!T32012_telegraph_^>a_ receiver in 1844; transatlantic cable came 22 years later. The Scottish-American scientist Alexander Graham _^<a!T3245_Bell_^>a_ developed and patented the first _^<a!T32020_telephone_^>a_ in 1876. Thomas _^<a!T10627_Edison_^>a_ in 1879 demonstrated the first practical electric light bulb, containing a carbonized cotton thread that burned continuously for 40 hours (see _^<a!T16774_incandescent lamp_^>a_). Edison's many other inventions included the _^<a!T25703_phonograph_^>a_ (1877) and movie _^<a!T26638_projector_^>a_ (1888); probably his greatest contribution, however was the construction of the world's first central electric-power station, opened in 1882 in New York City. The development of photographic reproduction, pioneered early in the century by Louis _^<a!T8844_Daguerre_^>a_ and others, radically changed perceptions of the world and culminated in the first motion pictures by the mid-1890s (see _^<a!T25724_photography, history and art of_^>a_ and _^<a!T12011_film, history of_^>a_)._^<g__^<b__^<p_Societies Transformed_^>p__^>b__^<g_The mechanization of heavy industry and transportation dramatically lowered the cost of manufactured goods, improved their quality, and made them more widely available. The impact on Western civilization was nothing less than a transformation from a rural agrarian society into an urban industrial society. The Industrial Revolution came first to Britain, where coal and iron ore were plentiful, waterways and seacoasts were navigable, and the political climate was conducive to free trade. Mines, textile mills, and factories replaced the domestic handicraft system. Farmers and tradesmen were absorbed into burgeoning urban populations. Supply fed demand, and fresh capital funded further expansion. Banking and insurance services lubricated the wheels of a market economy._^<g_Speeded by the construction of railroads, the Industrial Revolution spread from Britain to other European nations--newly independent Belgium, post-Napoleonic France, and pre-Bismarckian Prussia--in the 1830s and '40s. The idea of progress had taken root, manifest in a series of international exhibitions dubbed _^<a!T35403_world's fairs_^>a_. The achievements of 19th-century industrialism were celebrated at the Great Exhibition of 1851, held in London's iron-and-glass Crystal Palace. By mid-century, however, declining conditions in cities and mill towns and the widening gap between capitalist rich and working poor also sparked a literary and philosophical backlash. Charles _^<a!T9595_Dickens_^>a_ was the most prominent of the many writers who attacked the inequities and urban blight of the industrial age. The German social thinkers Karl _^<a!T21186_Marx_^>a_ and Friedrich _^<a!T11030_Engels_^>a_ predicted the revolt of the working class and the demise of capitalism in their _^<i_Communist Manifesto_^>i_ (1851)._^<g_Abundant natural resources and the spirit of free enterprise made the fledgling United States an ideal vehicle for industrialization. U.S. manufacturers took standard British techniques and added their own innovations to create a new method of production--the "American System." The innovations included continuous-process manufacturing and interchangeable-parts production, both of which drastically reduced labor costs and increased productivity. The new techniques were applied to bicycles, clocks, sewing machines, and virtually any other manufactured goods. With a rapidly expanding market held together by an extensive network of railroads (including a transcontinental link in 1869), the U.S. industrial economy grew at an astonishing rate. By the 1890s, the United States had surpassed Britain as the world's largest industrial producer; more importantly, a greater percentage of its national income came from manufacturing than from farming._^<g_The transformation did not come without pain. The defining event of the century for the United States--the _^<a!T7213_Civil War _^>a_--was, at the core, a conflict of economic systems and their attendant social institutions. Secession in the South and the outbreak of war in 1861 was the culmination of long-escalating differences between Northern manufacturing interests and Southern plantation owners over tariffs, slavery, and the uses of federal power. By the Confederate surrender in 1865, the dead numbered over 620,000--more than in all other U.S. wars combined._^<g_The Industrial Revolution touched virtually every part of the globe. The transformation of Japan from a secluded feudal society into a major military and industrial world power was completed in 1889 with the establishment of a Western-style constitutional monarchy under the Emperor Meiji (see _^<a!T21539_Meiji Restoration_^>a_). And the effects were felt even where no new mills or factories were constructed. The increased technological and military power of the European countries brought a new era of _^<a!T7636_colonialism_^>a_. To regions of Asia and Africa where previously there had been only European trading posts, the European nations now sent troops along with commercial agents, officials, and Christian missionaries. These areas were turned into markets for Europe's industrial products and suppliers of its raw materials. The British (India, Burma, Malaya, and portions of eastern, southern, and western Africa), French (Indochina and northern and western equatorial Africa), Germans (Tanzania and Namibia), Portuguese (Angola and Mozambique), Belgians (the Congo), and Dutch (Indonesia) all had extensive holdings._^<g__^<b__^<p_Life Sciences and the Arts_^>p__^>b__^<g_The 19th century also witnessed the beginning of the modern age in biology and medical science. In 1859, Charles _^<a!T8996_Darwin_^>a_ presented the theory of _^<a!T11480_evolution_^>a_ by natural selection in his landmark work _^<i_On the Origin of the Species_^>i_. The theory that human beings had evolved from other animal species was as controversial and revolutionary in the field of biology as Copernican heliocentrism had been in cosmology centuries earlier. In 1866 the Austrian monk Gregor _^<a!T21601_Mendel_^>a_ published the results of experiments that demonstrated the basic laws of heredity. His findings, the importance of which would not be realized until 1900, laid the foundation for the science of _^<a!T13401_genetics_^>a_. And in the 1880s, the French chemist Louis _^<a!T25105_Pasteur_^>a_ developed successful vaccines against rabies and anthrax. Considered the founder of _^<a!T21870_microbiology_^>a_, Pasteur demonstrated the relevance of germ theory to infectious disease, surgery, hospital care, and agriculture._^<g_The cultural legacy of the 19th century includes the music of Ludwig van _^<a!T3180_Beethoven_^>a_, Franz _^<a!T29092_Schubert_^>a_, Felix _^<a!T21607_Mendelssohn_^>a_, Johannes _^<a!T4563_Brahms_^>a_, Frederic _^<a!T6972_Chopin_^>a_, Franz _^<a!T19812_Liszt_^>a_, Giuseppe _^<a!T33866_Verdi_^>a_, and Richard _^<a!T34282_Wagner_^>a_; the paintings of the French Impressionists (see _^<a!T16761_impressionism_^>a_) and landscapes by the Japanese printmaker _^<a!T15945_Hokusai_^>a_; English Romantic poetry (see _^<a!T28001_romanticism_^>a_) and masterpieces of the _^<a!T23932_novel_^>a_ in English, French, and Russian (see also literature survey articles)._^<g_
Except for a brief respite in the 1920s, the first five decades of the 20th century were the bloodiest and most universally convulsive in human history. As weaponry became more mechanized, warfare intensified. Two world wars and an almost uninterrupted series of revolutions, civil wars, and other armed conflicts seemed to escalate in destructiveness. And the devastation was not confined to the battlefied. The global economic Depression of the 1930s was a quieter tragedy but more protracted and dispiriting. Hitler's "final solution" and Stalin's "great purges" were ethnically and politically motivated mass-murders. The atomic bombings of Hiroshima and Nagasaki in August 1945 obliterated whole cities. Humanity had demonstrated the ability to destroy itself completely._^<g_Upheavals_^<g_Among the causes of the "Great War," later to be called _^<a!T35394_World War I_^>a_, were rising nationalist sentiment across Europe, colonial and economic rivalries, the formation of hostile alliance systems, and a steady arms buildup, all of which contributed to growing international tension. The assassination of the Austrian archduke _^<a!T12687_Franz Ferdinand_^>a_ in Sarajevo in June 1914 was the spark that ignited the tinderbox. At the heart of the conflict were rival alliances: the Central Powers (principally Germany and Austria-Hungary) and the Triple Entente, or Allied Powers (Britain, France, and Russia; Italy joined in 1915, the United States in 1917)._^<g_The first war to be fought on land, at sea, and in the air, World War I brought more technological innovations than any conflict in history. Machine guns, battleships, land mines, barbed wire, engine-driven transport vehicles, and other products of 19th-century industrialization combined with such newer innovations as the airplane and poison gas to make killing more efficient. By the defeat of Germany in 1918, a staggering 8 million soldiers--one fourth of all the young men in Europe--lay dead. The Treaty of Versailles (see _^<a!T24993_Paris Peace Conference_^>a_) imposed a punitive peace on Germany; Austria and Hungary became separate states, Poland was restored, and the new nations of Yugoslavia and Czechoslovakia were founded._^<g_In Russia, meanwhile, the strains of the bloody conflict had caused a breakdown of the political system and social fabric. In the winter of 1917, food riots in several cities went unchecked by the military, and Tsar _^<a!T23612_Nicholas II_^>a_ was forced to abdicate. A provisional government was set up, but economic and social disorder remained pervasive. Seizing the opportunity, the Bolsheviks (Communists) under Vladimir Ilich _^<a!T19424_Lenin_^>a_ seized power in November (see _^<a!T28296_Russian Revolutions of_^>a_ 1917). It was the birth of the _^<a!T33435_Union of Soviet Socialist Republics_^>a_._^<g_In the United States, the 1920s were a time of prosperity and carefreeness. Spirits rose with the stock market. Flappers, roadsters, and racoon coats symbolized an optimism and exuberance that ignored rising debt and a ban on alcohol (see _^<a!T26633_prohibition_^>a_). Radio and motion pictures were a new cultural force. _^<a!T17477_Jazz_^>a_ set the rhythm, the future looked bright._^<g_Then the bottom fell out. The stock market crash of October 1929 marked the beginning of the Great Depression, the nation's worst crisis since the Civil War (see _^<a!T9422_Depression of the 1930s_^>a_). Banks and businesses failed by the thousands. Agricultural production plummeted, unemployment skyrocketed. At the depths of the Depression, in 1933, one out of every four American workers was out of a job. The _^<a!T23467_New Deal_^>a_, the ambitious recovery and reform program of President Franklin _^<a!T28032_Roosevelt_^>a_, instituted a host of lasting social programs but did not really end the crisis. Elsewhere the dislocations were equally severe. As world trade fell off, countries turned to nationalist economic policies that only exacerbated the problem. Unemployment commonly exceeded 25 percent. Inflation was so high that money sometimes was more useful to burn than to spend._^<g_In this context of economic desperation, political turmoil mounted steadily across Europe. In Germany, the punitive terms of the Versailles Treaty and the ravages of the depression gave rise to radical nationalism under the exhortations of Adolf _^<a!T15873_Hitler_^>a_. After consolidating power early in the 1930s, Hitler rearmed the nation and formed an alliance with Italy's Benito _^<a!T22948_Mussolini_^>a_, the founder of _^<a!T11735_fascism_^>a_. From 1936 to 1939, Hitler helped the Nationalists of Francisco _^<a!T12649_Franco_^>a_ win the _^<a!T30567_Spanish Civil War_^>a_, and in 1938 and 1939 he annexed Austria and Czechoslovakia. In Russia, meanwhile, Joseph _^<a!T30818_Stalin_^>a_ had come to power after Lenin's death in 1924 and had established dictatorial rule within five years. Brutally suppressing peasant resistance, Stalin began a massive industrialization program, financed by the seizure of farmlands and the "collectivization" of agriculture. Promoting a cult of adulation, he carried out a reign of terror against millions of real and perceived enemies throughout the 1930s. In the Far East, Japanese aggression against China led to full-scale war in July 1937 (see _^<a!T29986_Sino-Japanese Wars_^>a_). Within 18 months, Japan had conquered eastern China and turned its attention to Southeast Asia._^<g__^<a!T35397_World War II_^>a_ began in Europe when Germany, having concluded a nonaggression pact with the USSR (see _^<a!T23287_Nazi-Soviet Pact_^>a_), attacked Poland in September 1939. Within the next ten months, German forces overran and occupied Denmark, Norway, the Netherlands, and France. In June 1941, Hitler abandoned his pact with Stalin and invaded the USSR; in December, Japan brought the United States into the war with its attack on _^<a!T25220_Pearl Harbor_^>a_. The Soviet victory at Stalingrad in 1942-43, albeit at the cost of 750,000 troops, halted Germany's advance to the east. The Allied invasion of Italy in 1943 and of France in 1944 (see _^<a!T23823_Normandy Invasion_^>a_) ultimately sent the Germans into full retreat. Their surrender in May 1945, however, did not come soon enough for the 6 million European Jews murdered in Nazi death camps. The Allied explosion of atomic bombs over Hiroshima and Nagasaki three months later killed more than 125,000 Japanese civilians but ended the war in the Pacific._^<g_New Visions_^<g_In the first decades of the 20th century, the cultural and intellectual communities of the West witnessed a revolution the likes of which had not been seen since the Renaissance. _^<a!T8615_Cubism_^>a_, a new style of painting invented by Pablo _^<a!T25766_Picasso_^>a_ and Georges _^<a!T4611_Braque_^>a_, seemed to capture the fragmentation and dislocations of modern industrial society. No less shocking to the cultural establishment--but no less influential to future artists--was the dissonant music of Igor _^<a!T31190_Stravinsky_^>a_; his score for Serge Diaghilev's ballet _^<i_Rite of Spring_^>i_ caused a riot at its debut performance in Paris in 1913._^<g_The decades before World War I also witnessed two major intellectual breakthroughs. Beginning with his book _^<i_The Interpretation of Dreams_^>i_ (1900) and continuing in case studies and other writings, the Austrian physician Sigmund _^<a!T12826_Freud_^>a_ pioneered a new field called _^<a!T26744_psychoanalysis_^>a_. His investigations of the unconscious mind profoundly altered our view of ourselves and helped shaped the modern age. And in 1915, after a decade of work, the German physicist Albert _^<a!T10718_Einstein_^>a_ published the definitive form of his general theory of _^<a!T27474_relativity_^>a_. It is considered one of the great achievements of theoretical physics, setting the entire discipline on a new plane._^<g_World War I seemed to heighten the fractured and rebellious character of modern artistic expression, with a frequent emphasis on spiritual desolation. _^<a!T8831_Dada_^>a_, which rejected all established aesthetic values, was founded during the war years in Switzerland. Perhaps the two most influential literary works of the century--T.S. Eliot's _^<i_The _^<a!T34516_Waste Land_^>a__^>i_ and James Joyce's _^<i__^<a!T33377_Ulysses_^>a__^>i_--both appeared in 1922, and both had alienation as a central theme. _^<i_Rhapsody in Blue_^>i_ (1924) and other musical compositions by George _^<a!T13536_Gershwin_^>a_ captured the carefree spirit of the Roaring Twenties, but F. Scott Fitzgerald evoked its inner emptiness in his virtuoso novel _^<i_The _^<a!T14305_Great Gatsby_^>a__^>i_ (1925). Another novel, _^<i_The _^<a!T14228_Grapes of Wrath_^>a__^>i_ (1939) by John Steinbeck, portrays the lives of American migrant workers during the Depression and stands as a literary landmark of that time. But no work of art better captures the essence of the first half of the 20th century than Picasso's 1937 painting _^<i_Guernica_^>i_. Inspired by the bombing of a small town during the Spanish Civil War, the semi-abstract work is a haunting vision--in black, white, and gray--of the horrors of war._^<g_
The year 1945 marked a watershed in the 20th century. World War II was over, and the map of Europe was redrawn for the second time in the century. The United States and the Soviet Union emerged as the world's major powers, and new lines--as much ideological as geographical--were drawn in international relations. The post-World War II era would be defined by competition between the Communist bloc and the democratic world amid the ever-present risk of nuclear disaster. Space exploration, electronic communications, and advances in medicine set new horizons in technology. Nuclear arms reductions, the environmental movement, and institutions for settling disputes were signs of a new global outlook. Damaged ecosystems, rampant poverty, the _^<a!T522_AIDS_^>a_ epidemic, and ongoing political and ethnic strife defined the need._^<g_The Cold War_^<g_At the _^<a!T35541_Yalta Conference_^>a_ and other meetings during and after World War II, leaders of the Allied nations began discussing the organization of the postwar world and the establishment of an international peacekeeping body. The latter came to pass with the ratification of the _^<a!T33451_United Nations_^>a_ Charter on Oct. 24, 1945, by 51 member-states. Organizing the postwar world would prove more problematic. Relations between the USSR and other Allies had deteriorated into mutual distrust. The rift widened as the Soviets began installing Communist puppet regimes throughout Eastern Europe. In March 1946, British Prime Minister Winston _^<a!T7096_Churchill_^>a_ declared: "From Stettin in the Baltic to Trieste in the Adriatic, an iron curtain has descended across the Continent." _^<g_The _^<a!T7568_cold war_^>a_--the strategic and political struggle between the United States (with its Western European allies) and the Soviet Union (with its Communist satellite states)--escalated steadily in the immediate postwar period and dominated international affairs for the next 40 years. The division of Germany into rival states in 1949 (see _^<a!T13522_Germany, history of_^>a_), the takeover of China by Communist forces under _^<a!T20966_Mao Zedong_^>a_ the same year, and the successful testing of nuclear bombs by both the USSR and China in the early 1950s served to broaden the tensions and heighten the fears. The first phase of the Cold War culminated in the _^<a!T18614_Korean War_^>a_ (1950-53), in which the United States led a UN-sponsored "police action" to help South Korea against Communist North Korea and its ally, China._^<g_The _^<a!T3470_Berlin Wall_^>a_, the preeminent symbol of conflict between the Communist and non-Communist worlds, was constructed in 1961 to stem the flow of workers migrating from East Germany to West Germany. The Cold War reached its peak in the _^<a!T8612_Cuban Missile Crisis_^>a_ of 1962, in which U.S. President John _^<a!T18212_Kennedy_^>a_ ordered a naval blockade of Cuba--and risked direct military confrontation with the USSR--to prevent the installation of nuclear missiles on the island. A series of _^<a!T1830_arms control_^>a_ agreements beginning in the mid-1960s slowed the buildup of weapons, but the ideological rivalry and competition for influence between the two superpowers continued until the demise of Soviet Communism in the 1990s._^<g_The Independence Movement and Local Conflicts_^<g_Even as the superpowers struggled for global strategic advantage, the national independence movement gathered steam after World War II. In a number of prominent cases, independence led to civil war or international conflict. In India, the passive resistance movement of Mohandas _^<a!T13171_Gandhi_^>a_ led to independence in 1947. Israel and Indonesia followed in 1948. In the case of Israel, independence was followed almost immediately by war with neighboring Arab states; the conflict remained chronic and intractable for decades (see _^<a!T1636_Arab-Israeli Wars_^>a_). In 1954, French Indochina (Vietnam, Laos, and Cambodia) became independent. Vietnam was divided between a Communist North and a pro-Western South, planting the seeds of the _^<a!T34008_Vietnam War_^>a_ of the 1960s and '70s. In Cambodia, the brutal rule of the Communist party (see _^<a!T18310_Khmer Rouge_^>a_) in the mid-1970s left at least one million Cambodians dead. In Africa, most of the former British, French, and Belgian colonies won independence in the early 1960s. United Nations peacekeeping troops helped quell a series of rebellions in _^<a!T7884_Zaire_^>a_ (then known as the Congo) in 1960-63._^<g_The next great wave of independence came with the dissolution of the Soviet satellite system in 1990 and the breakup of the USSR itself in 1991. The 15 former Soviet republics became 15 independent states (see _^<a!T33435_Union of Soviet Socialist Republics_^>a_ and articles on individual states). Throughout Eastern Europe, moreover, the removal of Communist control unleashed pent-up nationalist sentiments and age-old ethnic feuds. Beginning in 1991 nationalism tore up the former Yugoslavia, with bitter ethnic fighting ravaging Croatia and Bosnia-Hercegovina (see _^<a!T35725_Yugoslav War_^>a_)._^<g_U.S. Affairs_^<g_The effects of the Cold War on U.S. domestic affairs were evidenced in a variety of events, attitudes, and political trends--the fear and turmoil of the "McCarthy era" (see _^<a!T20401_McCarthy, Joseph R._^>a_); the birth and growth of the "military-industrial complex"; the polarization over the Vietnam War; and the definition of political issues in left-right, liberal-conservative terms. But there were other important forces at work. During the 1950s, television emerged as a powerful new cultural influence (see _^<a!T27108_radio and television broadcasting_^>a_); the _^<a!T31306_suburbs_^>a_ burgeoned as a place to live and a lifestyle. In the late 1950s and 1960s, the _^<a!T7205_civil rights_^>a_ movement aroused national opinion against Southern segregation and forced passage of major federal legislation; the nation's racial problems, however, remained deep-rooted. The assassinations of President John F. _^<a!T18212_Kennedy_^>a_ in November 1963, the Rev. Martin Luther _^<a!T18389_King_^>a_, Jr., in April 1968, and Sen. Robert F. _^<a!T18214_Kennedy_^>a_ in June 1968 left scars in the national psyche. The Vietnam War and the _^<a!T34561_Watergate_^>a_ scandal tested the principles and institutions of American democracy._^<g_New Horizons_^<g_Just as technology had provided the ultimate destructive force, so too did it provide the means to expand the human experience and extend human life. The age of _^<a!T30541_space exploration_^>a_ began in 1957 with the launching by the Soviet Union of _^<i_Sputnik 1_^>i_, the first artificial satellite. The early phase of human space flight culminated on July 16, 1969, with the landing on the Moon of the crew of _^<i_Apollo 11_^>i_ (see _^<a!T1572_Apollo program_^>a_). The subsequent decades featured extended orbital missions, soft-landing and flyby satellite probes of other planets, and the American _^<a!T30546_Space Shuttle_^>a_ program._^<g_The view of Earth from space and mounting scientific evidence of damage to the environment raised consciousness about protecting the planet's resources and ecosystems. Research intensified, anti-pollution legislation was passed, and forums were organized to coordinate international efforts. But progress seemed slow. (See _^<a!T7941_conservation_^>a_.)_^<g_Medical science, however, progressed by leaps and bounds. The development of the _^<a!T15361_heart-lung machine_^>a_ in the early 1950s made extensive heart surgery possible.The first successful heart transplant was performed in 1967. The introduction of Cyclosporin, an effective anti-rejection drug, in the early 1980s radically improved the success rate of heart and other organ transplants (see _^<a!T32876_transplantation_^>a_). In 1982 human insulin became the first commercially available product of _^<a!T13398_genetic engineering_^>a_, seen as a promising technology of the future. Progress was made in the fight against _^<a!T5671_cancer_^>a_. A cure for _^<a!T522_AIDS_^>a_ remained the prayer of millions. The advent of electronic communications and digital information processing was seen by some as a major turning point in history. Beginning with direct airwave signals and proceeding to satellite transmissions and cable networks, the _^<a!T21246_mass media_^>a_ became a powerful social and political force. News and information from around the world were shared instantly, penetrating ideological and cultural walls. With ever more powerful silicon chips and innovative software, _^<a!T7809_computers_^>a_ were able to process more information and found new uses in business and industry, science and medicine, the arts and leisure--virtually every aspect of modern life. The rapidly expanding number of users and the development of sophisticated networking and data-access technologies held promise of a quantum leap in human communication at the start of the new millennium._^<g_
French explorer and cartographer Samuel de Champlain is known primarily as the founder of Quebec. He was also the first European to find the Ottawa River and several lakes, including Champlain, Ontario and Huron. He made the discoveries while seeking, among other objectives, a route to Asia (1603-33)._^<g_See also: _^<a!T5639_Canada, history of_^>a_; _^<a!T6497_Champlain, Samuel de_^>a_; _^<a!T26984_Quebec (province)_^>a_._^<g_
A group of English and Dutch separatists seeking religious freedom sailed on the _^<a!T21417_Mayflower_^>a_ from Southhampton, England, on September 16, 1620 and landed in Plymouth, Mass., on December 26. The ship carried 102 passengers called _^<a!T25818_Pilgrims_^>a_ who sought to establish a colony in the New World._^<g_See also: _^<a!T4528_Bradford, William_^>a_; _^<a!T4711_Brewster, William_^>a_; _^<a!T26062_Plymouth Colony_^>a_._^<g_
The first written constitution was the Fundamental Orders of Connecticut, adopted in 1639. Settlers from the first permanent Connecticut River valley towns of Hartford, Wethersfield, and Windsor met in Hartford to frame the orders, a body of laws by which they would govern themselves._^<g_See also: _^<a!T7908_Connecticut_^>a_; _^<a!T33462_United States, history of the_^>a_._^<g_
The French explorer La Salle was the first European to sail the lower Mississippi River in 1682. Like other explorers of his time, La Salle made the discovery while seeking a route to Asia through the North American continent. He also engaged in the fur trade while in North America._^<g_See also: _^<a!T11533_exploration_^>a_; _^<a!T18824_La Salle, Robert Cavelier, Sieur de_^>a_._^<g_
The Masjid-i-Shah, or Royal Mosque, in Isfahan, Iran, is a 17th-century structure that is part of a large open space called the Mayan-i-Shah. Built during the Safavid Dynasty reign of Abbas I, the Masjid-i-Shah is illustrative of the Iranian mosque style in its use of colorful tiles and mosaics._^<g_See also: _^<a!T17196_Islamic art and architecture_^>a_; _^<a!T28401_Safavids_^>a_._^<g_
In 1644, the Manchus swept in from the north, seized Beijing and started the _^<a!T26944_Qing_^>a_ dynasty, which would rule until 1911. Under Kangxi (r. 1661-1722), and Qianlong (r. 1735-96), Chinese hegemony over Asia extended over an area greater than that of any previous dynasty except the Mongol Yuan._^<g_See also: _^<a!T6873_China, history of_^>a_; _^<a!T18025_Kangxi, Emperor of China (K'ang-hsi)_^>a_._^<g_
Even as their empire began to decline, the Ottoman Turks continued to seek new lands. In 1669, they seized the Mediterranean island of Crete and held onto it until the Cretans launched a successful revolt in 1898. The _^<a!T24626_Ottoman Empire_^>a_ reached its peak in the 16th century and slowly collapsed._^<g_See also: _^<a!T348_Aegean civilization_^>a_; _^<a!T21512_Mediterranean Sea_^>a_._^<g_
The microscope dates from the construction of compound-lens systems, which occurred between 1590 and 1610. Dutch biologist Antoni van Leeuwenhoek, considered to be the founder of microbiology, conducted his groundbreaking work with single lenses that he constructed._^<g_See also: _^<a!T19343_Leeuwenhoek, Antoni van_^>a_; _^<a!T24425_optics_^>a_._^<g_
Johannes _^<a!T18244_Kepler_^>a_, a German astronomer who was one of the first backers of the sun-centered theory of Copernicus, discovered three laws of planetary motion (see _^<a!T18245_Kepler's laws_^>a_). He published the first two laws in 1609 in _^<i_Astronomia nova_^>i_, and the third in 1619 in _^<i_Harmonices mundi_^>i_. Using Mars as an example, Kepler showed that the planets move in elliptical, not circular, orbits around the sun._^<g_See also: _^<a!T2081_astronomy, history of_^>a_; _^<a!T8086_Copernicus, Nicolaus_^>a_._^<g_
A 17th-century Italian mathematician and astronomer who pioneered the use of the telescope, _^<a!T13092_Galileo Galilei_^>a_, was a firm supporter of the Copernican heliocentric system. That support, however, made Galileo a target of the Inquisition. In 1633, Galileo was convicted of heresy and sentenced to life in prison, but his sentence was quickly changed to house arrest. He died at his villa in Arcetri in 1642._^<g_See also: _^<a!T8086_Copernicus, Nicolaus_^>a_; _^<a!T15459_heliocentric world system_^>a_; _^<a!T29134_science, history of_^>a_._^<g_
The word "cell" was first used by 17th-century scientist Robert _^<a!T16083_Hooke_^>a_, who studied minute anatomical structures through the microscope. His _^<i_Micrographia_^>i_ (1665) underscored the great potential of the microscope for biological examinations. Hooke also demonstrated that supplying fresh air was one of the functions of respiration._^<g_See also: _^<a!T6298_cell_^>a_; _^<a!T21870_microbiology_^>a__^<g_
Sir Issac _^<a!T23573_Newton_^>a_, widely considered to be the greatest scientist of his or any other time, designed and constructed the first reflecting telescope. In 1687, Newton compiled his theories on gravity, motion and other subjects in _^<i_Principia_^>i_, which underscored the fundamental contributions he made to the development of science._^<g_See also: _^<a!T24083_observatory, astronomical_^>a_._^<g_
The Romanov Dynasty ruled Russia from 1613 until the February Revolution of 1917. The dynasty started when Michael Romanov was elected tsar by the National Assembly in 1613. Michael Romanov was the grandnephew of Anastasia Romanov, who was the wife of Ivan IV, the first tsar of Russia._^<g_See also: _^<a!T17264_Ivan IV, Tsar of Russia (Ivan the Terrible)_^>a_; _^<a!T27999_Romanov (dynasty)_^>a_._^<g_
An expedition (1581-82) of Cossack _^<a!T35629_Yermak Timofeyevich_^>a_ began the conquest of Siberia, which continued through the 17th century. Siberia's natural resources were exploited and added to the wealth of the Russian Empire. From early in the 17th century, Siberia was also used as a penal colony._^<g_See also: _^<a!T28285_Russia, history of_^>a__^<g_
Peter I, known as Peter the Great, was the tsar of Russia between 1682 and 1725 and the first Russian emperor, named in 1721. He built a vast military apparatus and sought to turn Russia into a westernized society. As a result, he constructed the foundation of the modern Russian state._^<g_See also: _^<a!T25540_Peter I, Emperor of Russia (Peter the Great)_^>a_; _^<a!T28285_Russia, history of_^>a_._^<g_
The 1606 Peace of Vienna ended a two-year war between Hungary and the _^<a!T14789_Habsburg_^>a_ dynasty over the persecution of Protestants following the Reformation. Istvan Bocksay, the prince of Transylvania and Hungary, allied with Turkish forces in the war and secured religious freedom for Hungarian Protestants_^<g_
An English philosopher, scientist, and political theorist, Thomas _^<a!T15894_Hobbes_^>a_ saw constant war as the natural state of humans and self-interest as the spur of all actions. In 1651, Hobbes published his main work, _^<i__^<a!T19541_Leviathan_^>a__^>i_, in which he described human life as "nasty, brutish and short."_^<g_See also: _^<a!T25683_philosophy_^>a_; _^<a!T30289_social contract_^>a_._^<g_
The bloodless overthrow in 1688 of the Roman Catholic _^<a!T17402_James II_^>a_ of England and the accession to the throne of his daughter Mary II and her Dutch Protestant husband, William III, is known as the _^<a!T13814_Glorious Revolution_^>a_. Within a year, William and Mary had constructed the beginnings of the modern constitutional monarchy._^<g_See also: _^<a!T3672_Bill of Rights_^>a_; _^<a!T14297_Great Britain, history of_^>a_._^<g_
Spanish writer Miguel de _^<a!T6397_Cervantes Saavedra_^>a_'s greatest work, _^<i_Don Quixote_^>i_, is a 17th-century satire that is one of the most popular books ever written. Published in two parts (1605 and 1615), the story follows a dreamer, Don Quixote, who sees himself as a knight-errant who must confront giants and rescue women while wooing his lady._^<g_See also: _^<a!T1494_anti-hero_^>a_; _^<a!T9958_Don Quixote_^>a_; _^<a!T30572_Spanish literature_^>a_._^<g_
A pan-European struggle for power, the _^<a!T32315_Thirty Years' War_^>a_ (1618-48) was actually a series of evolving conflicts fought mainly on German soil. It was the last major European battle in the wake of the Reformation, and it was the first continental struggle for power. In some areas of Germany, the conflict wiped out 50 percent of the population._^<g_See also: _^<a!T11397_Europe, history of_^>a_; _^<a!T13522_Germany, history of_^>a_; _^<a!T34835_Westphalia, Peace of_^>a_._^<g_
The fountain pen has a curious history. Some historians claim it was invented in France in 1657. Others credit 19th-century American inventor Lewis E. Waterman with the refinements that made it a popular writing instrument. Fountain pens were an indispensable tool until the invention of ballpoint pens in the mid-20th century._^<g_See also: _^<a!T16908_ink_^>a_; _^<a!T25311_pen_^>a_; _^<a!T35444_writing systems, evolution of_^>a_._^<g_
Considered one of the greatest works of English literature, _^<i_Paradise Lost_^>i_ (published 1667) is an epic story based on the Christian theme of temptation and salvation. Milton saw the work as an alternative to the non-Christian material found in the classical epics._^<g_See also: _^<a!T11047_English literature_^>a_; _^<a!T22032_Milton, John_^>a_; _^<i__^<a!T24947_Paradise Lost_^>a__^>i_._^<g_
The Tokugawa shogunate emerged as the most powerful faction among many seeking to rule _^<a!T17427_Japan_^>a_ in the early-17th century. From 1603 to 1867, the shogunate dominated Japan. In the middle of the 17th century, it adopted a policy of national isolationism that stood until 1868._^<g_See also: _^<a!T17428_Japan, history of_^>a_; _^<a!T29751_shogun_^>a_; _^<a!T32644_Tokugawa (family)_^>a_._^<g_
By 1638, the Tokugawa shogunate consolidated its policy of national isolation in _^<a!T17427_Japan_^>a_. Alarmed by the influence of Europeans, the shogunate barred foreigners and refused to allow Japanese travel overseas. The policy persisted until 1868 when the Emperor Meiji fully restored relations between Japan and the rest of the world._^<g_See also: _^<a!T17428_Japan, history of_^>a_; _^<a!T32644_Tokugawa (family)_^>a_._^<g_
_^<a!T29556_Shah Jahan_^>a_ became emperor of the Mogul Dynasty in 1628. It flourished culturally under his rule. Among other conquests, Shah Jahan expanded Mogul territory into northern Afghanistan and Ahmadnagar and Golconda. He built the Taj Mahal at Agra and the Divan-e Amm and the Divan-e Khass in Delhi before his son, _^<a!T2233_Aurangzeb_^>a_, became emperor in 1658._^<g_See also: _^<a!T22249_Mogul art and architecture_^>a_; _^<a!T22250_Moguls (dynasty)_^>a__^<g_
The _^<a!T31714_Taj Mahal_^>a_ of Agra, India, was completed in 1648 by _^<a!T29556_Shah Jahan_^>a_, Mogul Emperor of India (1628-58). The monumental structure served a dual purpose: as a representation of the throne of God in paradise and as the mausoleum for the emperior's consort, Arjunand Banu Begum, who was also known by the title Taj Mahal._^<g_See also: _^<a!T16803_Indian art and architecture_^>a_; _^<a!T29556_Shah Jahan, Mogul Emperor of India_^>a_._^<g_
_^<a!T2233_Aurangzeb_^>a_ was the sixth emperor of the Mogul dynasty in India and the last to exercise effective command over the empire. Aurangzeb came into power in 1658, and his rule enjoyed stability until about 1680, when a revolt compelled the emperor to mount a series of campaigns against the Hindus. When he died in 1707, his empire was in disarray._^<g_See also: _^<a!T16800_India, history of_^>a_; _^<a!T22250_Moguls (dynasty)_^>a_._^<g_
_^<a!T5458_Calcutta_^>a_, a city in eastern _^<a!T16799_India_^>a_, was founded by the British East India Company in 1698. The company acquired several villages and linked them under a common administration. The name Calcutta may be derived from _^<i_Kalikata_^>i_, the mythological landing place for the goddess Kali._^<g_See also: _^<a!T10511_East India Company, British_^>a_; _^<a!T16800_India, history of_^>a_._^<g_
How does the universe operate? How does the Earth relate to the other planets? The way people answered these questions changed radically during the 17th and 18th centuries, as a result of fundamental discoveries by a train of luminaries headed by Nicolaus _^<a!T8086_Copernicus_^>a_._^<g_In 1543, Copernicus breached the wall of religion and mysticism by showing, with mathematical reasoning, that the Earth revolved around the Sun. This called into question the Earth-centered model, which had stood for centuries in the West. Danish astronomer Tycho _^<a!T4555_Brahe_^>a_, too, went on the offensive against the established order. In 1572, his observation of a _^<a!T23923_nova_^>a_ chipped away at the notion of the immutability of the heavens._^<g_Discoveries and theories supporting the mechanistic view of the universe accelerated in the 17th century. Johannes _^<a!T18244_Kepler_^>a_ formulated three planetary laws, including one that stated that all planets move in elliptical orbits around the Sun. _^<a!T13092_Galileo Galilei_^>a_, whose work and life became trapped in the web of the Roman Catholic Church's reaction to the impending loss of its hegemony over knowledge, conducted a series of important observations with a new instrument, the telescope. His work confirmed and built upon that of his contemporaries and predecessors._^<g_In 1687, Sir Isaac _^<a!T23573_Newton_^>a_ published "Mathematical Principles of Natural Philosophy" and became the culminating figure of the scientific revolution. He described a series of physical laws on inertia and acceleration. His third law ascribed to every action an equal and opposite reaction. Newton's law of _^<a!T14264_gravitation_^>a_ is perhaps his most famous._^<g_Scientists also looked inward during this period, and discoveries were many. In 1543, Andreas _^<a!T33919_Vesalius_^>a_ published _^<i_On the Structure of the Human Body_^>i_, which provided a detailed account of human _^<a!T1232_anatomy_^>a_ based on Vesalius' dissections. Eighty-five years later, William _^<a!T15199_Harvey_^>a_ published his work on _^<a!T3984_blood_^>a_ circulation and introduced quantitative reasoning to _^<a!T3711_biology_^>a_. By the middle of the 17th century, the invention of the _^<a!T21889_microscope_^>a_ triggered enormous strides in the development of knowledge about anatomy. In 1661, Marcello _^<a!T20818_Malpighi_^>a_ first saw the capillaries._^<g_In addition to the empirical information gathered by the new sciences, methodology to secure the veracity of these findings took form. The invention of _^<a!T26581_printing_^>a_ in the 15th century allowed for the widespread distribution of theories that could be independently tested by others, however far removed from the site of the original work. National scientific societies were established to organize the work and provide a formal setting for the exchange of ideas and information. In 1637, Rene _^<a!T9454_Descartes_^>a_ published his _^<i_Discourse on Method_^>i_ and proposed that certainty can only be found after an exhaustive accumulation of evidence. Francis Bacon, too, developed the methodology of inductive science, which had wide-ranging influence._^<g_See also: _^<a!T2081_astronomy, history of_^>a_; _^<a!T2465_Bacon, Francis (philosopher)_^>a_; _^<a!T15459_heliocentric world system_^>a_; _^<a!T18245_Kepler's laws_^>a_; _^<a!T19343_Leeuwenhoek, Antoni van_^>a_; _^<a!T24083_observatory, astronomical_^>a_; _^<a!T25967_planets and planetary systems_^>a_; _^<a!T29134_science, history of_^>a_; _^<a!T32021_telescope, optical_^>a__^<g_
A dramatic increase in the flow of Protestant German immigrants to the United States began in 1709 and within a short time swelled the population of the Middle Colonies and the back-country south by 250,000. The immigrants were primarily members of the Lutheran and German Reformed (Calvinist) churches._^<g_See also: _^<a!T5533_Calvinism_^>a_; _^<a!T16738_immigration_^>a_; _^<a!T20290_Lutheranism_^>a_; _^<a!T33462_United States, history of the_^>a__^<g_
Legendary American frontiersman Daniel _^<a!T4260_Boone_^>a_ gained his first measure of prominence in 1755 as a teamster and blacksmith on an expedition to Fort Duquesne led by Gen. George Braddock. During the expedition, Boone escaped the assault by French and Indian forces._^<g_See also: _^<a!T35019_Wilderness Road_^>a_._^<g_
The _^<a!T9246_Declaration of Independence_^>a_ is the statement of principles that led the _^<a!T8005_Continental Congress_^>a_ to vote for the political separation of the American colonies from Great Britain on July 4, 1776. The document, arguably the most famous in U.S. history, was written largely by _^<a!T17488_Thomas Jefferson_^>a_._^<g_
The armed rebellion of American colonists against Great Britain began in 1775 and ended eight years later with the Treaty of Paris and American independence. The decisive battle was General George _^<a!T34496_Washington_^>a_'s 1781 victory over Lord Cornwallis at Yorktown._^<g_See also: _^<a!T1106_American Revolution_^>a_._^<g_
The slave trade enveloped western Africa between the 16th and 19th centuries. In the 18th century alone, an estimated 6 million Africans were placed on ships and taken to the North American colonies. Thousands died during the Middle Passage across the Atlantic Ocean._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T30103_slavery_^>a_._^<g_
In 1777, Vermont's constitution abolished _^<a!T30103_slavery_^>a_, thereby initiating a wave of antislavery laws in the northern _^<a!T33459_United States_^>a_. Slavery was legal in the southern states until the end of the U.S. Civil War in 1865. Antislavery societies were founded in England (1787) and in France (1788)._^<g_See also: _^<a!T81_abolitionists_^>a_; _^<a!T402_African Americans_^>a_._^<g_
Englishman Abraham Darby made a fundamental contribution to early industrialization when he fashioned (1709) a coke-smelting process. The process, which used fewer raw materials than the traditional charcoal- or coal-fired furnaces, eventually revolutionized the iron industry._^<g_See also: _^<a!T8964_Darby (family)_^>a_; _^<a!T31982_technology, history of_^>a_._^<g_
Scottish engineer James _^<a!T34586_Watt_^>a_ developed and patented a separate condenser chamber for the steam engine in 1769. Although Thomas _^<a!T23545_Newcomen_^>a_ invented the steam engine years earlier, Watt's improvements catalyzed the device's widespread use in the _^<a!T16861_Industrial Revolution_^>a_._^<g_See also: _^<a!T30923_steam engine_^>a_; _^<a!T31982_technology, history of_^>a_._^<g_
In 1793, Eli _^<a!T34943_Whitney_^>a_ invented a machine that separated cotton seeds from the fiber. The introduction of the _^<a!T8277_cotton gin_^>a_ revolutionized the _^<a!T32186_textile industry_^>a_ but revived slavery in cotton-growing areas of North America. Whitney's cotton gin did not bring him wealth, however, as the design was imitated by others._^<g_See also: _^<a!T486_agriculture, history of_^>a_._^<g_
Catherine II, Empress of Russia, or Catherine the Great, ruled Russia between 1762 and 1796 after seizing power following a coup that toppled her husband, Peter II. Catherine II continued Peter I's transformation of Russia into a modern country, expanded the empire and withstood a revolt in the east._^<g_See also: _^<a!T6186_Catherine II, Empress of Russia (Catherine the Great)_^>a_; _^<a!T28301_Russo-Turkish Wars_^>a_._^<g_
The War of the Spanish Succession, the longest and bloodiest war of French King _^<a!T20098_Louis XIV_^>a_, was contested throughout the Spanish Empire from 1701 to 1714 and ended with Britain atop a vast colonial and naval empire. The war erupted after the last Spanish Hapsburg king, Charles II, died childless. European powers then launched the struggle to fill the power vacuum._^<g_See also: _^<a!T6617_Charles II, King of Spain_^>a_; _^<a!T30577_Spanish Succession, War of the_^>a_._^<g_
The Scottish philosopher and economist Adam Smith formulated his theory of how economies work in one of the most influential studies ever of Western civilization, _^<i_An Inquiry into the Nature and Causes of the Wealth of Nations_^>i_, published in 1776_^<g_
St. Andrew's Church was constructed between 1747 and 1753 at the command of Peter the Great's daughter, Elizaveta. The Baroque-style church was built on Andreevsky Hill, the highest point of Old Kiev, and its interior reflects the period's widespread use of screens decorated with images of Jesus Christ to separate the sanctuary from the rest of the church._^<g_See also: _^<a!T2827_baroque art and architecture_^>a_._^<g_
The _^<a!T29492_Seven Years' War_^>a_ was one of the first worldwide conflicts. It pitted Britain and Prussia against Austria, France, Russia, Saxony, Sweden and Spain over a variety of territorial issues over two hemispheres. The fighting began in 1756 when Frederick II of Prussia (who eventually emerged victorious in 1763) attacked an Austrian ally, Saxony._^<g_See also: _^<a!T11397_Europe, history of_^>a_; _^<a!T12725_French and Indian Wars_^>a__^<g_
The French Revolution took place in many phases, with the first three occurring between 1789 and 1799. Over that period, revolutionists spurred by political crisis on the throne and economic collapse uprooted France's monarchal past and moved the country toward modern nationhood._^<g_See also: _^<a!T2949_Bastille_^>a_; _^<a!T11397_Europe, history of_^>a_; _^<a!T12625_France, history of_^>a_._^<g_
The foundations for the initial vast French Empire in West Africa were established by various expeditions between the years of 1714 and 1720. By the early-20th century, the French had assembled a second African empire that totaled 10,000,000 sq km (4,000,000 sq mi) and 60 million people._^<g_See also: _^<a!T12792_French colonial empire_^>a_; _^<a!T12809_French West Africa_^>a_._^<g_
Wolfgang Amadeus _^<a!T22740_Mozart_^>a_ is widely considered to be the greatest musical genius who ever lived. Born in Austria in 1756, Mozart reached his greatest success in 1786 with _^<i_The Marriage of Figaro_^>i_ which was composed for the Vienna Opera. Mozart composed piano concertos and string quartets in addition to opera._^<g_See also: _^<a!T7282_classical period in music_^>a_; _^<a!T22918_music_^>a_._^<g_
The Hawa Mahal of Jaipur, India, was built as part of the city plan developed by its founder, Maharaja Sawaii Jai Singh II, in 1727. The Hawa Mahal is a five-story building renowned for its sculptured look and harmony of context with the rest of the city. _^<i_Hawa Mahal_^>i_ means "Hall of Winds."_^<g_See also: _^<a!T1713_architecture_^>a_; _^<a!T16803_Indian art and architecture_^>a_._^<g_
_^<a!T23021_Nadir Shah_^>a_ ruled (1736-47) Iran's Afshar dynasty and became known as one of the great Asian conquerors. As a military leader in the early 1730s, Nadir Shah ejected the Afghan rulers who sparked the end of the Safavid dynasty. He was assassinated by religious and army leaders in June, 1747._^<g_See also: _^<a!T17103_Iran_^>a_. _^<g_
The leader of a Sikh kingdom from 1780, Ranjit Singh ruled a large section of northwest India after ending the persecution of _^<a!T29866_Sikhs_^>a_ by the Muslim Mogul rulers. After Singh died (1839), however, the kingdom collapsed, and the British moved into the Punjab, triggering the Sikh wars of 1845-46 and 1848-49._^<g_See also: _^<a!T1995_Asia, history of_^>a_; _^<a!T26858_Punjab_^>a_._^<g_
Benjamin _^<a!T12674_Franklin_^>a_ made many contributions to the diplomatic, philosophical and inventive arts, but his most enduring legacy may be his work on electricity. In 1752, Franklin attached a key to a kite string, flew the kite, and established that lightning was a form of electricity. This famous experiment led to the invention of the lightning rod. His other famous achievements include the Franklin stove._^<g_See also: _^<a!T10792_electricity_^>a_; _^<a!T26257_Poor Richard's Almanack_^>a_._^<g_
On April 30, 1803, the United States purchased the _^<a!T20111_Louisiana_^>a_ Territory from France for about $15 million. The _^<a!T20113_Louisiana Purchase_^>a_ enlarged U.S. territory by more than 2 million sq km (800,00 sq mi) of land, extending the nation's frontiers from the Mississippi River to the Rocky Mountains._^<g_See also: _^<a!T11533_exploration_^>a_; _^<a!T17488_Jefferson, Thomas_^>a_; _^<a!T33462_United States, history of the_^>a_._^<g_
After five months of war with _^<a!T21816_Mexico_^>a_, Anglo-American colonists in _^<a!T32181_Texas_^>a_ called a convention in March, 1836, and issued a declaration of independence. A decisive victory over Mexican troops in October 1836 secured the republic's independence. Texas was annexed by the _^<a!T33459_United States_^>a_ in 1845._^<g_See also: _^<a!T619_Alamo_^>a_; _^<a!T2256_Austin, Stephen F._^>a_; _^<a!T16237_Houston, Sam_^>a_; _^<a!T32185_Texas Revolution_^>a_._^<g_
The discovery of _^<a!T13916_gold_^>a_ at Sutter's Mill in California in 1848 ignited the greatest gold rush in American history. At first, only residents from nearby San Francisco and other parts of California took part but, by 1849, the rush became globalized, and the expression "Forty-niners" emerged as part of an enduring chapter of U.S. history._^<g_See also: _^<a!T31493_Sutter, John Augustus_^>a_._^<g_
The _^<a!T7213_U.S. Civil War_^>a_ erupted in 1861 and when it was over four years later the country was changed forever. The industrialized North overwhelmed the agrarian, rebellious South and in the process forged a world power. Slavery was crushed, and other vast social and economic changes were set in motion by the conflict._^<g_See also: _^<a!T402_African Americans_^>a_; _^<a!T7861_Confederate States of America_^>a_; _^<a!T19734_Lincoln, Abraham_^>a_._^<g_
Beginning with the _^<a!T17409_Jamestown_^>a_ settlement of 1607, settlers swarmed across the midsection of the North American continent and incrementally extended the frontier westward until around 1890. By the last decade of the 19th century, the frontier line had effectively disappeared, as settlers had exhausted any new land for homesteaders._^<g_See also: _^<a!T16031_Homestead Act_^>a_; _^<a!T33208_Turner, Frederick Jackson_^>a_; _^<a!T33462_United States, history of the_^>a_._^<g_
Nat _^<a!T33214_Turner_^>a_ led a slave insurrection in Southhampton County, Va., on August 21, 1831. Believing that he was acting under a signal from a vengeful God to free slaves, Turner recruited about 70 slaves to take part and launched the rebellion, which ended in the deaths of at least 57 whites. Turner was later captured and executed._^<g_See also: _^<a!T402_African Americans_^>a_; _^<a!T7213_Civil War, U.S._^>a_. _^<g_
A popular book on the injustices of slavery, _^<i__^<a!T33396_Uncle Tom's Cabin_^>a__^>i_, enhanced the abolitionist movement in mid-19th-century America. Author Harriet Beecher _^<a!T31147_Stowe_^>a_ first published _^<i_Uncle Tom's Cabin_^>i_ in serial form, from 1851 to 1852, and some blamed its popularity for starting the U.S. _^<a!T7213_Civil War_^>a_._^<g_See also: _^<a!T81_abolitionists_^>a_; _^<a!T1094_American literature_^>a_._^<g_
In a decision that heightened rising sectional tensions over _^<a!T30103_slavery_^>a_, the _^<a!T31447_Supreme Court of the United States_^>a_ ruled in 1857 that a slave could not become a U.S. citizen. The _^<i__^<a!T10142_Dred Scott v. Sandford_^>a__^>i_ decision stemmed from a lawsuit filed by Dred Scott, who contended that he was free because he resided in a free territory._^<g_See also: _^<a!T402_African Americans_^>a_; _^<a!T7213_Civil War, U.S._^>a_; _^<a!T31771_Taney, Roger B._^>a_._^<g_
President Abraham Lincoln issued the largely symbolic _^<a!T10936_Emancipation Proclamation_^>a_ during the war to end slavery in the United States. The proclamation, issued January 1, 1863, freed all slaves residing in territory in rebellion against the federal government._^<g_See also: _^<a!T7213_Civil War, U.S._^>a_; _^<a!T19734_Lincoln, Abraham_^>a_; _^<a!T30103_slavery_^>a_; _^<a!T32312_Thirteenth Amendment_^>a_._^<g_
In 1896, Homer Plessy of Louisiana asked the U.S. Supreme Court to overturn a state law that required separate accommodations for white and "colored" railroad passengers. The court ruled against Plessy, holding that separate but equal accommodations were constitutional._^<g_See also: _^<a!T12582_Fourteenth Amendment_^>a_; _^<a!T17586_Jim Crow laws_^>a_; _^<i__^<a!T26031_Plessy v. Ferguson_^>a__^>i_; _^<a!T31447_Supreme Court of the United States_^>a_._^<g_
The _^<i__^<a!T7342_Clermont_^>a__^>i_, a steamboat designed by Robert Fulton, made its first voyage on Aug. 9, 1807, from New York Harbor to Albany. The 240-km (150-mi) trip started a profitable service and ushered in the age of steam-powered water transportation for passengers and cargo._^<g_See also: _^<a!T12127_Fitch, John_^>a_; _^<a!T12962_Fulton, Robert_^>a_._^<g_
British naturalist Charles Darwin formulated the theory of _^<a!T11480_evolution_^>a_ when he served as a naturalist on the 1831-36 scientific voyage of the H.M.S. _^<i_Beagle_^>i_. In 1859, he published _^<i_Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life_^>i_. It presented his idea that species evolve from more primitive species through the process of _^<a!T23253_natural selection_^>a_._^<g_See also: _^<a!T8997_Darwin, Charles_^>a_; _^<a!T13401_genetics_^>a_; _^<a!T34348_Wallace, Alfred Russel_^>a_._^<g_
Seven years after he first showed that long-distance telegraphy was possible, Samuel F. B. Morse successfully demonstrated (1844) his magnetic _^<a!T32012_telegraph_^>a_ between Baltimore and Washington. It ushered in the age of long-distance telegraph transmission._^<g_See also: _^<a!T22611_Morse, Samuel F. B._^>a_; _^<a!T31982_technology, history of_^>a_._^<g_
On Aug. 27, 1859, in Titusville, Penn., Edwin Laurentine Drake drilled the first successful oil well in the United States. Using techniques borrowed from the drilling of salt wells, Drake struck oil after months of unsuccessful attempts. The well produced 25 barrels of crude oil per day and ignited a massive oil rush in Pennsylvania._^<g_See also: _^<a!T10171_drilling_^>a_; _^<a!T25344_Pennsylvania_^>a_; _^<a!T25570_petroleum_^>a_._^<g_
Alexander Graham Bell, a speech teacher for deaf students in Boston, Mass., patented the _^<a!T32020_telephone_^>a_ in 1876. Bell's telephone evolved from research he was conducting on methods to place more messages into a single telegraph line. Bell realized that if more frequencies could be transmitted over a line, so could the human voice._^<g_See also: _^<a!T3245_Bell, Alexander Graham_^>a_; _^<a!T31982_technology, history of_^>a_; _^<a!T32009_telecommunications_^>a_._^<g_
Thomas Alva _^<a!T10627_Edison_^>a_ developed the first commercially practical _^<a!T16774_incandescent lamp_^>a_, or lightbulb, in 1879. His laboratory, in Menlo Park, N.J., churned out a variety of other inventions, including the _^<a!T25703_phonograph_^>a_, flexible celluloid film and the motion-picture _^<a!T26638_projector_^>a_._^<g_See also: _^<a!T12011_film, history of_^>a_; _^<a!T31982_technology, history of_^>a_._^<g_
Written by Karl _^<a!T21186_Marx_^>a_ in association with Friedrich _^<a!T11030_Engels_^>a_ in 1848, the _^<i__^<a!T7747_Communist Manifesto_^>a__^>i_ is one of the fundamental documents of _^<a!T21188_Marxism_^>a_ and modern Communism. The brief work outlines Marx's interpretation of history as one marked by constant struggle among economic classes._^<g_See also: _^<a!T7745_communism_^>a_; _^<i__^<a!T18049_Kapital, Das_^>a__^>i_; _^<a!T30303_socialism_^>a_; _^<a!T30885_state (in political philosophy)_^>a_._^<g_
On Feb. 19, 1861, _^<a!T765_Alexander II, Emperor of Russia_^>a_ abolished serfdom, making 20 million peasants their own masters. The former serfs, however, remained second-class citizens, were charged for the allotments of land they received at emancipation, and were denied full access to regular courts._^<g_See also: _^<a!T11397_Europe, history of_^>a_; _^<a!T20931_manorialism_^>a_; _^<a!T28285_Russia, history of_^>a_._^<g_
War between Russia and Turkey erupted in 1877 after Turkish repression of nationalist agitation in the _^<a!T2602_Balkans_^>a_ triggered a Russian response. In 1878 Russia won and forced Turkey to sign the Treaty of San Stefano, which gave the victors extensive rights and territories and underscored the decline of the _^<a!T24626_Ottoman Empire_^>a_._^<g_See also: _^<a!T3464_Berlin, Congress of_^>a_; _^<a!T28285_Russia, history of_^>a_; _^<a!T33189_Turkey_^>a_._^<g_
_^<a!T23090_Napoleon I, Emperor of the French_^>a_, commanded the French Revolutionary armies in the late-18th century as Napoleon Bonaparte and seized political power in 1799. In 1804, he proclaimed himself Emperor Napoleon I and stretched French rule over vast tracts of Europe before he was finally defeated (1814-15)._^<g_See also: _^<a!T4194_Bonaparte (family)_^>a_; _^<a!T12805_French Revolution_^>a_; _^<a!T23093_Napoleonic Wars_^>a_. _^<g_
Fought outside of Brussels on June 18, 1815, the Battle of Waterloo closed the curtain on the career of _^<a!T23090_Napoleon I_^>a_, whose outnumbered army was smashed by the combined forces of the Duke of Wellington's Anglo-German-Dutch squads and the Prussian army of Gebhard Leberecht von _^<a!T4022_Blucher_^>a_._^<g_See also: _^<a!T34564_Waterloo, Battle of_^>a_; _^<a!T34738_Wellington, Arthur Wellesley, 1st Duke of_^>a_._^<g_
A systemic infection of potatoes in _^<a!T17110_Ireland_^>a_ triggered a massive _^<a!T11675_famine_^>a_ that depopulated the countryside. Ireland's population reached 8.1 million in 1841, but the famine generated deaths and emigration on such a scale that the country's population was sliced in half by the early-20th century._^<g_See also: _^<a!T9775_diseases, plant_^>a_; _^<a!T17111_Ireland, history of_^>a_; _^<a!T26279_population dynamics_^>a_._^<g_
Florence _^<a!T23662_Nightingale_^>a_, the first woman to receive the British Order of Merit, is widely considered to be the founder of modern _^<a!T24008_nursing_^>a_. As supervisor of British army hospitals during the _^<a!T8492_Crimean War_^>a_ (1853-56), she revolutionized army medical care and constructed strict sanitary and nursing standards._^<g_
The _^<a!T8492_Crimean War_^>a_ (1853-56) was one of several 19th-century conflicts between _^<a!T28284_Russia_^>a_ and the Turkey-based _^<a!T24626_Ottoman Empire_^>a_, but the involvement of British and French against Russia altered the outcome. The fall of Sevastopol in 1855 forced Russia to yield to stiff peace demands incorporated in the 1856 Treaty of Paris._^<g_See also: _^<a!T6578_Charge of the Light Brigade, The_^>a_; _^<a!T8490_Crimea_^>a_; _^<a!T28301_Russo-Turkish Wars_^>a_._^<g_
The _^<a!T31329_Suez Canal_^>a_ opened in 1869, after 15 years of planning and construction under the supervision of Ferdinand de Lesseps, a French diplomat. The canal crossed the Isthmus of Suez. It allows vessels to travel between the eastern part of the Mediterranean Sea and the Indian Ocean through the Gulf of Suez and the Red Sea._^<g_See also: _^<a!T19502_Lesseps, Ferdinand Marie, Vicomte de_^>a_; _^<a!T26305_Port Said_^>a_; _^<a!T31330_Suez Crisis_^>a_._^<g_
The _^<a!T24412_Opium Wars_^>a_ of 1839-42 and 1856-60 marked the first major military clashes between _^<a!T6872_China_^>a_ and the West. China lost both. For the defeated Chinese, the wars ended their isolation while starting a century of humiliation by foreign powers. Chinese objections to opium imports by British merchants triggered the conflicts._^<g_See also: _^<a!T16063_Hong Kong_^>a_; _^<a!T24411_opium_^>a_; _^<a!T26944_Qing_^>a_._^<g_
American naval officer Matthew Calbraith _^<a!T25475_Perry_^>a_ led a mission to Japan to negotiate a treaty to protect shipwrecked American seamen and expand U.S. commerce. In 1854, _^<a!T17427_Japan_^>a_ agreed to care for stranded American sailors and to open ports to American merchants. That began the drive to end Japan's long isolation._^<g_See also: _^<a!T17428_Japan, history of_^>a_._^<g_
The collapse of Japan's Tokugawa shogunate in 1867 opened the way for the country's formal reentry into the world a year later under Emperor Meiji. For two centuries, _^<a!T17427_Japan_^>a_ had followed a policy of seclusion, which cut it off from the world and delayed its development into an industrialized state._^<g_See also: _^<a!T21539_Meiji Restoration_^>a_; _^<a!T29751_shogun_^>a_; _^<a!T32644_Tokugawa (family)_^>a_._^<g_
The rapid industrialization of _^<a!T17427_Japan_^>a_ following the end of its isolation emerged in the Sino-Japanese War of 1894-95. Japan showed its clear military superiority over _^<a!T6872_China_^>a_ and seized control of _^<a!T18610_Korea_^>a_. The victory secured Japan's place as an industrialized power at the end of the 19th century._^<g_See also: _^<a!T6873_China, history of_^>a_; _^<a!T17428_Japan, history of_^>a_; _^<a!T29986_Sino-Japanese Wars_^>a_._^<g_
When the _^<a!T24877_Panama Canal_^>a_ was completed in 1914, many observers acknowledged it as the greatest engineering feat of the modern age. Construction on the canal began in 1904. It took workers ten years to cut through the Isthmus of Panama in Central America and build the lock system._^<g_See also: _^<a!T7305_Clayton-Bulwer Treaty_^>a_; _^<a!T15285_Hay-Pauncefote Treaty_^>a_; _^<a!T24878_Panama Canal Zone_^>a_._^<g_
In 1920, the 18th Amendment to the U.S. Constitution brought the era of _^<a!T26633_prohibition_^>a_. The amendment, which barred the manufacture, sale, and transport of alcoholic beverages, was annulled in 1933 by the 21st Amendment. National prohibition was the product of a century-long reform movement._^<g_See also: _^<a!T4272_bootlegging_^>a_; _^<a!T10709_Eighteenth Amendment_^>a_; _^<a!T32050_temperance movement_^>a_; _^<a!T33261_Twenty-First Amendment_^>a_._^<g_
Herbert Clark Hoover became the 31st president of the United States in 1929, within months of the onset of a global economic depression. Hoover, a Republican, sought to contain the economic collapse mainly through pleas of voluntarism to help the needy, but the depression deepened and he was swept out of office by Franklin Delano Roosevelt._^<g_See also: _^<a!T9422_Depression of the 1930s_^>a_; _^<a!T16097_Hoover, Herbert_^>a_; _^<a!T28032_Roosevelt, Franklin Delano_^>a_._^<g_
Known as the Great Depression because of its magnitude and consequences, a severe economic crisis roiled Western capitalism in the 1930s. In 1933, unemployment rates around the world varied between 15 percent and 25 percent. Only massive government spending for _^<a!T35397_World War II_^>a_ ended the crisis in the U.S._^<g_See also: _^<a!T9422_Depression of the 1930s_^>a_; _^<a!T33462_United States, history of the_^>a_._^<g_
The _^<a!T23467_New Deal_^>a_, a term first used by President Franklin Delano _^<a!T28032_Roosevelt_^>a_ in his 1933 inaugural address, was a collection of federal-government programs to provide relief to the needy and to promote economic reforms during the _^<a!T9422_Depression of the 1930s_^>a_. The _^<a!T35379_Works Progress Administration_^>a_, initiated in 1935 as part of the New Deal, created eight million jobs to build public facilities and create works of art._^<g_
W. E. B. Du Bois, the most influential spokesman for black-American civil rights from the late-19th century, wrote _^<i_The Souls of Black Folk_^>i_ (1903), a part-autobiographical account of the black experience in the United States. Du Bois was later editor of _^<i_The Crisis,_^>i_ a periodical published by _^<a!T23158_National Association for the Advancement of Colored People_^>a_._^<g_See also: _^<a!T402_African Americans_^>a_; _^<a!T10218_Du Bois, W. E. B._^>a_; _^<a!T16969_integration, racial_^>a_._^<g_
The _^<a!T18714_Ku Klux Klan_^>a_ was revived in the 1920s after a long period of inactivity. The Klan, which had more than two million adherents at the height of its popularity in the 1920s, often adopted vigilante tactics to underscore its anti-Catholic, anti-Jewish, anti-black message. Its appeal began to fade in the 1930s._^<g_See also: _^<a!T402_African Americans_^>a_; _^<a!T27100_radicalism_^>a_; _^<a!T27348_Reconstruction_^>a_._^<g_
The 19th Amendment to the _^<a!T7979_Constitution of the United States_^>a_, approved by Congress in 1918, gave women the right to vote when ratification by the states was completed in August, 1920. This ended a 72-year formal effort for women's suffrage which began at the _^<a!T29388_Seneca Falls Convention_^>a_ of 1848._^<g_See also: _^<a!T23695_Nineteenth Amendment_^>a_; _^<a!T31336_suffrage, women's_^>a_; _^<a!T35296_women in society_^>a_. _^<g_
Congress enacted the _^<a!T16812_Indian Reorganization Act_^>a_ in 1934 in response to growing criticism over the treatment of _^<a!T16824_American Indians_^>a_ on federal reservations. The act forbade the further allotment of tribal lands to individual Indians and authorized the purchase of additional lands for Indians._^<g_See also: _^<a!T9091_Dawes Act_^>a_._^<g_
Eleanor _^<a!T28031_Roosevelt_^>a_ was appointed a member of the United States delegation to the _^<a!T33451_United Nations_^>a_ by President Harry S. Truman in December 1945. Roosevelt, the wife of President Franklin D. Roosevelt, chaired the UN Commission on Human Rights and was instrumental in drafting its Universal Declaration on Human Rights (1948)._^<g_See also: _^<a!T16376_human rights_^>a_._^<g_
The science and practice of aviation began in North Carolina on Dec. 17, 1903, when _^<a!T35439_Orville Wright_^>a_ made the first successful powered flight. Orville and his brother _^<a!T35439_Wilbur_^>a_, bicycle manufacturers from Ohio, designed and built the aircraft. They selected an isolated area in Kitty Hawk, North Carolina to test it._^<g_See also: _^<a!T17063_invention_^>a_; _^<a!T26659_propeller_^>a_._^<g_
_^<a!T2301_Automobile_^>a_ manufacturer Henry _^<a!T12419_Ford_^>a_ greatly enhanced mass-production techniques when he completed (1913) the development of the moving _^<a!T2034_assembly line_^>a_. By 1914, the line was used to assemble entire automobiles, saving significant amounts of time and labor and reducing the cost of the automobile._^<g_See also: _^<a!T2303_automotive industry_^>a_; _^<a!T22227_Model T_^>a_._^<g_
Breakthroughs in _^<a!T32025_television_^>a_ broadcasting occurred (1935-36) when British, French and American engineers enhanced the clarity of television images, and regular television service was begun in London. In the United States, the Radio Corporation of America began field tests of its television system in New York._^<g_See also: _^<a!T27108_radio and television broadcasting_^>a_; _^<a!T32026_television production_^>a_; _^<a!T35935_Zworykin, Vladimir Kosma_^>a_._^<g_
In 1929, Scottish biologist _^<a!T12224_Alexander Fleming_^>a_ first observed the effects of penicillin on bacteria. Fleming, however, neither purified the drug nor established its effectiveness in treating bacterial infections. A separate group of biologists did that in 1941._^<g_See also: _^<a!T1475_antibiotics_^>a_; _^<a!T12263_Florey, Sir Howard Walter_^>a_._^<g_
The consolidation of Russian political power by the Bolsheviks in November 1917 occurred amid social upheaval throughout Russia. Throughout 1917, peasants revolted against wealthy landowners and seized their land and fields. All the while their traditional social patterns and values were unraveling under the forces of industrialization and World War I. The Bolsheviks sought to exploit the upheaval and build a classless society on the ruins of the Revolutions of 1917._^<g_See also: _^<a!T7745_communism_^>a_; _^<a!T19424_Lenin, Vladimir Ilich_^>a_; _^<a!T28296_Russian Revolutions of 1917_^>a_._^<g_
Joseph _^<a!T30818_Stalin_^>a_ used his position as general secretary of the Communist party's central committee to control political developments in the Soviet Union after the death (1924) of Vladimir I. Lenin. It took him five years to consolidate power and end opposition to his rule. From 1929 until his death in 1953, Stalin ruled with absolute authority and headed one of the most ruthless regimes in history._^<g_See also: _^<a!T14310_Great Purge_^>a_; _^<a!T18735_kulaks_^>a_; _^<a!T33435_Union of Soviet Socialist Republics_^>a_._^<g_
The collapse of the Ottoman Empire's Balkan territories ignited the Balkan Wars of 1912-13. Tsarist Russia, Greece, and Montenegro allied with Bulgaria and Serbia in 1911 to form the Balkan League. In 1912, the Balkan allies scored quick military victories and defeated the empire._^<g_See also: _^<a!T2602_Balkans_^>a_; _^<a!T24626_Ottoman Empire_^>a_._^<g_
The _^<a!T19278_League of Nations_^>a_, formed to promote international peace at the _^<a!T24993_Paris Peace Conference_^>a_ in 1919, came into being on Jan. 10, 1920. Sixty-three nations signed the charter, but one of the principal organizers, the United States, did not. An important diplomatic instrument in the 1920s, the League gradually lost members and was succeeded by the _^<a!T33451_United Nations_^>a_ in 1946._^<g_See also: _^<a!T20874_mandate system_^>a_; _^<a!T35140_Wilson, Woodrow_^>a_; _^<a!T35394_World War I_^>a__^<g_
Benito _^<a!T22948_Mussolini_^>a_ was the Fascist dictator of Italy from 1925 to 1943. He secured power after _^<a!T33960_King Victor Emmanuel III_^>a_ asked him to form a coalition government during a period of anarchy in Italy. Mussolini's aggressive foreign policy led to the conquest of _^<a!T11325_Ethiopia_^>a_ in 1936 and to the alliance with Nazi Germany in 1939. Mussolini fell from power in 1943 and was shot and killed by Italian partisans in April 1945._^<g_See also: _^<a!T1226_anarchism_^>a_; _^<a!T11735_fascism_^>a_; _^<a!T17254_Italy, history of_^>a_; _^<a!T19137_Lateran Treaty_^>a_; _^<a!T23290_Nazism_^>a_._^<g_
A military uprising led by Gen. Francisco _^<a!T12649_Franco_^>a_ in 1936 triggered the _^<a!T30567_Spanish Civil War_^>a_, a conflict that ended in 1939 with the defeat of the Spanish republic. Within a year of the start of hostilities between Loyalists and Nationalists, the fighting turned into a stalemate._^<g_See also: _^<a!T11735_fascism_^>a_; _^<a!T30558_Spain, history of_^>a_._^<g_
The Yihe Quang (I-ho Ch'uan, or "righteous harmony fists") sought to expel foreigners and foreign influence from _^<a!T6872_China_^>a_ between 1898 and 1900. Foreigners and Christian Chinese were killed in the _^<a!T4486_Boxer Uprising_^>a_ (also known as the Boxer Rebellion). An international force suppressed the attacks in 1900._^<g_See also: _^<a!T6873_China, history of_^>a_; _^<a!T7218_Cixi, Dowager Empress of China (Tz'u-hsi)_^>a__^<g_
The last imperial dynasty in _^<a!T6872_China_^>a_ was overthrown in 1911. The _^<a!T26944_Qing_^>a_ (Manchu) dynasty, founded by Manchurian conquerors in 1644, collapsed when a movement arose to make China a republic. The Chinese empire had reached its greatest geographical extent under the Manchus._^<g_See also: _^<a!T6873_China, history of_^>a_; _^<a!T31401_Sun Yat-sen_^>a__^<g_
Often referred to as "the Great War," _^<a!T35394_World War I_^>a_ involved all the great powers of Europe and eventually most countries of the world between 1914 and 1918. The causes of the war included rising nationalist sentiment, colonial rivalries, hostile alliances, and arms races. More than 8 million soldiers were killed._^<g_See also: _^<a!T11397_Europe, history of_^>a_; _^<a!T31175_strategy and tactics, military_^>a_; _^<a!T33868_Verdun_^>a_._^<g_
In 1921, Irish and British officials signed a treaty making the Irish Free State a self-governing dominion and allowing Northern Ireland's Parliament to keep six northern counties out of the dominion. The treaty sparked a civil war in the south. Protreaty forces won, and framed a constitution in 1922._^<g_See also: _^<a!T17111_Ireland, history of_^>a_; _^<a!T17133_Irish Republican Army_^>a_; _^<a!T23873_Northern Ireland_^>a_._^<g_
_^<a!T15873_Adolf Hitler_^>a_ seized full political power in Germany in 1933. By 1939, he had ignited _^<a!T35397_World War II_^>a_ and initiated his policy of exterminating Jews from Germany and other European countries. About 6 million Jews were killed under Hitler's policy. Tens of millions of soldiers and civilians were killed as a result of the battles that raged through Europe. Hitler committed suicide (1945) during the closing days of the war._^<g_See also: _^<a!T13522_Germany, history of_^>a_; _^<a!T15992_Holocaust_^>a_; _^<a!T23290_Nazism_^>a_._^<g_
In the twelve years following the death (1916) of Chinese Republic leader _^<a!T35719_Yuan Shikai_^>a_, rival groups including several warlords contended for power in _^<a!T6872_China_^>a_. The power struggle ultimately focused on the rift between nationalists and communists. By 1928, nationalists under _^<a!T6795_Chiang Kai-shek_^>a_ had nominally reunited China._^<g_See also: _^<a!T20966_Mao Zedong (Mao Tse-tung)_^>a_._^<g_
One of the most epic marches ever, the 1934-35 _^<a!T19986_Long March_^>a_ headed by Chinese communist leader _^<a!T20966_Mao Zedong (Mao Tse-tung)_^>a_ was a 10,000-km (6,000-mi) journey across _^<a!T6872_China_^>a_. The march began when nationalist troops sought to eliminate the communist threat to their power over China._^<g_See also: _^<a!T6873_China, history of_^>a_; _^<a!T35840_Zhou Enlai (Chou En-lai)_^>a_._^<g_
Fought from 1904 to 1905, the _^<a!T28300_Russo-Japanese War_^>a_ marked the first modern conflict in which an Asian power emerged victorious over a European country. Conflicting ambitions to control _^<a!T20865_Manchuria_^>a_ and Korea ignited the conflict, in which the Russian fleet was obliterated in the Battle of Tsushima._^<g_See also: _^<a!T1995_Asia, history of_^>a_; _^<a!T18610_Korea, history of_^>a_; _^<a!T33104_Tsushima, Battle of_^>a__^<g_
A staged bombing of the Japanese-controlled South Manchuria Railroad served as the pretext for Japan's 1931 occupation of _^<a!T20865_Manchuria_^>a_. The attack was carried out by military officers without authorization from the political leaders of _^<a!T17427_Japan_^>a_. The country, formally established in 1932, was renamed _^<a!T20864_Manchukuo_^>a_._^<g_See also: _^<a!T29674_Shenyang (Shen-yang)_^>a_; _^<a!T29986_Sino-Japanese Wars_^>a_._^<g_
Beginning with the annexation of _^<a!T20865_Manchuria_^>a_ in 1931-32 and the seizure of several Chinese cities in 1937, _^<a!T17427_Japan_^>a_ sought to establish economic hegemony over East Asia. That strategy ultimately led to the expansion of _^<a!T35397_World War II_^>a_ throughout the Pacific region. Japan surrendered in August 1945._^<g_See also: _^<a!T2356_Axis (alliance)_^>a_; _^<a!T8109_Coral Sea_^>a_; _^<a!T17428_Japan, history of_^>a_._^<g_
The _^<a!T33459_United States_^>a_ entered _^<a!T35397_World War II_^>a_ after Japanese warplanes attacked the U.S. naval base in _^<a!T25220_Pearl Harbor_^>a_, Hawaii, on Dec. 7, 1941. The attack, carried out by hundreds of planes flying from aircraft carriers, killed 2,400 Americans, sunk or damaged 18 U.S. ships, and destroyed or damaged more than 200 U.S. planes._^<g_See also: _^<a!T33462_United States, history of the_^>a_; _^<a!T35546_Yamamoto Isoroku_^>a_. _^<g_
Approximately 100,000 people were killed on Aug. 6, 1945, when a _^<a!T33459_United States_^>a_ warplane leveled the Japanese city of _^<a!T15842_Hiroshima_^>a_ with a single _^<a!T2143_atomic bomb_^>a_. On August 9, the U.S. dropped its second atomic bomb, killing 40,000 in the city of _^<a!T23031_Nagasaki_^>a_. _^<a!T17427_Japan_^>a_ surrendered on Aug. 10, 1945, thus ending _^<a!T35397_World War II_^>a_._^<g_See also: _^<a!T17428_Japan, history of_^>a_; _^<a!T23965_nuclear weapon_^>a_._^<g_
A _^<a!T33451_United Nations_^>a_ coalition led by the _^<a!T33459_United States_^>a_ battled North Korea to a stalemate in the _^<a!T18614_Korean War_^>a_ of 1950-53. _^<a!T29409_Seoul_^>a_ changed hands four times. The coalition was cobbled together in response to North Korea's invasion of the South. North Korea was allied with Communist China and was helped materially by the USSR. _^<g_See also: _^<a!T7568_cold war_^>a_; _^<a!T18610_Korea, history of_^>a_; _^<a!T20378_MacArthur, Douglas_^>a_._^<g_
Democrat John F. _^<a!T18212_Kennedy_^>a_ defeated Republican Richard M. _^<a!T23737_Nixon_^>a_ in the 1960 American presidential election and thus became the first Roman Catholic and the youngest person ever elected to the office. Kennedy's term occurred at the height of the _^<a!T7568_cold war_^>a_ with the Soviet Union. He was assassinated on Nov. 22, 1963, in Dallas, Texas._^<g_See also: _^<a!T8612_Cuban Missile Crisis_^>a_; _^<a!T33435_Union of Soviet Socialist Republics_^>a_; _^<a!T33462_United States, history of the_^>a_._^<g_
U.S. involvement in the _^<a!T34008_Vietnam War_^>a_ intensified in 1964 when President Lyndon B. _^<a!T17694_Johnson_^>a_ received Congressional authorization to conduct military operations. Previously, the U.S. had restricted its military role to advising South Vietnam against Communist insurgents from North Vietnam. The U.S. withdrew in 1973._^<g_See also: _^<a!T15884_Ho Chi Minh_^>a_; _^<a!T32701_Tonkin Gulf Resolution_^>a_; _^<a!T34003_Viet Cong_^>a_; _^<a!T34006_Vietnam_^>a_._^<g_
Richard M. _^<a!T23737_Nixon_^>a_, a Republican, became the 37th president of the _^<a!T33459_United States_^>a_ in 1969. Although widely praised for his foreign policy and his withdrawal of U.S. troops from _^<a!T34006_Vietnam_^>a_, Nixon's legacy rests on his role in the _^<a!T34561_Watergate_^>a_ scandal. In 1974, he became the first U.S. president to resign._^<g_See also: _^<a!T16753_impeachment_^>a_; _^<i__^<a!T33481_United States v. Richard M. Nixon_^>a__^>i_._^<g_
Named for the U.S. presidential retreat where negotiations occurred between the protagonists, the Camp David Accords (1979) made peace between _^<a!T10685_Egypt_^>a_ and _^<a!T17231_Israel_^>a_. Under this treaty, Israel returned the Sinai peninsula to Egypt. U.S. President Jimmy _^<a!T6024_Carter_^>a_ mediated the talks which led to the treaty._^<g_See also: _^<a!T1636_Arab-Israeli Wars_^>a_; _^<a!T3184_Begin, Menachem_^>a_; _^<a!T5585_Camp David_^>a_; _^<a!T21901_Middle East, history of the_^>a_; _^<a!T24816_Palestine_^>a_; _^<a!T28391_Sadat, Anwar al-_^>a_._^<g_
Rosa _^<a!T25021_Parks_^>a_ was a key figure in the movement for _^<a!T7205_civil rights_^>a_ for American blacks. In December 1955, Parks, a black American, was arrested for refusing to surrender her bus seat to a white man. The incident triggered the Montgomery bus boycott and galvanized civil rights activists in the South._^<g_See also: _^<a!T402_African Americans_^>a_; _^<a!T9767_discrimination_^>a_._^<g_
The Civil Rights Act of 1964 was the capstone of the American _^<a!T7205_civil rights_^>a_ movement begun in the early 1950s. Under this federal legislation, racial _^<a!T9767_discrimination_^>a_ in employment, accommodations, restaurants and theaters was prohibited. The act also created the Equal Employment Opportunity Commission._^<g_See also: _^<a!T7206_Civil Rights Acts_^>a_; _^<a!T7207_Civil Rights Cases_^>a_; _^<a!T11159_equal opportunity_^>a_; _^<a!T18389_King, Martin Luther, Jr._^>a_; _^<a!T25021_Parks, Rosa_^>a_; _^<a!T33462_United States, history of the_^>a_._^<g_
_^<a!T18389_Martin Luther King, Jr._^>a_, was the foremost figure in the American _^<a!T7205_civil rights_^>a_ movement in the 1950s and 1960s. In 1957, King, a member of the clergy in Montgomery, Ala., organized the nonviolent _^<a!T30509_Southern Christian Leadership Conference_^>a_ which would be the focal point of the movement. King won the Nobel Peace Prize in 1964. He was assassinated in Memphis, Tenn. in 1968._^<g_See also: _^<a!T402_African Americans_^>a_; _^<a!T23751_Nobel Prize_^>a_._^<g_
The left-wing Sandinista National Liberation Front overthrew the Nicaraguan dictator Anastasio Somoza Debayle in 1979 and held power until the democratic elections of 1990. The ruling junta, headed by Daniel Ortega Saavedra, battled U.S.-backed anti-Sandinista guerrillas for 10 years before the election._^<g_See also: _^<a!T24541_Ortega Saavedra, Daniel_^>a_; _^<a!T28724_Sandinistas_^>a_; _^<a!T30411_Somoza (family)_^>a_._^<g_
On Jan. 28, 1986, the American _^<a!T30546_Space Shuttle_^>a_ _^<i_Challenger_^>i_ exploded shortly after liftoff from the _^<a!T18218_Kennedy Space Center_^>a_, killing the crew of seven, among them civilian schoolteacher _^<a!T20386_Christa McAuliffe_^>a_. A commission later determined that a faulty seal triggered the chain of events which led to the explosion._^<g_See also: _^<a!T30545_space programs, national_^>a_._^<g_
Modern _^<a!T17231_Israel_^>a_ was established on May 14, 1948, twenty-six years after Great Britain, as part of a League of Nations mandate, pledged to establish a Jewish homeland in Palestine. The upheavals of World War II, including the decimation of European Jewry in the _^<a!T15992_Holocaust_^>a_, had accelerated the movement to establish a Jewish homeland._^<g_See also: _^<a!T1636_Arab-Israeli Wars_^>a_; _^<a!T3320_Ben-Gurion, David_^>a_; _^<a!T17572_Jews_^>a_; _^<a!T21901_Middle East, history of the_^>a_._^<g_
Total victory in the Six-Day War of 1967 gave _^<a!T17231_Israel_^>a_ the _^<a!T29964_Sinai_^>a_, _^<a!T13324_Gaza_^>a_, Arab _^<a!T17544_Jerusalem_^>a_, the _^<a!T34795_West Bank_^>a_, and the Golan Heights. This was one of the four major wars and many skirmishes which have marked the hostility between Israel and its Arab neighbors since the founding of the state of Israel in 1948. The first war occurred in 1947-49 and firmly established Israel as a state. Other wars were fought in 1956 and 1973._^<g_See also: _^<a!T1636_Arab-Israeli Wars_^>a_; _^<a!T13325_Gaza Strip_^>a_; _^<a!T17052_intifada_^>a_; _^<a!T21901_Middle East, history of the_^>a_._^<g_
The October 1973 Arab-Israeli War triggered an Arab oil embargo against the Western countries who supported Israel. The action amplified an existing, underlying trend of rising oil prices. Within a few months of the embargo, however, petroleum prices tripled, plunging oil-importing countries into economic crisis._^<g_See also: _^<a!T1636_Arab-Israeli Wars_^>a_; _^<a!T11024_energy sources_^>a_; _^<a!T24489_Organization of Petroleum Exporting Countries_^>a_._^<g_
The _^<a!T18313_Ayatollah Ruhollah Khomeini_^>a_ returned from exile in France in 1979 to lead _^<a!T17103_Iran_^>a_ following the overthrow of the shah. Khomeini sought to transform Iran from a secular state to one based on _^<a!T17192_Islam_^>a_, and he used anti-Western hostility and the Iran-Iraq War of 1980-88 to unite the country._^<g_See also: _^<a!T17106_Iranian hostage crisis_^>a_; _^<a!T22767_Muhammad Reza Shah Pahlavi_^>a_._^<g_
In 1993 and 1994, _^<a!T17231_Israel_^>a_ and its Arab neighbors accelerated the movement toward peace in the _^<a!T21900_Middle East_^>a_. In 1993, Israel and the _^<a!T24817_Palestine Liberation Organization_^>a_ reached agreement on a variety of issues as a first step toward ending long-standing antagonism between the two. In 1994, Israel and _^<a!T17788_Jordan_^>a_ formally ended their state of war and worked toward a comprehensive peace accord._^<g_See also: _^<a!T1636_Arab-Israeli Wars_^>a_; _^<a!T1651_Arafat, Yasir_^>a_; _^<a!T16473_Hussein I, King of Jordan_^>a_; _^<a!T21901_Middle East, history of the_^>a_._^<g_
Joseph _^<a!T30818_Stalin_^>a_ consolidated power as the preeminent Soviet leader from 1924 to 1929. From 1929 until his death in 1953, Stalin ruled the Soviet Union in one of the most ruthless regimes in history. His death touched off a power struggle, which ended when Nikita _^<a!T18321_Khrushchev_^>a_ emerged (1956) as the leader of the Soviet Union._^<g_See also: _^<a!T33435_Union of Soviet Socialist Republics_^>a_._^<g_
_^<i_Sputnik 1_^>i_ was the first artificial satellite. Launched by the USSR on Oct. 4, 1957, the 84-kg (184-lb) _^<i__^<a!T30766_Sputnik_^>a__^>i_ marked the opening of the space age. Its success ignited a _^<a!T7568_cold war_^>a_ race between the _^<a!T33459_United States_^>a_ and the Soviet Union to command the technological high ground of space for scientific and military purposes._^<g_See also: _^<a!T28865_satellite, artificial_^>a_; _^<a!T30545_space programs, national_^>a_. _^<g_
The October 1962 standoff between the Soviet Union and the United States over nuclear missiles on Cuba is known as the _^<a!T8612_Cuban Missile Crisis_^>a_. U.S. reconnaissance flights took pictures which showed the construction of missile-launching sites in Cuba; the U.S. blockaded Cuba in response. The crisis ended when the Soviets dismantled the sites._^<g_See also: _^<a!T7568_cold war_^>a_; _^<a!T18212_Kennedy, John F._^>a_; _^<a!T18321_Khrushchev, Nikita Sergeyevich_^>a_._^<g_
The post-World War II period of intense struggle for political and economic hegemony between the _^<a!T33459_United States_^>a_ and the _^<a!T33435_Union of Soviet Socialist Republics_^>a_ is known as the _^<a!T7568_cold war_^>a_. The war, which began in 1947 and was fought mainly by proxy armies in regional conflicts, ended when the USSR dissolved in 1991._^<g_See also: _^<a!T14035_Gorbachev, Mikhail_^>a_; _^<a!T33070_Truman, Harry S._^>a_; _^<a!T33462_United States, history of_^>a_._^<g_
Mikhail _^<a!T14035_Gorbachev_^>a_ was the last leader of the _^<a!T33435_Union of Soviet Socialist Republics_^>a_. As general secretary of the Communist party from 1985 to 1991, and as president from 1988 to 1991, Gorbachev steered the Soviet Union through a series of reforms designed to invigorate a decaying society. The reforms led to the disappearance of the USSR._^<g_See also: _^<a!T7745_communism_^>a_; _^<a!T13759_glasnost_^>a_._^<g_
Reforms unleashed in the 1980s by Soviet president Mikhail _^<a!T14035_Gorbachev_^>a_ spun out of his control by 1990 and led to the disintegration of the _^<a!T33435_Union of Soviet Socialist Republics_^>a_ late in 1991. The Soviet Communist party had lost its monopolistic grip on politics in 1990, and satellite states and republics declared their independence._^<g_See also: _^<a!T7745_communism_^>a_; _^<a!T25408_perestroika_^>a_._^<g_
U.S. Secretary of State George C. _^<a!T21128_Marshall_^>a_ framed a post-_^<a!T35397_World War II_^>a_ program of economic and technical assistance to 16 war-ravaged European countries. It became known as the _^<a!T21138_Marshall Plan_^>a_. The program, first proposed in 1947 and implemented from 1948 to 1952, helped to restore the economies of western Europe and triggered increases in world trade._^<g_See also: _^<a!T7568_cold war_^>a_; _^<a!T12438_foreign aid_^>a_._^<g_
The European Economic Community, now known as the _^<a!T11412_European Union_^>a_ (EU), can trace its roots to the 1952 founding of the European Coal and Steel Community. The EEC itself was formalized in 1958 and has since evolved to pan-European status with its own parliament and rules._^<g_See also: _^<a!T8729_customs union_^>a_; _^<a!T9339_Delors, Jacques_^>a_; _^<a!T11397_Europe, history of_^>a_._^<g_
British troops began to arrive in Northern Ireland in 1969 to maintain order after clashes between Catholic civil rights demonstrators and Protestants. Terrorist attacks by the _^<a!T17133_Irish Republican Army_^>a_ and its Protestant counterparts amplified the violence and increased the military presence._^<g_See also: _^<a!T14297_Great Britain, history of_^>a_; _^<a!T17111_Ireland, history of_^>a_._^<g_
Non-Communist governments began to replace the political regimes of Eastern Europe in 1989 as part of Mikhail Gorbachev's program to relax the Soviet Union's grip on its satellite regimes. The dissolution of the USSR itself in 1991 virtually eliminated Communism from the European political map._^<g_See also: _^<a!T7745_communism_^>a_; _^<a!T11397_Europe, history of_^>a_; _^<a!T33435_Union of Soviet Socialist Republics_^>a_._^<g_
Victory by South Africa's National Party in 1948 began the country's era of _^<a!T1543_apartheid_^>a_, a complex system of racial segregation developed to maintain white dominance. The system began to crumble in 1989 and ceased to exist in 1994 when nonracial elections led to the installation of Nelson _^<a!T20876_Mandela_^>a_ as prime minister._^<g_See also: _^<a!T412_African National Congress_^>a_; _^<a!T9145_de Klerk, F. W._^>a_._^<g_
African colonies divided by 19th-century European powers secured their independence, beginning in the early 1950s and continuing through the late-1970s. The _^<a!T31317_Sudan_^>a_ gained independence in 1956. By 1962, more than 24 colonies had become independent nation-states. In 1979, Southern Rhodesia became independent _^<a!T35855_Zimbabwe_^>a_._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T4784_British Empire_^>a_; _^<a!T7636_colonialism_^>a_; _^<a!T12792_French colonial empire_^>a_._^<g_
Roughly 2 million people died in famines that rolled for two decades throughout _^<a!T11325_Ethiopia_^>a_. Famine struck in 1972-74, 1984-85, 1987, and 1989-90. International donors rallied global support to alleviate the suffering. The many causes of famine included drought and failed food-production programs._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T11675_famine_^>a_; _^<a!T30881_starvation_^>a_._^<g_
Nelson _^<a!T20876_Mandela_^>a_ became (1994) South Africa's first prime minister under its new nonracial constitution and elections. Mandela, a black political activist and lawyer, had been jailed in 1964 for conspiring to overthrow the white government and spent 26 years in prison before he was released._^<g_See also: _^<a!T412_African National Congress_^>a_; _^<a!T30480_South Africa_^>a_._^<g_
_^<a!T20966_Mao Zedong_^>a_ (Mao Tse-tung) proclaimed the People's Republic of _^<a!T6872_China_^>a_ in 1949 after defeating Chinese nationalists. The communist assumption of power in China led to land reform measures, equal rights for women, improved sanitation, and attempts to achieve universal literacy. The losing nationalists fled to Taiwan._^<g_See also: _^<a!T6795_Chiang Kai-shek_^>a_; _^<a!T7745_communism_^>a_; _^<a!T18614_Korean War_^>a_._^<g_
A vast effort by _^<a!T6872_China_^>a_ to drive its economy toward western levels began in 1958 under the direction of _^<a!T20966_Mao Zedong_^>a_ (Mao Tse-tung), who called it the _^<a!T14308_Great Leap Forward_^>a_. The effort failed, however, and millions died of starvation. The disaster cost Mao his position as head of state, but he remained as chief of the Communist party._^<g_See also: _^<a!T7745_communism_^>a_; _^<a!T19857_Liu Shaoqi (Liu Shao-ch'i)_^>a_._^<g_
In 1949, _^<a!T20966_Mao Zedong_^>a_ founded the People's Republic of _^<a!T6872_China_^>a_. He led the country for most of the next twenty-seven years. Throughout, Mao followed Marxist philosophy. However, plans for economic development, including the _^<a!T14308_Great Leap Forward_^>a_, failed, and Mao briefly lost influence in the 1950s. He reasserted political control over China in the 1960s and held power until his death in 1976._^<g_See also: _^<a!T6873_China, history of_^>a_; _^<a!T8637_Cultural Revolution_^>a_._^<g_
The state-planned Chinese economy was liberalized in the mid-1980s under the influence of _^<a!T9388_Deng Xiaoping (Teng Hsiao-p'ing)_^>a_. Private-market reforms were initiated to promote internal growth and trade with non-Communist nations. By the mid-1990s, China had one of the fastest-growing economies in the world._^<g_See also: _^<a!T5785_capitalism_^>a_; _^<a!T6873_China, history of_^>a_._^<g_
The victorious World War II allies led by the United States and U.S. Gen. Douglas _^<a!T20378_MacArthur_^>a_ occupied _^<a!T17427_Japan_^>a_ from 1945 to 1952. The occupation generated political, social, and economic reforms, and Japan was required under its new constitution to renounce its right to use force._^<g_See also: _^<a!T15839_Hirohito, Emperor of Japan_^>a_; _^<a!T17428_Japan, history of_^>a_; _^<a!T24235_Okinawa_^>a_._^<g_
Between 1954 and 1972, the Japanese economy rebounded from the disaster of World War II by averaging 10 percent annual growth. The government steered private investment to growth areas, such as electronics. By the mid-1970s, Japan led the world in _^<a!T29723_shipbuilding_^>a_ and was among the top in manufacturing._^<g_See also: _^<a!T10587_economic planning_^>a_; _^<a!T10826_electronics_^>a_; _^<a!T17428_Japan, history of_^>a_; _^<a!T20956_manufacturing, history of_^>a_._^<g_
A symbol of 20th-century _^<a!T17427_Japan_^>a_ in both war and peace, Emperor _^<a!T15839_Hirohito_^>a_ reigned over the country for 62 years until his death in 1989. His reputation was tarnished by Japan's militaristic political governments in the 1930s and 1940s, but his influence was credited with bringing _^<a!T35397_World War II_^>a_ to a close in 1945._^<g_See also: _^<a!T17428_Japan, history of_^>a_._^<g_
_^<a!T35397_World War II_^>a_ began in eastern Europe in 1939, when Germany attacked Poland, but within two years the conflict had engulfed the globe. Roughly 45 million people, civilians and combatants, had been killed by the time hostilities ceased in 1945, the price the U.S. and its allies paid for halting German and Japanese aggression._^<g_See also: _^<a!T15873_Hitler, Adolf_^>a_; _^<a!T15992_Holocaust_^>a_; _^<a!T31175_strategy and tactics, military_^>a_._^<g_
Idi Amin seized dictatorial control of _^<a!T33345_Uganda_^>a_ in 1971. Under his rule, about 300,000 Ugandans died in various purges, and the country fell into economic disarray. Amin gained power by toppling Prime Minister Milton Obote. In 1979, Tanzanian troops invaded Uganda and sent Amin into exile._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T1140_Amin Dada, Idi_^>a_; _^<a!T24071_Obote, Milton_^>a_._^<g_
A series of military losses and damaging concessions to foreign empires triggered a movement between June and September 1898 to form a Chinese constitutional monarchy in the name of Confucius. The movement failed when Empress Cixi imprisoned the emperor and withdrew his reform edicts to protect Qing dynastic interests._^<g_See also: _^<a!T6873_China, history of_^>a_; _^<a!T7218_Cixi, Dowager Empress of China (Tz'u-hsi)_^>a_._^<g_
Approximately 6 million Africans lost their freedom in the 18th century at the height of the African slave trade. English ships cruised the west coast of _^<a!T396_Africa_^>a_. Captains traded merchandise for black Africans, who, in turn, were exchanged for agricultural products of North America. The trade in human flesh became so lucrative that a sliver of west African coastline near the Senegal River and north of the Niger River Delta became known as the "Slave Coast."_^<g_The slave trade gathered steam and began to reach its peak in 1720. More than 2,000 ships sailing from Liverpool, England, to West Africa in the 18th century were involved in the slave trade. Tens of thousands of Africans perished, particularly during the "Middle Passage" from Africa to the West Indies. Ship owners herded as many people as possible into the airless, disease-ridden holds of their vessels. Once ashore, slaves were often branded, or maimed, to prevent escape. Many were hanged for rebelling._^<g_Opposition to _^<a!T30103_slavery_^>a_ slowly surfaced in the 18th century when French Enlightenment intellectuals _^<a!T22439_Montesquieu_^>a_ and Jean Jacques _^<a!T28146_Rousseau_^>a_ attacked slavery as part of their broader assault on social and political injustice. With moral force behind them and unceasing energy, _^<a!T81_abolitionists_^>a_ emerged in England and the United States to launch a widespread attack against slavery. It worked. The northern states of the U.S. had banned slavery by the early 19th century. England ended its participation in the African slave trade in 1807 and outlawed it in 1833._^<g_The U.S. banned the slave trade in 1808, but slavery persisted there until the North defeated the South in a bloody _^<a!T7213_Civil War_^>a_ (1861-65). South American countries outlawed slavery when they won independence from European colonial empires during the 19th century. The list of abolitionists who worked tirelessly to end slavery in the U.S. included William Lloyd _^<a!T13246_Garrison_^>a_, Frederick _^<a!T10056_Douglass_^>a_, Angelina Grimke, Wendell _^<a!T25673_Phillips_^>a_, and Theodore _^<a!T34717_Weld_^>a_._^<g_See also: _^<a!T14482_Grimke, Sarah Moore and Angelina Emily_^>a_._^<g_
Under the Manchu dynasty, _^<a!T6872_China_^>a_ asserted its military and political influence over _^<a!T1993_Asia_^>a_ to an extent not seen since the 9th century. In 1720, _^<a!T32459_Tibet_^>a_ became a tributary, to be followed by Burma and then _^<a!T23377_Nepal_^>a_, in 1792. The Manchus also compelled _^<a!T1396_Annam_^>a_ (_^<a!T34006_Vietnam_^>a_) to yield to Chinese hegemony, bringing Southeast Asia under their sway._^<g_See also: _^<a!T1995_Asia, history of_^>a_; _^<a!T6873_China, history of_^>a_; _^<a!T22970_Myanmar_^>a_; _^<a!T26941_Qianlong (Ch'ien-lung)_^>a_._^<g_
At the turn of the 20th century, the United States remained divided despite the ebbing of the bitterness brought on by the U.S. Civil War. In the South, _^<a!T17586_Jim Crow laws_^>a_ supported by the Supreme Court had legalized segregation. In the North, a violent backlash against immigrants persisted. Moreover, the settling of the _^<a!T12891_frontier_^>a_ closed what had been a convenient outlet for the country's seemingly inherent wanderlust. Between 1900 and 1994, the United States evolved into a global superpower, one capable of enduring a century-long train of events that consistently threatened its existence as a capitalist democracy._^<g_In both 1917-1918 and 1941-45, the United States emerged victorious in two global wars. After _^<a!T35394_World War I_^>a_, the victorious Americans retreated into their traditional position of isolationism and enjoyed an economic boom that lasted for nearly 10 years. After _^<a!T35397_World War II_^>a_, the U.S. constructed global economic and political dominance over the West. In the years between the wars, however, the U.S. endured the deepest economic dislocation in its history, the Great Depression. At the Depression's peak in 1933, unemployment hit 25 percent and national income had been cut by half. President Franklin D. _^<a!T28032_Roosevelt_^>a_ pushed several measures through Congress, but high unemployment and misery persisted until the U.S. entered (1941) World War II. Massive spending to meet the war emergency ended the Depression._^<g_Ideological conflicts with the Soviet Union erupted in 1947, and were held in check only by the armed truce that lasted from 1947 to 1991. During that time, the U.S. and the Soviets engaged in a series of proxy wars from Central America and Central Asia to Africa. The U.S. sent troops to _^<a!T23854_North Korea_^>a_ (1950-53) and _^<a!T34006_Vietnam_^>a_ (1964-73) to support its doctrine. The _^<a!T18614_Korean War_^>a_ ended in stalemate; the _^<a!T34008_Vietnam War_^>a_ in failure._^<g_A series of social revolutions in the 1950s and 1960s rocked the U.S. Beginning with the 1954 Supreme Court decision that struck down the "separate but equal" doctrine, the movement for _^<a!T7205_civil rights_^>a_ for American blacks gained momentum under the leadership of Dr. Martin Luther _^<a!T18389_King_^>a_, Jr. Women's rights movements emerged in the 1960s. Street protests over U.S. involvement in Vietnam and urban riots dominated the U.S. in the late 1960s, despite the technological achievement of landing two astronauts on the moon (1969). By 1974, the U.S. seemed exhausted and adrift, and the resignation of President Richard _^<a!T23737_Nixon_^>a_ under the threat of impeachment seemed to amplify the malaise._^<g_In 1981-82, the worst economic crisis since the Great Depression rolled through the U.S., but an enormous military buildup under President Ronald _^<a!T27317_Reagan_^>a_ triggered a seven-year economic expansion that restored American military and economic power. In 1989, the Soviet Union jettisoned its grip on Eastern Europe, signaling the end of the _^<a!T7568_cold war_^>a_ two years later when the Soviet Union collapsed. In 1991, the U.S. headed a global coalition that ousted _^<a!T17107_Iraq_^>a_ from _^<a!T18771_Kuwait_^>a_, but economic slowdown dampened the celebrations. In 1992 George _^<a!T5260_Bush_^>a_ lost the presidency to Bill _^<a!T7366_Clinton_^>a_, ending the Republicans' 12-year hold on the White House._^<g_See also: _^<i__^<a!T4940_Brown v. Board of Education of Topeka, Kansas_^>a__^>i_; _^<a!T23467_New Deal_^>a_; _^<a!T30541_space exploration_^>a_._^<g_
The _^<a!T33435_Union of Soviet Socialist Republics_^>a_ grew out of the turbulence of Russia's revolutions and civil war between 1917 and 1921. For most of the 20th century, the USSR was the world's largest country, covering 11 time zones and more than 100 nationalities. In 1991, however, the Soviet Union disintegrated under the weight of economic decay and a political renaissance triggered by Mikhail _^<a!T14035_Gorbachev_^>a_. By 1994, _^<a!T28284_Russia_^>a_ had withdrawn into its traditional boundaries within a welter of newly independent nations._^<g_The establishment of the Union of Soviet Socialist Republics (1922) occurred after almost a decade of chaos and upheaval in Russia. The Bolsheviks, headed by V.I. Lenin, launched a successful coup in November 1917 against a weak provisional government and then survived a three-year civil war. Followers of Marxism, the Bolsheviks sought to build a strong central government and eliminate private ownership of land and economic assets. In 1922, Lenin designed a federal constitution, incorporating the Russian Republic, Belorussia, and the Transcaucasian republic into a new entity, the Union of Soviet Socialist Republics. The Soviets would later absorb the Baltic states of _^<a!T11302_Estonia_^>a_, _^<a!T19830_Lithuania_^>a_ and _^<a!T19166_Latvia_^>a_, and they would eventually extend hegemony over Eastern Europe._^<g_In 1924, Lenin died. Over the next four years, Joseph _^<a!T30818_Stalin_^>a_ accumulated power from his base as general secretary of the Communist party and by 1929 had emerged as the undisputed ruler of the country. He centralized industrial planning and collectivized agricultural production. Political opponents were either killed or exiled through systematic purges. He forced millions of peasants off the land. Famines leading to deaths of millions occurred in the 1930s. Yet Stalin faced few threats to his dictatorial rule. After _^<a!T35397_World War II_^>a_, the Soviet Union installed Communist regimes throughout Eastern Europe, creating a system of nominally independent satellite states that became puppets of the regime in Moscow. The Soviet Union built a vast nuclear arsenal and consistently challenged the alliance of western democracies headed by the United States by supporting Marxist regimes around the world. When Stalin died (1953), the Soviet Union was a superpower. The _^<a!T7568_cold war_^>a_ with the United States was underway._^<g_After Stalin's death, Nikita _^<a!T18321_Khrushchev_^>a_ slowly gained control of the political apparatus. Although he repudiated Stalinism and relaxed domestic life by allowing dissent, he continued to follow some Stalinist policies. Khrushchev sent Soviet troops to crush a revolt against the communist regime in _^<a!T16414_Hungary_^>a_ in 1956. He attempted to install nuclear missiles in _^<a!T8611_Cuba_^>a_, prompting the _^<a!T8612_Cuban Missile Crisis_^>a_ of October 1962. By 1964, Khrushchev had fallen from the party leadership. Under the next undisputed leader, Leonid I. _^<a!T4715_Brezhnev_^>a_, the Soviet economy stagnated. When Brezhnev died in 1982, the Soviet Union was close to economic collapse. In 1985, Mikhail Gorbachev became the party leader, and instituted a series of reforms called _^<a!T13759_glasnost_^>a_ and _^<a!T25408_perestroika_^>a_ to reverse the country's economic decline. He called for an end to state economic planning and allowed Eastern Europe to break free of Soviet control. The political momentum he had ignited led to the disintegration of the Soviet Union in December 1991, as a series of republics declared their independence and formed governments, many fashioned on the democratic model._^<g_See also: _^<a!T3222_Belarus_^>a_; _^<a!T4172_Bolsheviks and Mensheviks_^>a_; _^<a!T11675_famine_^>a_._^<g_
The 18th century marked the second wave of world exploration by European mariners. The first, which covered the 15th, 16th, and, to a lesser extent, the 17th century, enriched European treasuries and stomachs. For example, _^<a!T8156_corn_^>a_, unknown outside the New World before Columbus, was soon cultivated throughout Europe. The _^<a!T26373_potato_^>a_ plant, taken from the Peruvian Andes by Spanish explorers, was soon grown in Spain, Switzerland and Ireland. In addition, the mariners triggered a long and sometimes bloody process of colonial expansion, pitting European power against European power over territories in the western hemisphere. Native people such as the North American Indians were either wiped out, forced to move away from land near white settlements or assimiliated into western culture throughout the period. _^<g_The 18th-century wave of _^<a!T11533_exploration_^>a_ would bring more excitement and goods to Europe, principally from the islands of the _^<a!T24732_Pacific Ocean_^>a_. Although the Pacific Ocean had been explored and many islands and continents had been discovered, the region's vastness insured that there would be new areas ripe for discovery. The pattern of conquest and displacement of indigenous people as established in North America continued in the Pacific. Capt. James _^<a!T8040_Cook_^>a_ emerged as the notable mariner of the period. Cook, an English common sailor who became more famous than well-born admirals of his day, made three voyages to the Pacific. In 1768-71, Cook went to _^<a!T31697_Tahiti_^>a_, _^<a!T23530_New Zealand_^>a_ and _^<a!T2259_Australia_^>a_, which had previously been discovered. From 1772 to 1775, Cook crossed and recrossed the Pacific Ocean, but made no significant discoveries. Cook's greatest voyage began in 1776. He discovered the Hawaiian Islands, moved to the western coast of America and sought a Pacific outlet to the _^<a!T23887_Northwest Passage_^>a_. He was killed in 1799 in a scuffle with Hawaiian islanders._^<g_Cook's voyages spawned a scramble to develop settlements in the southwest Pacific and in the American northwest. Australia (the dumping ground for English criminals) and New Zealand became key British colonies. Britain, _^<a!T30557_Spain_^>a_, the newly independent _^<a!T33459_United States_^>a_, _^<a!T12624_France_^>a_, and _^<a!T28284_Russia_^>a_ all competed to secure settlements and natural resources in the American northwest within 25 years of Cook's last voyage._^<g_Settlers of many nationalities continued their long march across the North American continent. Building communities first on the eastern seaboard, successive generations and immigrants moved inexorably west, across the _^<a!T1587_Appalachian Mountains_^>a_ and the Piedmont to the _^<a!T22150_Mississippi River_^>a_. The United States, which secured its independence from Britain in 1783, stretched from the Atlantic to the western side of the Mississippi River by the early 19th century. Each extension of the _^<a!T12891_frontier_^>a_ was accompanied by waves of people seeking a new life. _^<g_See also: _^<a!T15259_Hawaii (state)_^>a_._^<g_
Science had little impact on most Westerners until the 18th century, when the rapid accumulation of knowledge suddenly changed the way people lived and worked._^<g_The wide dissemination of knowledge, spurred by the _^<a!T26581_printing_^>a_ press and growing literacy rates in Europe, helped fuel the impact of science. Western society moved from the farm to the city, and new forms of _^<a!T7742_communication_^>a_ and _^<a!T32878_transportation_^>a_ accelerated the pace of everyday life. The universe of the late-19th century would be unrecognizable to someone who lived just a few generations earlier. In short, the modern, secular, industrialized world took shape between 1700 and 1900._^<g_Prior to the 18th century, science took form by modeling the universe on abstract mathematical principles. In less than 100 years, however, the idea of the universe as a machine seeped into Europe's collective consciousness and triggered an enormous upheaval based on economic necessity. With trees--the source of the charcoal needed to smelt iron--disappearing rapidly from England, Abraham Darby I developed (1709) _^<a!T7551_coke_^>a_, a byproduct of _^<a!T7432_coal_^>a_. The _^<a!T16861_Industrial Revolution_^>a_ was underway, but coal mines--opening en masse to fuel the new coke-based iron smelters--would often close because their shafts were filled with water. Thomas _^<a!T23545_Newcomen_^>a_ solved that problem by designing a steam-powered engine to pump water. In 1763, James _^<a!T34586_Watt_^>a_, who made mathematical instruments, added to Newcomen's basic design and developed steam engines for a variety of uses, including transportation. Steam transportation, by boat and by a new marvel, the railway, linked countries from north to south, east to west. By 1867 the vast expanses of the United States were unified. Travel times were cut enormously, further squeezing time and space._^<g_ The rapid pace of innovation and _^<a!T17063_invention_^>a_ continued through the late-18th and 19th centuries. The cotton _^<a!T32186_textile industry_^>a_ was fully mechanized in Britain and the United States. Inventions such as John _^<a!T18127_Kay_^>a_'s flying shuttle, James _^<a!T15078_Hargreaves_^>a_' spinning jenny, and Edmund _^<a!T6047_Cartwright_^>a_'s machine loom were critical to the development of the early textile manufacturing system. In 1793, Eli _^<a!T34943_Whitney_^>a_ invented the _^<a!T8277_cotton gin_^>a_; he would later adopt the European process of interchangeable parts to produce exact copies of guns in large quantities. Thomas Alva _^<a!T10627_Edison_^>a_ produced the first practical _^<a!T16774_incandescent lamp_^>a_ (1879) and developed the world's first central electric light-power station (1882). Samuel _^<a!T22611_Morse_^>a_'s electric _^<a!T32012_telegraph_^>a_ (1837) and Alexander Graham Bell's _^<a!T32020_telephone_^>a_ (1876) revolutionized communications. Michael _^<a!T11698_Faraday_^>a_ demonstrated the principle of induction in 1831; this made possible a mechanical _^<a!T13391_generator_^>a_ to produce electricity. In 1859, the first oil well was drilled, in Titusville, Penn., thus heralding the age of _^<a!T16524_hydrocarbons_^>a_, which would dominate the 20th century._^<g_Outside of applied science, pure research continued to reconfigure the world view. In 1859, Charles _^<a!T8997_Darwin_^>a_ published _^<i_On the Origin of Species,_^>i_ which formulated the theory of biological _^<a!T11480_evolution_^>a_ by _^<a!T23253_natural selection_^>a_ and revolutionized the study of _^<a!T3711_biology_^>a_._^<g_See also: _^<a!T3245_Bell, Alexander Graham_^>a_; _^<a!T8274_cotton_^>a_; _^<a!T8964_Darby (family)_^>a_; _^<a!T19816_literacy and illiteracy_^>a_; _^<a!T20956_manufacturing, history of_^>a_; _^<a!T27149_railroad_^>a_; _^<a!T29134_science, history of_^>a_; _^<a!T30923_steam engine_^>a_._^<g_
The concept of _^<a!T16376_human rights_^>a_ had been part of Western philosophical traditions of _^<a!T23250_natural law_^>a_, natural rights and liberal individualism since the _^<a!T11063_Enlightenment_^>a_ of the 18th century. Not until the 20th century, however, did human rights and international humanitarianism capture the moral high ground of political practice, even in the West._^<g_The movement toward codification of human rights gathered momentum in the 19th century, when Britain and the _^<a!T33459_United States_^>a_ outlawed _^<a!T30103_slavery_^>a_. In 1864, the Geneva Convention promulgated rules governing the treatment of wounded soldiers and prisoners of war. After _^<a!T35394_World War I_^>a_, the _^<a!T19278_League of Nations_^>a_ constructed international mechanisms to extend the ban throughout the world. In the first two decades of the 20th century, women's-suffrage supporters secured the right to vote for women in Britain and the United States._^<g_The horror of _^<a!T35397_World War II_^>a_ and the attempted extermination of European Jewry by Nazi _^<a!T13521_Germany_^>a_ accelerated the movement for human rights on a global scale. In 1945, the _^<a!T33451_United Nations_^>a_ framed its Declaration of Human Rights, which outlawed slavery and the slave trade. Three years later, the UN approved the Universal Declaration of Human Rights, which stated that the rights and freedoms enumerated in the declaration were to be enjoyed "without distinction of any kind, such as race, color, sex, language, religion, political or other opinion, national or social origin, property, birth, or other status."_^<g_Despite the UN's Universal Declaration of Human Rights, totalitarian regimes and some democracies continued to violate the letter and spirit of the document. It took a well-organized _^<a!T7205_civil rights_^>a_ movement in the United States and the establishment of anti-discrimination laws to end segregation practices against American blacks. Women continued to press unsuccessfully for an _^<a!T11161_Equal Rights Amendment_^>a_ to the Constitution. In the Soviet Union, thousands of political dissidents were imprisoned for decades or exiled for opposing the Communist regime._^<g_Minority and ethnic groups began to seek rights equal to majority populations in the 1960s. In the United States, movements arose to successfully press for laws to protect the rights of homosexuals and the disabled, particularly the right not to be discriminated against. Private groups such as _^<a!T1159_Amnesty International_^>a_ fought vigorously to free political prisoners in countries around the world, using publicity as a powerful weapon. The United States sought to use its economic leverage to compel _^<a!T6872_China_^>a_ to free political prisoners in the 1990s. South African blacks secured a pivotal victory for human rights when the white-minority government dismantled _^<a!T1543_apartheid_^>a_ laws and held free elections in 1994. Nelson _^<a!T20876_Mandela_^>a_, a black South African who had been held prisoner by the white government for decades, was elected prime minister of the country._^<g_See also: _^<a!T7745_communism_^>a_; _^<a!T9767_discrimination_^>a_; _^<a!T13407_Geneva conventions_^>a_; _^<a!T14296_Great Britain_^>a_; _^<a!T16969_integration, racial_^>a_; _^<a!T23290_Nazism_^>a_; _^<a!T30480_South Africa_^>a_; _^<a!T35298_women's rights movements_^>a_._^<g_
Science and _^<a!T31981_technology_^>a_ had been harnessed to the _^<a!T16861_Industrial Revolution_^>a_ by the opening of the 20th century. Major corporations in the U.S., Europe and Japan opened large research and development laboratories to link discovery with products and processes. Science and technology played critical roles in finding and exploiting the hidden potential of hydrocarbons (for _^<a!T25570_petroleum_^>a_) and _^<a!T33535_uranium_^>a_ (for nuclear energy)._^<g_Initially used as an illuminant in a distilled form, petroleum crept into the Industrial Revolution without much impact until the internal combustion engine was developed, in the late-19th century. When the _^<a!T2301_automobile_^>a_, with its gasoline-powered internal combustion engine, became a critical component of modern life early in the 20th century, petroleum became the second-most important commodity, after food. Gasoline-powered vehicles changed the nature of war, as highly mechanized and mobile units began to seize the day on the battlefield in _^<a!T35394_World War I_^>a_ and _^<a!T35397_World War II_^>a_. Gasoline engines spurred the development of _^<a!T2331_aviation_^>a_, too, beginning with the Wright brothers' 1903 invention of the airplane. New forms of warfare developed and travel time was shortened considerably. Agriculture became mechanized, increasing food production many times over to feed a growing global population._^<g_Science unlocked the power of the _^<a!T2142_atom_^>a_ in 1940, when research revealed that it would be possible to build a bomb using nuclear fission. Five years later, such a device was tested in a U.S. desert. In August 1945, U.S. warplanes dropped two atomic bombs on Hiroshima and Nagasaki in _^<a!T17427_Japan_^>a_, hastening the end of the war. The race among nations to build nuclear arsenals would come in the immediate aftermath of World War II and persist for decades._^<g_The marriage of science and technology provided a constant flow of new products that revolutionized a host of industries. The invention of the _^<a!T27101_radio_^>a_ (1896) by Guglielmo _^<a!T21011_Marconi_^>a_ led to a new, powerful and cheap communications medium for a range of uses, including maritime and military communication, entertainment and politics. Motion pictures became the leading source of public entertainment in this period, and early experiments with _^<a!T32025_television_^>a_ demonstrated its potential as yet another communications device that would have widespread impact on civilization._^<g_Pure science continued to be practiced with vigor. In 1900, Max _^<a!T25956_Planck_^>a_ formulated his idea that energy is emitted in packets, or in discrete quanta, instead of continuously. In 1905, Albert _^<a!T10718_Einstein_^>a_ put forth his special theory of _^<a!T27474_relativity_^>a_, which contradicted Sir Isaac Newton's notion of absolute motion in the universe. Einstein conceived of motion as relative to an observer. Einstein's universe of time and space was curved, not flat as scientists of earlier generations had speculated. Also in 1905, Einstein theorized that the mass of a body depended on its velocity and that greater velocity meant greater mass. That led him to conclude that mass and energy are linked in that energy depends on the size of the mass, and mass depends on velocity. Einstein expressed that concept in the famous equation E=mc_^<o!E301_. During the 1910s, Alfred Lothar _^<a!T34677_Wegener_^>a_ developed the theory of _^<a!T8007_continental drift_^>a_. In the 1920s, astronomer Edwin Powell _^<a!T16310_Hubble_^>a_ shifted concepts of the _^<a!T33494_universe_^>a_ by demonstrating that it was expanding. This led to the development of theories on the start of the universe._^<g_See also: _^<a!T549_aircraft_^>a_; _^<a!T2143_atomic bomb_^>a_; _^<a!T7742_communication_^>a_; _^<a!T12011_film, history of_^>a_; _^<a!T12125_fission, nuclear_^>a_; _^<a!T15842_Hiroshima (city)_^>a_; _^<a!T16524_hydrocarbon_^>a_; _^<a!T23031_Nagasaki_^>a_; _^<a!T23953_nuclear energy_^>a_; _^<a!T29134_science, history of_^>a_; _^<a!T35439_Wright, Orville and Wilbur_^>a_._^<g_
The formation of _^<a!T17231_Israel_^>a_ in 1948 tossed the Middle East into a bitter cycle of war and violence amplified by Arab nationalism and the West's dependence on the region's oil to fuel its industrial economies. In 1947, Britain, exhausted by the expense of World War II, decided to shed its League of Nations mandate over _^<a!T24816_Palestine_^>a_ and place the area's future into the newly formed _^<a!T33451_United Nations_^>a_. The UN voted to partition Palestine into two states, one Jewish and one Arab, with international status for the city of _^<a!T17544_Jerusalem_^>a_._^<g_Israel accepted in 1948, but Arab states rejected the plan and invaded Palestine hours after Israel declared itself to be a state. It would be the first of five _^<a!T1636_Arab-Israeli Wars_^>a_ between 1948 and 1982. The six-day conflict in 1967 greatly enlarged Israel, as its army captured the Golan Heights from _^<a!T31631_Syria_^>a_ and the _^<a!T29964_Sinai_^>a_ Peninsula from _^<a!T10685_Egypt_^>a_._^<g_Arab nationalism flowered in the 1950s under the charismatic leadership of Egyptian president Gamal Abdel _^<a!T23131_Nasser_^>a_, a military officer who seized power in 1954 after a coup sent King _^<a!T11726_Farouk_^>a_ into exile two years earlier. Nasser nationalized the Anglo-French _^<a!T31329_Suez Canal_^>a_ in 1956, prompting an Anglo-French-Israeli military reaction that failed and enhanced Nasser's reputation in the region. Nasser, however, never achieved his ultimate goal of a united Arab entity._^<g_In 1964, Arab nationalism underscored the formation of the _^<a!T24817_Palestine Liberation Organization_^>a_, which organized terrorist operations against Israel and formed a political regime in exile. The PLO became the de facto political and military organization for the Palestinian movement despite its difficulty in establishing a definitive presence in the region._^<g_Any chance of a united Arab entity collapsed in 1990 when _^<a!T17107_Iraq_^>a_ invaded _^<a!T18771_Kuwait_^>a_, touching off the _^<a!T25491_Persian Gulf War_^>a_ of 1991. A coalition of Arab and Western forces led by the United States soundly defeated Iraq and sought to isolate the Iraqi regime of Saddam _^<a!T16472_Hussein_^>a_ by maintaining military forces in the area to police an economic embargo and pressure the regime._^<g_Peace with Israel also chipped away at Arab unity, beginning in 1979 when Egyptian president Anwar al-_^<a!T28391_Sadat_^>a_ signed the _^<a!T5585_Camp David_^>a_ accords to end hostilities. In 1993, the PLO and Israel signed a peace accord, and in 1994, _^<a!T17788_Jordan_^>a_ and Israel agreed to end the state of war that existed between the two nations since 1948._^<g_Throughout the post-World War II period, the region's enormous oil reserves consistently added another layer of complexity to the region and kept the world's industrialized nations involved. The Arab-dominated _^<a!T24489_Organization of Petroleum Exporting Countries_^>a_ (OPEC) wielded its oil weapon against the West in the 1973 Arab-Israeli War by cutting off supplies and plunging the industrialized countries into a sharp cycle of recession and inflation._^<g_See also: _^<a!T14296_Great Britain_^>a_; _^<a!T21901_Middle East, history of_^>a_; _^<a!T25570_petroleum_^>a_._^<g_
European nations expanded their empires in _^<a!T1993_Asia_^>a_ and _^<a!T396_Africa_^>a_ in the 19th century while recovering from the loss of their North American colonies. Britain had lost most of its North American colonies to independence or self-governance by 1867. _^<a!T30557_Spain_^>a_'s colonial empire in the Americas had vanished by 1824, and _^<a!T26336_Portugal_^>a_ severed colonial ties with _^<a!T4635_Brazil_^>a_ a year later._^<g_The expansionist impulse persisted, fueled by nationalistic pride, the need for raw materials to facilitate the _^<a!T16861_Industrial Revolution_^>a_, and competition among nations. In North America, meanwhile, the _^<a!T12891_frontier_^>a_ of the _^<a!T33459_United States_^>a_ stretched ever westward, as swarms of immigrants and former colonists continued the inexorable movement away from the eastern seaboard, over the _^<a!T25787_Piedmont Plateau_^>a_ and the Appalachians, across the _^<a!T22150_Mississippi River_^>a_ toward the _^<a!T27921_Rocky Mountains_^>a_. By the end of the 19th century, the frontier had disappeared._^<g_For European nations, a new _^<a!T16757_imperialism_^>a_ emerged, with Asia and Africa serving as fodder for expansionist impulses. Although European nations had long-standing interests with Africa based on the slave trade, their conquest of the continent did not begin until the 19th century. Explorers such as Mungo _^<a!T24997_Park_^>a_, David _^<a!T19869_Livingstone_^>a_ and Sir Richard _^<a!T5252_Burton_^>a_ combined with Christian missionaries to map and inadvertently prepare the continent for European conquest. In 1830, _^<a!T12624_France_^>a_ claimed _^<a!T806_Algeria_^>a_, setting off a cascade of conquests that covered much of West Africa under the tricolor of France by the end of the 19th century. Britain, meanwhile, took _^<a!T10685_Egypt_^>a_, the _^<a!T31317_Sudan_^>a_ and _^<a!T33163_Tunisia_^>a_. _^<a!T26336_Portugal_^>a_, _^<a!T3235_Belgium_^>a_ and _^<a!T13521_Germany_^>a_ took what remained, completing the European partition of Africa._^<g_In Asia, France aggressively pursued a colonial empire. From the 1850s to 1893, France built an empire in Southeast Asia, combining what is now _^<a!T19074_Laos_^>a_, _^<a!T5545_Cambodia_^>a_, and _^<a!T34006_Vietnam_^>a_ into _^<a!T16837_Indochina_^>a_. Britain, too, busily collected colonies in 19th-century Asia, taking _^<a!T16799_India_^>a_ and Ceylon (now _^<a!T30785_Sri Lanka_^>a_), in addition to founding _^<a!T29973_Singapore_^>a_ as a colonial city-state._^<g_Unlike previous spasms of expansion, however, the 19th century's did not involve wholesale migration from the continent to the new colonies. Instead, European nations built commercial outposts to exploit natural resources and military bases to protect their lands and mercantile interests._^<g_The United States, too, shouldered its way into the empire-building club. A brief and victorious war with Spain in 1898 gave the U.S. significant stakes in the Pacific (_^<a!T25666_Philippines_^>a_) and the Caribbean (_^<a!T26810_Puerto Rico_^>a_). Within the country, meanwhile, major federal government land programs in the 19th century had opened the frontier to homesteaders, who quickly took land and built farms, communities and towns. The native population was systematically removed from vast areas of the west and placed on reservations controlled by the military. By 1890, the frontier had been settled. The era of westward expansion in the U.S. was over._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T1995_Asia, history of_^>a_; _^<a!T11397_Europe, history of_^>a_; _^<a!T11533_exploration_^>a_; _^<a!T14296_Great Britain_^>a_; _^<a!T16031_Homestead Act_^>a_; _^<a!T16824_Indians, American_^>a_._^<g_
_^<a!T26941_Qianlong_^>a_ (Ch'ien-lung) began his reign as the fourth emperor of China's Manchu dynasty in 1735. Under his rule, _^<a!T6872_China_^>a_ extended its hegemony through large sections of _^<a!T1993_Asia_^>a_, including China proper and several surrounding states such as _^<a!T23377_Nepal_^>a_ and Burma. Qianlong died in 1799, with the Manchu dynasty in a state of decline._^<g_See also: _^<a!T6873_China, history of_^>a_; _^<a!T22970_Myanmar_^>a_; _^<a!T26944_Qing_^>a_._^<g_
The _^<a!T34079_violin_^>a_ evolved from a medieval fiddle used for dances to a work of the highest order of craftsmanship and audio perfection. Around 1700, Antonio Stradivari emerged from his Italian shop to become the foremost maker of violins, producing instruments renowned for their beauty and technical perfection._^<g_See also: _^<a!T1003_Amati, family_^>a_; _^<a!T31154_Stradivari, family_^>a_; _^<a!T31218_stringed instruments_^>a_._^<g_
British captain James _^<a!T8040_Cook_^>a_ was appointed in 1768 by the Royal Society to command a scientific expedition to _^<a!T31697_Tahiti_^>a_ and to seek new lands in the southern _^<a!T24732_Pacific Ocean_^>a_. Over the next three years, Cook surveyed the coasts of _^<a!T23530_New Zealand_^>a_ and claimed possession of the east coast of _^<a!T2259_Australia_^>a_ for _^<a!T11035_England_^>a_. It was the first of Cook's three voyages to the Pacific. He was killed in _^<a!T15259_Hawaii_^>a_ in 1779._^<g_See also: _^<a!T11533_exploration_^>a_; _^<a!T23532_New Zealand, history of_^>a_._^<g_
Between 1600 and 1994, Europe produced the French _^<a!T11063_Enlightenment_^>a_ and the _^<a!T15992_Holocaust_^>a_, the _^<a!T30923_steam engine_^>a_ and a nuclear meltdown. European explorers ranged all over the world to trigger a massive cultural exchange. Yet they brought disease and an appetite for conquest and empire that subjugated societies in _^<a!T396_Africa_^>a_ and the Western Hemisphere. In large measure, European history in this period reflects the historical tides and eddies of civilization itself: relentless material and scientific progress leavened with the horrors of modern warfare and environmental degradation._^<g_By the late-16th century, Europe had shaken off much of its medieval character. Still, the collapse of the old and the onset of the new created a volatile mixture. Between 1618 and 1648, for example, most European nations took part in the _^<a!T32315_Thirty Years' War_^>a_, a bloody affair that began as a dispute between Catholics and Protestants and ended as a thoroughly modern conflict over raw power. Several other conflicts, notably the _^<a!T23093_Napoleonic Wars_^>a_ of the early 19th century, raged to the steady drumbeat of carnage. Ultimately, the 20th-century marriage of war and industrial power dovetailed violently with competition over Europe-based global empires and resources to forge the bloodiest period in European history. Six million Jews were killed in the Holocaust, a systematic slaughter organized by Nazi _^<a!T13521_Germany_^>a_ in the late 1930s and 1940s._^<g_Environmental horrors caused by the 20th-century progeny of the _^<a!T16861_Industrial Revolution_^>a_ triggered widespread movements against degradation of nature. Smog covered London, England, in the early 1960s. In 1986, an explosion at the _^<a!T6751_Chernobyl_^>a_ nuclear reactor in the former Soviet Union became the metaphor for the often-ignored dangers of technological development. The collapse of the Soviet Union uncovered environmental damage on such a huge scale that observers reckoned it would take generations to repair._^<g_All was not grim for Europe, however. Among the giants whose work defined the early years of modern, secular Europe were _^<a!T13092_Galileo Galilei_^>a_ and Sir Isaac _^<a!T23573_Newton_^>a_. The intellectual seeds of the American and French revolutions were planted by French Enlightenment philosophers _^<a!T34198_Voltaire_^>a_, _^<a!T22439_Montesquieu_^>a_ and Jean-Jacques _^<a!T28146_Rousseau_^>a_. The Scotsman Adam _^<a!T30168_Smith_^>a_ contributed the conceptual foundation to free-market economics. In the arts, European composers and painters rose to greatness throughout the 400 years of early modern and modern civilization. Bach and Mozart in music, Matisse and Picasso in art all contributed mightily to the rich cultural landscape of Europe._^<g_At the twilight of the 20th century, Europe's long period of warfare began to fade. The European Community cobbled national self-interest with regional identity to build a new spirit of peace and cooperation. Despite a protracted civil war in the Balkans in the 1990s, Europe generally seemed poised to find lasting peace as the new century loomed._^<g_See also: _^<a!T397_Africa, history of_^>a_; _^<a!T2448_Bach, Johann Sebastian_^>a_; _^<a!T11397_Europe, history of_^>a_; _^<a!T21321_Matisse, Henri_^>a_; _^<a!T22740_Mozart, Wolfgang Amadeus_^>a_; _^<a!T23290_Nazism_^>a_; _^<a!T23960_nuclear reactor_^>a_; _^<a!T25766_Picasso, Pablo_^>a_._^<g_
Iraqi leader Saddam Hussein plunged his country into its second major war in less than a decade when he invaded _^<a!T18771_Kuwait_^>a_ in 1990. The move triggered a military response from a multinational coalition, which ejected _^<a!T17107_Iraq_^>a_ from Kuwait in February 1991. Despite that loss in the _^<a!T25491_Persian Gulf War_^>a_ and the costly stalemate with _^<a!T17103_Iran_^>a_ in the Iran-Iraq War in the 1980s, Hussein maintained his grip on power._^<g_See also: _^<a!T16472_Hussein, Saddam_^>a_; _^<a!T17105_Iran-Iraq War_^>a_; _^<a!T21901_Middle East, history of the_^>a_._^<g_
Mohandas Gandhi, the political and spiritual leader of India's nationalist movement in the 20th century, was assassinated in 1948, a year after his struggle against colonial hegemony culminated in victory. Gandhi's nonviolent strategy held together India's various nationalist factions arrayed against Britain's colonial government._^<g_See also: _^<a!T13171_Gandhi, Mahatma_^>a_; _^<a!T16799_India_^>a_; _^<a!T16800_India, history of_^>a_; _^<a!T24735_pacifism and nonviolent movements_^>a_._^<g_
_^<b_Copyright Information_^>b__^<g_This software is furnished to you under license agreement and may be used only in accordance with the terms of that agreement. No part of this software may be reused, reproduced or transmitted in any form, by any means, electronic or mechanical, including photocopying and recording, for any purpose without the express written consent of Grolier Electronic Publishing, Inc._^<g__^<b__^<i_The 1995 Grolier Multimedia Encyclopedia_^>i_ (TM)_^>b_ Copyright (c) 1995 by Grolier Electronic Publishing, Inc. All rights reserved._^<g_Manufactured in the United States of America._^<g_All text, including Timeline Events and Knowledge Tree (R), and all sounds and images, including Pathmakers, Multimedia Maps, Knowledge Explorer (TM) Essays, and Animations not otherwise cited, copyright (c) 1995 by Grolier, Inc. All rights reserved._^<g_Graphic interface elements, linkages, and access structure of _^<i_The 1995 Grolier Multimedia Encyclopedia_^>i_ (TM) copyright (c) 1995 by Grolier Electronic Publishing, Inc. All rights reserved._^<g_Text retrieval software copyright (c) 1994 by Personal Library Software, Inc. All rights reserved._^<g_Fractal Transform (TM) and the Genuine Fractal Quality (c) logo are trademarks of Iterated Systems, Inc., 1994. All rights reserved._^<g_Maps copyright (c) 1994 by GeoSystems. All rights reserved._^<g__^<i_The 1995 Grolier Multimedia Encyclopedia_^>i_ (TM) contains copyrighted still images licensed from various copyright owners. Credits for individual images appear in their accompanying captions. All rights reserved by the respective copyright owners._^<g_Animal sounds and bird calls copyright (c) 1991 by the Library of Natural Sounds, Cornell Laboratory of Ornithology, Ithaca, NY. All rights reserved._^<g_Martin Luther King, Jr. recording copyright (c) by the Kennedy Library Foundation. All rights reserved._^<g_Various video clips courtesy of and/or copyright (c) by the following parties: Eastman Kodak Company; Harry S. Truman Library; Jet Propulsion Labs; NASA; National Archives; National Broadcasting Corporation, Inc. All rights reserved by the respective parties._^<g_Knowledge Tree (R) is a registered trademark of Grolier Electronic Publishing, Inc. _^<i_The 1995 Grolier Multimedia Encyclopedia_^>i_ (TM) and Knowledge Explorer (TM) are trademarks of Grolier Electronic Publishing, Inc. Other trademarks used are owned by the respective trademark holders._^<g_Views expressed in Pathmakers are not necessarily those of the publisher. They represent the opinions of individual experts and have no bearing on the factual content of the encyclopedia. Pathmakers are presented as a thought-provoking introduction to broad fields of interest--and for unique perspectives on individual achievement and the creative process._^<g__^<i_The 1995 Grolier Multimedia Encyclopedia_^>i_ contains copyrighted materials which are licensed to you, the end user, for your personal use subject to the terms of the accompanying license agreement. You must treat this software and its contents like any other copyrighted material, such as a book or musical recording. Any other use, duplication, or distribution of this product or its contents may violate applicable U.S. or international copyright laws, and may subject you to prosecution under penalty of law. The following are prohibited by law: any theatrical, televised, or public display or performance, including transmission of any material over a computer network; the preparation of any derivative work, including the extraction in whole or in part, of any material without the permission of the copyright owner._^<g__^<b_Copying, Printing, and Saving_^>b_ _^<i_The 1995 Grolier Multimedia Encyclopedia_^>i_ includes Copy, Print, and Save features which allow you to copy, print, and save text and images. These features are provided for your personal use of the product. As an example, you might wish to copy information from a particular article into an electronic research file for later reference, or you might wish to print an image to view at a time when you are away from your computer. However, copyright law does not allow you to copy or print an article or image for commercial publication or use, or for distribution on a computer network. These examples are illustrative only, and are not meant to summarize applicable law._^<g__^<b_Academic Citations_^>b_ Any direct quotations from _^<i_The 1995 Grolier Multimedia Encyclopedia_^>i_ should be accompanied by a footnote or end note containing the following information:_^<g_1. The name of the author of the article, if present in the article. 2. The title of the article. 3. The _^<i_Academic American Encyclopedia (1995 Grolier Multimedia Encyclopedia_^>i_ Version), copyright (c) 1995 Grolier, Inc. Danbury, CT._^<g_
Professor of Geography, University of Helsinki, Helsinki, Finland._^<g_
Professor of Criminal Justice, Saint Xavier College, Chicago._^<g_
Chairman and Wehr Distinguished Professor of Biology, Marquette University, Milwaukee, Wis._^<g_
Chairman of Department and Professor of Portuguese, Georgetown University, Washington, D.C._^<g_
Editor and Publisher of _^<i_Sumo World_^>i_, Nerima-Ku, Tokyo._^<g_
Professor of English, University of Washington, Seattle, Wash._^<g_
Chairman, Department of Fine Arts, Lehigh University, Bethlehem, Pa._^<g_
Professor of Mathematics, University of Maryland, College Park._^<g_
Head, Neurosciences Laboratory, Eye Research Institute, Retina Foundation, Boston._^<g_
Public Affairs Department Manager, DuPont Company, Wilmington, Del._^<g_
Professor of French, New York University, New York City._^<g_
Professor (Acting), Department of Romance Languages, University of Jyvaskyla, Jyvaskyla, Finland._^<g_
Manager, Bevalac Radiobiology-Radiotherapy Program, Division of Biological and Medical Research, Lawrence-Berkeley Laboratory, Berkeley, Calif._^<g_
Chief of Neurology Service, Salt Lake City Veterans Administration Hospital, and Professor of Neurology, University of Utah College of Medicine, Salt Lake City._^<g_
Professor of Geophysics, Geophysical Institute, University of Alaska, Fairbanks._^<g_
Professor of Romance Languages, Harvard University, Cambridge, Mass._^<g_
Professor of Zoology, Arizona State University, Tempe._^<g_
Associate Professor of French, Rice University, Houston, Tex._^<g_
Chairman, Department of Medieval Studies, University of Georgia, Athens._^<g_
Professor of Economics, Emeritus, Rutgers University, New Brunswick, N.J._^<g_
Professor of Human Development, Temple University, Philadelphia._^<g_
Senior Lecturer in Byzantine and Modern Greek, University of Birmingham, Birmingham, England._^<g_
Chairman, Department of English, University of Georgia, Athens._^<g_
Professional Engineer and Consultant, McLean, Va._^<g_
Allen Center for Prenatal Evaluation and Department of Medical Genetics, Children's National Medical Center, Washington, D.C._^<g_
Chairman, Department of Geography, University of Connecticut, Storrs._^<g_
Malaysian Rubber Producers' Research Association, Hertford, England._^<g_
Professor of Astronomy, University of California, Los Angeles._^<g_
Assistant Professor of English, Herbert H. Lehman College, Bronx, N.Y._^<g_
Former Sales Engineer, GTE Sylvania._^<g_
Assistant Professor, Department of History, United States Military Academy, West Point, N.Y._^<g_
Professor of Higher Education, State University of New York, Buffalo._^<g_
Geologist, Amoco Minerals Co., Chicago._^<g_
Associate Director, Gesell Institute of Human Development, New Haven, Conn._^<g_
Chairman, Department of History, Southern Illinois University, Carbondale._^<g_
Director of Communications, International Fabricare Institute, Joliet, Ill._^<g_
Professor of Biology, Whitman College, Walla Walla, Wash._^<g_
Professor of Linguistics, University of Calgary, Calgary, Alberta._^<g_
Professor of Geography, Mankato State University, Mankato, Minn._^<g_
Associate Professor of Political Science, Columbia University, New York City._^<g_
Emeritus Professor of Medicine, Mayo Medical School, Rochester, Minn._^<g_
Assistant Professor, Department of Human Performance and Health Promotion, University of New Orleans, New Orleans, La._^<g_
Professor of Anthropology, Mills College, Oakland, Calif._^<g_
Associate Professor of Biology and Environmental Sciences, University of the Pacific, Stockton, Calif._^<g_
Professor of Classics, University of California, Berkeley._^<g_
Managing Editor, Athena Publishing Co., North Kansas City, Mo._^<g_
Professor of Political Science, California State University, San Diego._^<g_
Research Physicist, Bell Telephone Laboratories, Murray Hill, N.J._^<g_
Professor of Anatomy, Indiana University, School of Medicine, Indianapolis._^<g_
Professional Engineer, F. T. Andrews, Inc., Fullerton, Calif._^<g_
Professor of Romance Languages, Texas Tech University, Lubbock._^<g_
Automotive and Technical Writer._^<g_
Professor Emeritus of Psychology, University of Vermont, Burlington._^<g_
Assistant Public Affairs Director, The Soap and Detergent Association, New York City._^<g_
Professor of Meteorology, Pennsylvania State University, University Park._^<g_
Professor of Musicology, University of Arizona, Tucson._^<g_
Assistant Curator, Museum of Fine Arts, Boston._^<g_
Professor of Bacteriology, Emeritus, University of Southern California, Los Angeles._^<g_
Senior Lecturer in Film, Television Studies, Middlesex Polytechnic, London._^<g_
Neurologist, Montreal Children's Hospital, Montreal._^<g_
Head of the Department of Wildlife and Fisheries, Mississippi State University, Mississippi State._^<g_
Professor of English, University of Cincinnati, Cincinnati, Ohio._^<g_
Chairman, Department of Drama, Tufts University, Medford, Mass._^<g_
Associate Professor, School of Education, Indiana University, Bloomington._^<g_
Assistant Professor, University of Virginia, Charlottesville._^<g_
Ritt Assistant Professor, Columbia University, New York City._^<g_
Professor of Physics and Astrophysics, University of Colorado, Boulder._^<g_
Professor of Anthropology, Adelphi University, Garden City, N.Y._^<g_
Former Lecturer, Birmingham University, Birmingham, England._^<g_
Professor of Political Science, Ohio State University, Columbus._^<g_
Assistant Professor, Rutgers University, New Brunswick, N.J._^<g_
Professor of Geography, Department of Earth Sciences, Montana State University, Bozeman._^<g_
Former Editor of _^<i_The Listener_^>i_._^<g_
Associate Professor, Educational Foundations, University of Florida, Gainesville._^<g_
Professor of Metallurgical Engineering, University of Missouri, Rolla._^<g_
Fellow, Digital Systems Research, RCA Laboratories/David Sarnoff Research Center, Princeton, N.J._^<g_
Professor of Psychology, University of Michigan, Ann Arbor._^<g_
Professor of Archaeology, University College, Cardiff, Wales._^<g_
Associate Professor of Psychology, Rutgers University, New Brunswick, N.J._^<g_
Author of _^<i_Bit by Bit: An Illustrated History of Computers_^>i_._^<g_
Senior Editor, _^<i_Skiing_^>i_ Magazine, New York City._^<g_
Professor of Linguistics and Uralic Studies, Columbia University, New York City._^<g_
Goldwin Smith Professor of Musicology, Cornell University, Ithaca, N.Y._^<g_
Professor of Biology, Rutgers University, New Brunswick, N.J._^<g_
Director, Institute of Material Science, University of Connecticut, Storrs._^<g_
Associate Professor of Church History, Perkins School of Theology, Southern Methodist University, Dallas, Tex._^<g_
Professor of History, University of Minnesota, Minneapolis._^<g_
Associate Professor of Political Science, University of Nebraska, Omaha._^<g_
Associate Professor of History of Science, University of California, Santa Barbara._^<g_
MRC Applied Psychology Unit, Cambridge, England._^<g_
Professor of History, Harvard University, Cambridge, Mass._^<g_
Associate Professorial Lecturer of Sociology, George Washington University, Washington, D.C._^<g_
Senior Research Scientist, Oak Ridge National Laboratory, Oak Ridge, Tenn._^<g_
Professor of English, Butler University, Indianapolis, Ind._^<g_
Director of Music, Trinity Episcopal Church, Fredericksburg, Va._^<g_
Director of Choral Music, Mary Washington College, Fredericksburg, Va._^<g_
Professor of History, Miami University, Oxford, Ohio._^<g_
Professor of Philosophy, Baylor University, Waco, Tex._^<g_
Professor of Biology, College of Arts and Sciences, Grand Valley State Colleges, Allendale, Mich._^<g_
Woodrow Wilson Professor of Literature, Emeritus, Princeton University, Princeton, N.J._^<g_
Senior Paintbox Artist/Digital Editor, Charlex, Inc., New York City._^<g_
Associate Professor of Entomology, North Carolina State University, Raleigh._^<g_
Editor in Chief, _^<i_Publishers Weekly_^>i_, New York City._^<g_
Assistant Professor, School of Theater, Florida State University, Tallahassee._^<g_
Associate Professor of Mathematics, University of Maine, Orono._^<g_
Professor of Political Science, Columbia University, New York City._^<g_
Director and Philecology Curator of Economic Botany, The Institute of Economic Botany, New York Botanical Garden, New York City._^<g_
Director, Wisconsin Center for Film and Theater Research, Madison._^<g_
Professor of Political Science, University of Minnesota, Minneapolis._^<g_
Assistant Clinical Professor of Pharmacy, University of Southern California School of Pharmacy, Los Angeles._^<g_
Composer and Former Program Director, Music, Central Office of Education BIA, Department of Interior._^<g_
Profesora Adjunta Geografia, Universidad Complutense, Madrid._^<g_
President, Spaulding and Slye Construction Co. Inc., Burlington, Mass._^<g_
Rabbi Emeritus, Temple Shaaray Tefila, New York City._^<g_
Professor of Prehistory and Paleontology, University of Berne, Berne, Switzerland._^<g_
Professor of Linguistics, University of Texas, Austin._^<g_
Professor of Psychology, University of Washington, Seattle._^<g_
Journalist, National Catholic News Service, Centreville, Va._^<g_
Professor, Economics and Industrial Relations, University of Wisconsin, Madison._^<g_
Chairman, Division of Preventive Dental Sciences and Section on Pediatric Dentistry, School of Dentistry, University of California, Los Angeles._^<g_
Associate Professor of History, Siena College, Loudonville, N.Y._^<g_
Professor Emeritus, Health Science, University of Wisconsin, Milwaukee._^<g_
Professor of English, University of California, Berkeley._^<g_
Military Historian and Former Infantry Weapons Instructor, Royal Military College of Science, Swindon, England._^<g_
Instructor of Dance, University of Texas, Austin._^<g_
Professor of History, University of Wisconsin, Madison._^<g_
U.S. Army Signal Corps, Author and Editor._^<g_
Professor Emeritus, Graduate School of Education, University of California, Los Angeles._^<g_
President, Physicians Committee for Responsible Medicine, Washington, D.C._^<g_
English Table Tennis Association._^<g_
Director, Children's Zoo, Zoological Society of San Diego, San Diego, Calif._^<g_
Professor of Psychology, University of California, Santa Cruz._^<g_
Professor of Physical Education, Wake Forest University, Winston-Salem, N.C._^<g_
Researcher for the Menil Foundation in the British Museum, London._^<g_
Professor of Geography, University of North Carolina, Chapel Hill._^<g_
Director of Rehabilitation Programs, Chedoke Hospitals, and Professor of Medicine, McMaster University School of Medicine, Hamilton, Ontario._^<g_
Distinguished Professor of Anthropology, Texas A_^<o!E221_M University; Archaeological Director, Institute of Nautical Archaeology, Texas A_^<o!E221_M University, College Station._^<g_
Professor of History of Christianity, Nazarene Theological Seminary, Kansas City, Mo._^<g_
Editor, _^<i_ABC Travel Guides_^>i_._^<g_
Professor of History, Emeritus, Bridgewater State College, Mass._^<g_
Professor of Business Administration, The Colgate Darden Graduate School of Business Administration, University of Virginia, Charlottesville._^<g_
Curatorial Assistant, Edward Clark Streeter Collection of Weights and Measures, Yale Medical Library, New Haven, Conn._^<g_
Professor of Politics and History, Juniata College, Huntingdon, Pa._^<g_
Art Historian._^<g_
Lecturer in the History and Theory of Art, University of Kent, Kent, England._^<g_
Professor of History, Texas A_^<o!E221_M University, College Station._^<g_
Director of Technical Services, The Parker Pen Company, Janesville, Wis._^<g_
Professor of Education, University of California, Irvine._^<g_
Professor of Biology, Montclair State College, Montclair, N.J._^<g_
Fellow, University College, Oxford, England._^<g_
Professor of English, Brooklyn College, City University of New York, Brooklyn, N.Y._^<g_
Austin B. Fletcher Professor of Philosophy, Tufts University, Medford, Mass._^<g_
Associate Professor of History, University of Pennsylvania, Philadelphia._^<g_
Professor of Arabic, University of Oxford, Oxford, England._^<g_
Professor of Anthropology, New York University, New York City._^<g_
Professor of German, Ohio State University, Columbus._^<g_
Professor of History, University of Maryland, Baltimore._^<g_
Associate Professor of Geography, University of Tennessee, Knoxville._^<g_
Assistant Professor of Biology, Middlebury College, Middlebury, Vt._^<g_
Information Officer, Oxford University, Oxford, England._^<g_
Assistant Professor of Art, Wellesley College, Wellesley, Mass._^<g_
Associate Professor of History, Ohio State University, Columbus._^<g_
Professor of Equine Medicine, College of Veterinary Medicine, Colorado State University, Ft. Collins._^<g_
Captain, Royal Navy (ret.)._^<g_
C. B. Sawyer Professor of Engineering and Applied Science and Professor of Physics, Yale University, New Haven, Conn._^<g_
Professor of Chemistry, North Carolina State University, Raleigh._^<g_
Member of the Firm of Blum, Kaplan, Friedman, Silberman and Beran, New York City._^<g_
Professor of English, University of Kansas, Lawrence._^<g_
Professor of Mathematics, Simon Fraser University, Burnaby, British Columbia._^<g_
Professor of Romance Languages, Yale University, New Haven, Conn._^<g_
Professor of English and Comparative Literature, University of Warwick, Coventry, England._^<g_
Former Assistant to the President, The Museum of Broadcasting; Author of _^<i_Look Now, Pay Later: The Rise of Network Broadcasting_^>i_._^<g_
Professor of Physical Geography, University of Lund, Lund, Sweden._^<g_
Office of the Baseball Commissioner, New York City._^<g_
Senior Lecturer of Politics, University of Hull, Hull, England._^<g_
Professor and Director, Social Work in Health Care Program, Massachusetts General Hospital Institute of Health Professions._^<g_
Author of _^<i_Ragtime: A Musical and Cultural History_^>i_._^<g_
Teaching Assistant in Films, Columbia University, New York City._^<g_
Assistant Professor of Art History, State University of New York, Stony Brook._^<g_
Professor of Theatre, Herbert H. Lehman College, Graduate Center of the City University of New York, New York City._^<g_
Foundation Professor of Anthropology, University of Western Australia, Nedlands, Western Australia._^<g_
Professor Emeritus, Library School, University of Minnesota, Minneapolis._^<g_
President, National Foundation for Prevention of Disease, Houston, Tex._^<g_
Professor of Paleontology and Director of Museum of Paleontology, University of California, Berkeley._^<g_
Department of Anthropology, Yale University, New Haven, Conn._^<g_
Associate Professor of Geography, Boston University, Boston._^<g_
Professor of Psychology, Michigan State University, East Lansing._^<g_
Associate Professor of Sociology, California State University, Fresno._^<g_
Assistant Professor of English, University of Wisconsin, Eau Claire._^<g_
Professor of Classics, Boston University, Boston._^<g_
Professor of Geography and Environmental Studies, University of Colorado, Colorado Springs._^<g_
Professor of Physics, Brown University, Providence, R.I._^<g_
James Franck Fellow, University of Chicago, Chicago._^<g_
Associate Curator, Department of Egyptian and Classical Art, The Brooklyn Museum, Brooklyn, N.Y._^<g_
Assistant Professor of Urban Studies, Rutgers University, New Brunswick, N.J._^<g_
Institute for Advanced Study, Princeton, N.J._^<g_
Professor of English, Loyola University, New Orleans, La._^<g_
Professor of Islamic Studies, The Hartford Seminary Foundation, Hartford, Tex._^<g_
Professor of American History, Clark University, Worcester, Mass._^<g_
Professor of History, University of Houston at Clear Lake City, Houston, Tex._^<g_
Author of _^<i_The Complete Book of Thoroughbred Horse Racing_^>i_._^<g_
Professor of Geography, University of North Carolina, Chapel Hill._^<g_
Assistant Professor of History, State University of New York, Albany._^<g_
Associate Professor of Art History, State University of New York, Buffalo._^<g_
Executive Vice-President, Scalamandre, Inc., Long Island City, N.Y._^<g_
Professor of Comparative Studies, Ohio State University, Columbus._^<g_
Associate Professor of Biology, Pennsylvania State University, Delaware County Campus, Media._^<g_
Professor of Geology and Geophysics, University of Connecticut, Storrs._^<g_
Director of Studies, Center for International Security and Arms Control._^<g_
Director, Schola Antiqua, New York City._^<g_
Professor of Pediatrics, School of Medicine, University of Virginia, Charlottesville._^<g_
Visiting Scholar, History of Philosophy of Science Department, Cambridge University, Cambridge, England._^<g_
Associate Professor of Geography, University of Kentucky, Lexington._^<g_
Chairman, Boston Architectural Center, Boston._^<g_
Professor of Physics, Vassar College, Poughkeepsie, N.Y._^<g_
Professor Emeritus in Religion, Columbia University, New York City._^<g_
Senior Physicist, Brookhaven National Laboratory, Upton, N.Y._^<g_
Professor and Chairman, Department of Biomedical History, School of Medicine, University of Washington, Seattle._^<g_
Professor of Anthropology, University of California, Santa Barbara._^<g_
Professor of Art History, University of California, Los Angeles._^<g_
Captain, U.S. Army, United States Military Academy, West Point, N.Y._^<g_
Associate Professor of Classics, New York University, New York City._^<g_
St. Vladimir's Seminary, Tuckahoe, N.Y._^<g_
Professor of French, Emeritus, Yale University, New Haven, Conn._^<g_
Senior Research Engineer, Monsanto Research Corp._^<g_
Professor of Church History, Episcopal Divinity School, Cambridge, Mass._^<g_
Associate Professor of Sociology, Pennsylvania State University, University Park._^<g_
Associate Professor of Anthropology, University of Pennsylvania, Philadelphia._^<g_
Assistant Professor of Art History and Archaeology, Columbia University, New York City._^<g_
Professor of History, University of California, Santa Barbara._^<g_
Professor of Forensic Studies, Indiana University, Bloomington._^<g_
Head, Child and Family Research, National Institute of Child Health and Human Development, Washington, D.C._^<g_
Emeritus Professor of Entomology, Ohio State University, Columbus._^<g_
Former Professor of Education, University of California, Berkeley._^<g_
Assistant Professor of Geography, University of Miami, Miami, Fla._^<g_
Professor of Islamic Studies, McGill University, Montreal._^<g_
Professor of Classics, University of Cincinnati, Cincinnati, Ohio._^<g_
Kennedy Professor of Latin, Emeritus, Princeton University, Princeton, N.J._^<g_
Professor of Journalism, Marquette University, Milwaukee, Wis._^<g_
Associate Professor of Religion, Douglass College, Rutgers University, New Brunswick, N.J._^<g_
Assistant Dean and Lecturer in History, Goucher College, Towson, Md._^<g_
Professor of French, University of Illinois, Urbana._^<g_
Professor of Music, University of North Carolina, Chapel Hill._^<g_
Emeritus Linden Kent Professor of English, University of Virginia, Charlottesville._^<g_
Professor, Department of Political Science, University of Connecticut, Storrs._^<g_
Dean of College of Natural Resources and Professor of Range Management, Utah State University, Logan._^<g_
Power System Consultant._^<g_
Assistant Professor of Geology, Fairleigh Dickinson University, Madison, N.J._^<g_
Professor, Emory University Rollins School of Public Health, Atlanta, Ga._^<g_
Superintendent, Research and Development, Vickers-Armstrong Ltd., Wiltshire, England._^<g_
Shipping Consultant to British Government, London._^<g_
Professor of History, Bryn Mawr College, Bryn Mawr, Pa._^<g_
Chairman, Transportation Institute, Washington, D.C._^<g_
Professor, Asian Theatre, University of Hawaii, Honolulu._^<g_
Director, Business Communications, Dow Chemical Company, Midland, Mich._^<g_
Dean, Ecumenical Institute, St. Mary's Seminary and University, Baltimore, Md._^<g_
Professor of Archaeology, Institute of Archaeology, London University, London._^<g_
Professor of English, Millersville State College, Millersville, Pa._^<g_
Adjunct Associate Professor of Earth and Space Science, State University of New York, Stony Brook._^<g_
Associate Professor of Physiology, University of Chicago, Chicago._^<g_
Professor and Chairman, Department of History of Health Sciences, University of California, San Francisco._^<g_
Professor of Geography, University of Wisconsin, Madison._^<g_
Professor of Near Eastern Studies, University of California, Berkeley._^<g_
Professor of Physics and Astrophysics, University of Colorado, Boulder._^<g_
Wine Auctions Director, Christie's, London._^<g_
Professor-Director of Honors, University of Illinois, Urbana._^<g_
Bill R. Moeckel Professor of Economics and Business, Michigan State University, East Lansing._^<g_
Professor Emeritus, Department of Art and Art History, University of New Mexico, Albuquerque._^<g_
Professor of Microbiology and Nutritional Sciences, Boston University School of Medicine, Boston._^<g_
Lecturer of Romance Languages, Princeton University, Princeton, N.J._^<g_
Yale University School of Drama, New Haven, Conn._^<g_
Director, Schiele Museum, Gastonia, N.C._^<g_
Assistant Professor of Russian, Wayne State University, Detroit._^<g_
Professor of Animal Science, University of Arkansas, Fayetteville._^<g_
Curator of Italian Paintings, National Gallery of Art, Washington, D.C._^<g_
Associate Professor of Industrial Engineering, Auburn University, Auburn, Ala._^<g_
Hockey Editor, The Associated Press, New York City._^<g_
Professor, School of Printing Management and Sciences, Rochester Institute of Technology, Rochester, N.Y._^<g_
Professor of Political Science, Emeritus, Williams College, Williamstown, Mass._^<g_
Professor of Music, Indiana University, Bloomington._^<g_
Assistant Professor of Sociology, Brown University; Research Fellow, Harvard Medical School, Program in Psychiatry and the Law at the Massachusetts Mental Health Center, Boston._^<g_
Professor of Theater, University of California, Riverside._^<g_
Professor of Geography, University of Wyoming, Laramie._^<g_
John Lindsley Professor of Psychology, Harvard University, Cambridge, Mass._^<g_
Professor Emeritus of Chemistry, University of Southern California, Laguna Hills._^<g_
Director, Center for the Study of Popular Culture, Bowling Green State University, Bowling Green, Ohio._^<g_
Executive Director, Community Family Guidance Center, Inc., Red Bank, N.J._^<g_
Professor of Geography, University of North Carolina, Chapel Hill._^<g_
Professor of Economics, Pacific Lutheran University, Tacoma, Wash._^<g_
Professor of Philosophy, Yale University, New Haven, Conn._^<g_
Professor of Geography, Michigan State University, East Lansing._^<g_
Consultant._^<g_
Principal Lecturer in Electrical Engineering, Leeds Polytechnic School of Electrical Engineering, Leeds, England._^<g_
Professor of Business Administration, School of Business Administration, University of California, Berkeley._^<g_
President, The Foundation Center, New York City._^<g_
Major, U.S. Marine Corps._^<g_
Professor of Italian, University of Michigan, Ann Arbor._^<g_
Professor of Physics, Plasma Physics Laboratory, Princeton, N.J._^<g_
Professor of Medicine, Louisiana State University School of Medicine, New Orleans._^<g_
Professor of Musicology, Indiana University, Bloomington._^<g_
Associate Professor of Microbiology and Immunology, University of Oklahoma School of Medicine, Oklahoma City._^<g_
Maritime writer; author of _^<i_Harbor Haven: An Illustrated History of the Port of New York_^>i_._^<g_
Associate Professor of Geography, University of Delaware, Newark._^<g_
Professor of Pediatrics, University of Pennsylvania, Philadelphia._^<g_
Associate Professor, Department of Film, Queen's University, Kingston, Ontario._^<g_
Executive Director, Back To the City, Inc., New York City._^<g_
Lecturer, The New School, New York City._^<g_
Lecturer, Metropolitan Museum of Art, New York City._^<g_
Director, Science and Environmental Reporting Program, New York University, New York City; author of _^<i_Deep Black: Space Espionage and National Security_^>i_._^<g_
Professor Emeritus of Mechanical Engineering, Devon, England._^<g_
Professor and Director of Developmental Psychology Program, State University of New York, Buffalo._^<g_
Associate Professor, Allen R. Hite Art Institute, University of Louisville, Louisville, Ky._^<g_
Professor of Environmental, Population, and Organismic Biology, University of Colorado, Boulder._^<g_
Professor of Political Science and Research Associate, African Studies Center, Boston University, Boston._^<g_
Professor of English, University of Connecticut, Storrs._^<g_
Director, Institute of Museums, History and Secondary Education, North Texas State University, Denton._^<g_
Former President and Professor of Political Science, California State University, Dominguez Hills._^<g_
Assistant Professor of Pediatrics, Tufts University School of Medicine, Boston._^<g_
Professor of Psychiatry and Pharmacology, Yale University School of Medicine, New Haven, Conn._^<g_
Scientist, National Center for Atmospheric Research, Boulder, Colo._^<g_
Professor of History, Ohio University, Athens._^<g_
Director of Development, Household Products, Lever Brothers Company, Edgewater, N.J._^<g_
Senior Lecturer in Chemistry, University of Glasgow, Glasgow, Scotland._^<g_
Research Scientist, Institute for Advanced Study of the Communication Processes of the State University System of Florida, Tallahassee._^<g_
Associate Professor of History, Rensselaer Polytechnic Institute, Troy, N.Y._^<g_
Chairman and Associate Professor, Department of History of Art, Cornell University, Ithaca, N.Y._^<g_
Professor of English, University of Detroit, Detroit._^<g_
Professor of Astronomy, Harvard University, Cambridge, Mass._^<g_
Musicologist, New York City._^<g_
Curator of Amphibians and Reptiles, University of Texas, Arlington._^<g_
Director, Zen-Do Kai Martial Arts Association, Johnstown, N.Y._^<g_
Professor of English, Rutgers University, New Brunswick, N.J._^<g_
Professor of History, Florida State University, Tallahassee._^<g_
Professor of Political Science, University of Maryland, Baltimore._^<g_
Chairman, School of Humanities, Griffith University, Queensland, Australia._^<g_
Professor of Philosophy, Queens College, Flushing, N.Y._^<g_
Mental Health Section, University of Rochester, Rochester, N.Y._^<g_
Professor of Romance Languages, University of Alabama, University._^<g_
Professor of Chemistry, University of Illinois, Chicago Circle._^<g_
Fishery Biologist, U.S. Fish and Wildlife Service, Columbus, Ohio._^<g_
Fellow, Russian Research Center, Harvard University, Cambridge, Mass.; Professor of Political Science, Boston College, Chestnut Hill, Mass._^<g_
Associate Professor of Art History, State University of New York, Purchase._^<g_
Professor of Theater, Cornell University, Ithaca, N.Y._^<g_
Vice-President, Oregon Graduate Center, Beaverton._^<g_
Assistant Professor of Geography, Central Connecticut State University, New Britain._^<g_
Professor of French, Emeritus, University of California, Berkeley._^<g_
Science Writer._^<g_
Professor of Anthropology, University of Toronto, Toronto._^<g_
Professor of Psychology, University of Michigan, Ann Arbor._^<g_
Undersecretary and Administrator, Economics and Statistics Administration, U.S. Department of Commerce, Washington, D.C._^<g_
Director, Center on Child Abuse Prevention Research, National Committee for Prevention of Child Abuse, Chicago._^<g_
Assistant Curator, European Art Department, Detroit Institute of Arts, Detroit._^<g_
Publisher and Editor, _^<i_Performing Arts Journal_^>i_._^<g_
Associate Professor of History, Herbert H. Lehman College, City University of New York, New York City._^<g_
Professor of Art History, Tyler School of Art, Temple University, Ambler, Pa._^<g_
Associate Professor of Physiology, Stanford University, Stanford, Calif._^<g_
Abdulla Fouad Hospital, Dammam, Saudi Arabia._^<g_
Curator of Air Transport, National Air and Space Museum, Smithsonian Institution, Washington, D.C._^<g_
Associate Professor of Church History, Saint Meinrad School of Theology, Saint Meinrad, Ind._^<g_
Assistant Professor of Geography, Ohio State University, Columbus._^<g_
Associate Professor of Computer Science, North Carolina State University, Raleigh._^<g_
Dr. J. G. Davis and Partners, Reading, Berkshire, England._^<g_
International Museum of Photography at George Eastman House, Rochester, N.Y._^<g_
Professor of English, University of Oklahoma, Norman._^<g_
Professor of Hydrology and Water Resources, University of Arizona, Tucson._^<g_
Research Scientist, Massachusetts Institute of Technology, Cambridge._^<g_
Executive Director of the International Swimming Hall of Fame, Fort Lauderdale._^<g_
Chairman, Department of Geography, Saint Mary's University, Halifax, Nova Scotia._^<g_
Author of _^<i_The Hand Tool Book and Carpentry Handbook_^>i_._^<g_
Louis E. Phaneus Professor, Tufts University School of Medicine, Cambridge, Mass._^<g_
Professor of Geophysics, University of Connecticut, Storrs._^<g_
Associate Professor of Political Science, Emory University, Atlanta, Ga._^<g_
Associate Professor of Linguistics, University of Oregon, Eugene._^<g_
Geologist, Environmental Assessment Council, Inc., New Brunswick, N.J._^<g_
Professor of History, Vanderbilt University, Nashville, Tenn._^<g_
Assistant Professor of English, Vassar College, Poughkeepsie, N.Y._^<g_
Professor of Geology, California State University, Long Beach._^<g_
General Manager, _^<i_Europe_^>i_ Magazine._^<g_
Curator, Division of Mineralogy, National Museum of Natural History, Smithsonian Institution, Washington, D.C._^<g_
National Fellow, Jawaharlal Nehru University, New Delhi, India._^<g_
Professor of History, University of Sherbrooke, Sherbrooke, Quebec._^<g_
Professor Emeritus of History, University of California, Berkeley._^<g_
Professor, School of Public Affairs, University of Maryland, College Park._^<g_
Professor of History, Southern Illinois University, Carbondale._^<g_
Worldwatch Institute, Washington, D.C._^<g_
Professor of Communication Arts and Sciences, Queens College of The City University of New York, Queens._^<g_
Professor of Physics, Columbia University and Director of Barnard-Columbia History of Physics Laboratory, New York City._^<g_
Professor of Political Science, Trinity University, San Antonio, Tex._^<g_
Assistant Professor of Anthropology, University of Connecticut, Storrs._^<g_
Professor of Forest Science, Texas A_^<o!E221_M University, College Station._^<g_
Professor of Comparative Literature, University of Massachusetts, Amherst._^<g_
Director, Diamond Headache Clinic, Ltd., and Adjunct Professor of Pharmacology, Chicago Medical School, Chicago._^<g_
Psychopharmacology Research, Instituto de Investigaciones Biomedicas, Universidad de Mexico, Unam, Mexico._^<g_
Supervisory Tea Examiner, U.S. Food and Drug Administration, Brooklyn, N.Y._^<g_
U.S. Naval Observatory, Washington, D.C._^<g_
Professor of Geography, Western Michigan University, Kalamazoo._^<g_
Emeritus Professor of Geography, University of Oregon, Eugene._^<g_
Independent Writer._^<g_
Professor of Geology, Emeritus, Arizona State University, Tempe._^<g_
Chairman, School of History, Leeds University, Leeds, England._^<g_
Associate Professor of Water Resources, Institute of Natural and Environmental Resources, University of New Hampshire, Durham._^<g_
Professor of Linguistics, Georgetown University, Washington, D.C._^<g_
American School of Classical Studies, Athens._^<g_
Professor of Pharmacology and Medicine, Hahnemann University School of Medicine, Philadelphia, Pa._^<g_
Writer and Craftsman._^<g_
Professor of Wildlife Sciences, Texas A_^<o!E221_M University, College Station._^<g_
Professor of Bacteriology and Director of Provincial Laboratory, University of Alberta, Edmonton._^<g_
Charles Hamilton Houston Professor of American Culture, Amherst College, Amherst, Mass._^<g_
Indian Art Consultant, Former Director, Museum of the American Indian._^<g_
Associate Professor of Earth Resources, Colorado State University, Fort Collins._^<g_
Professor of Fine Arts, University of Rochester, Rochester, N.Y._^<g_
Professor, University of Maryland, Baltimore._^<g_
Associate Professor of History, California State University, Hayward._^<g_
Associate Professor of Anatomy, University of Tennessee Center for the Health Sciences, Memphis._^<g_
Science Writer for _^<i_Huntsville Times_^>i_, Huntsville, Ala._^<g_
Professor Emeritus of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh._^<g_
New York State Professor of Glass and Ceramics, Rensselaer Polytechnic Institute, Troy, N.Y._^<g_
Professor of the History of Science and Technology, Stevens Institute of Technology, Hoboken, N.J._^<g_
Lucy Marsh Haskell Professor of Government, Connecticut College, New London, Conn._^<g_
Distinguished Professor of History and Folklore, Indiana University, Bloomington._^<g_
Department of Geology and Geophysics, University of Wisconsin, Madison._^<g_
Associate Curator of Modern Coins, American Numismatic Society, New York City._^<g_
Director, Smell and Taste Center, Hospital of the University of Pennsylvania, Philadelphia._^<g_
Visiting Lecturer, The School of the Art Institute of Chicago._^<g_
Professor of Land Economics, University of Illinois, Urbana-Champaign._^<g_
Professor of Biology, New York University, New York City._^<g_
Assistant Professor, Department of Geological and Geophysical Sciences, Princeton University, Princeton, N.J._^<g_
Professor of Philosophy, St. Louis University, St. Louis, Mo._^<g_
Coordinator, Media and Educational Programs, Visual Studies Workshop, Rochester, N.Y._^<g_
Senior Fellow and Archivist, Hoover Institution on War, Revolution, and Peace, Stanford University, Stanford, Calif._^<g_
Director, National Astronomy and Ionosphere Center, Cornell University, Ithaca, N.Y._^<g_
Former Professor, University of Toronto, Toronto._^<g_
Assistant Dean of the College, and Department of English, Princeton University, Princeton, N.J._^<g_
Lecturer, Professor in History, Princeton University, Princeton, N.J._^<g_
Professor Emeritus of Anthropology, University of Kentucky, Lexington._^<g_
Professor of Geography, McGill University, Montreal._^<g_
Associate Professor of Industrial Engineering, State University of New York, Buffalo._^<g_
Associate Professor, University of New Hampshire, Durham._^<g_
Indiana University, Bloomington._^<g_
Professor of Mathematics, University of Washington, Seattle._^<g_
Lecturer in Modern Chinese, Oxford University, Oxford, England._^<g_
Chief, Pathology, Veterans Affairs Medical Center; Professor of Pathology, Baylor College of Medicine, Waco, Tex._^<g_
Former Professor, United States Air Force Academy, and Former Adjunct Professor, University of Arizona, Tucson._^<g_
Dean, School of Technology, Central Connecticut State College, New Britain._^<g_
Professor of Chemistry, Kent State University, Kent, Ohio._^<g_
Professor of French and Comparative Literature, University of California, Berkeley._^<g_
Senior Economist, Lloyds Bank International, London._^<g_
Professor of East Asian History, Pennsylvania State University, University Park._^<g_
Transport Consultant._^<g_
Professor of Journalism, University of Oregon, Eugene._^<g_
Associate Professor of Legal Studies, The Wharton School, University of Pennsylvania, Philadelphia._^<g_
Professor of Psychology, University of Minnesota, Minneapolis._^<g_
President and Executive Director, Historical Evaluation and Research Organization, Dunn Loring, Va._^<g_
Professor of Geography and Geology Emeritus, University of Wisconsin, Madison, Wis._^<g_
Professor of Geography and of Urban Studies, University of Akron, Akron, Ohio._^<g_
Professor of Otolaryngology, University of Minnesota, Minneapolis._^<g_
Professor of Microbiology, University of Minnesota, Minneapolis._^<g_
Clinical Psychologist, Kaiser Foundation Hospital, Vallejo, Calif._^<g_
Associate Professor, School of Management, University of California, Los Angeles._^<g_
Former Office Manager and Head Bookkeeper, U.S. Building Packages and Restaurant Construction Services._^<g_
Assistant Professor of Geology, Harvard University, Cambridge, Mass._^<g_
Professor of History, University of Michigan, Ann Arbor._^<g_
Professor of Government, Georgetown University, Washington, D.C._^<g_
Assistant Professor of Biology, Brown University, Providence, R.I._^<g_
Former Director of Research, General Electric Co. Limited._^<g_
Associate Professor of Education, Southern Illinois University, Carbondale._^<g_
Director, Live and Learn Education Program, Rosemont, Pa._^<g_
Space Sciences Editor, _^<i_Science News_^>i_._^<g_
Professor of Botany, Eastern Illinois University, Charleston._^<g_
Professor of English, University of Utah, Salt Lake City._^<g_
Landscape Architect, Garrett Eckbo and Associates, San Francisco._^<g_
Senior Scientist, High Altitude Observatory, National Center for Atmospheric Research, Boulder, Colo._^<g_
Professor of Biology, California State University, Chico._^<g_
Former Keeper of Egyptian Antiquities, British Museum, London._^<g_
Associate Professor of English, Carleton University, Ottawa._^<g_
Professor of Physics, Utah State University, Logan._^<g_
Professor of Spanish, Florida State University, Tallahassee._^<g_
Professor and Director, School of Urban and Regional Policy, Rutgers University, New Brunswick, N.J._^<g_
Geologist, U.S. Geological Survey, Menlo Park, Calif._^<g_
Research Assistant, University of Michigan, Ann Arbor._^<g_
Scientific Director, Colorado State University, Fort Collins._^<g_
Professor of Spanish, University of Toronto, Toronto._^<g_
Bishop James W. Bashford Professor of Oriental Studies, University of Southern California, Los Angeles._^<g_
Formerly at Victoria and Albert Museum, London._^<g_
Curator, Delaware Art Museum, Wilmington._^<g_
Professor of Anthropology, Hunter College of the City University of New York, New York City._^<g_
Professor of History, University of Western Ontario, London._^<g_
Associate Curator, Royal Ontario Museum, Toronto._^<g_
Professor of Journalism, University of Minnesota, Minneapolis._^<g_
Professor of Journalism, California State University, Northridge._^<g_
Independent Research Specialist, University of Southern California, Los Angeles._^<g_
Professor of Geography, Mary Washington College, Fredricksburg, Va._^<g_
Staff Member, Los Alamos Scientific Laboratory, University of California, Los Alamos, N.Mex., and Adjunct Professor of Electrical Engineering, Texas Tech University, Lubbock._^<g_
Almuni Distinguished Professor of French, Emeritus, University of North Carolina, Chapel Hill._^<g_
Bensinger Professor of Russian Literature, Yale University, New Haven, Conn._^<g_
Assistant Professor, Department of Criminal Justice, University of Nebraska, Lincoln._^<g_
Professor of Drama, Stanford University, Stanford, Calif._^<g_
Professor of Astronomy, University of Texas, Austin._^<g_
President, United Church of Christ, New York City._^<g_
Professor of Zoology, University of Arkansas, Fayetteville._^<g_
Newton Professor of History, College of William and Mary, Williamsburg, Va._^<g_
Musicologist-Author._^<g_
Assistant Professor of Biology, Central Michigan University, Mount Pleasant._^<g_
Professor of Analytical Chemistry, Seton Hall University, South Orange, N.J._^<g_
Department of History, Brandeis University, Waltham, Mass._^<g_
Associate Professor of New Testament, Southwestern Baptist Theological Seminary, Fort Worth, Tex._^<g_
Professor of Anthropology, University of California, Santa Barbara._^<g_
Professor of Theology, Concordia University, Montreal, Quebec._^<g_
Associate Professor of Plant Sciences, University of Western Ontario, London._^<g_
Information Services Advisor, Paper and Paper Products Industry Training Board._^<g_
Chief Historian, U.S. Air Force Office of Air Force History, Washington, D.C._^<g_
Assistant Professor of the History of Art, Cornell University, Ithaca, N.Y._^<g_
Department of Mechnical Engineering, Virginia Polytechnic Institute and State University, Blacksburg._^<g_
Professor, New Schoof of Liberal Arts, Brooklyn College, City University of New York, New York City._^<g_
Associate Professor of History, University of Minnesota, Minneapolis._^<g_
Professor of Anthropology, State University of New York, Stony Brook._^<g_
Professor of History, Carleton University, Ottawa._^<g_
Terrestrial/Wetlands Ecologist, Environmental Assessment Council, Inc., New Brunswick, N.J._^<g_
Professor of Geology, Ohio State University, Columbus._^<g_
Professor of Sociology and Director, Urban Studies Program, Brooklyn College, City University of New York, Brooklyn._^<g_
National Marine Fisheries Service, Seattle, Wash._^<g_
Music Scholar._^<g_
Professor of Sociology, University of Texas, Austin._^<g_
Professor of Biology, Trinity University, San Antonio, Tex._^<g_
Senior Editor, _^<i_Television Digest_^>i_._^<g_
Professor, Department of Food Science and Technology, University of California, Davis._^<g_
Professor of Physics, Columbia University, New York City._^<g_
Professor of History, Boston University, Boston._^<g_
National Director, B'nai B'rith Career and Counseling Services, Bethesda, Md._^<g_
Professor of Education, Purdue University, Lafayette, Ind._^<g_
Technical Writer and Editor._^<g_
Commonwealth Professor of Political Science, University of Massachusetts, Amherst._^<g_
Associate Professor of Biology, Carleton University, Ottawa._^<g_
Professor of Psychology, Dalhousie University, Halifax, Nova Scotia._^<g_
State Geographer of Florida and Professor of Geography and Director of the Institute of Science and Public Affairs, Florida State University, Tallahassee._^<g_
Professor of Chemistry, University of South Florida, Tampa._^<g_
Curator of Prints and Drawings, Sterling and Francine Clark Art Institute, Williamstown, Mass._^<g_
Professor of Anthropology and Middle Eastern Studies, University of Texas, Austin._^<g_
Adjunct Professor of Chemistry, Kent State University, Kent, Ohio._^<g_
Distinguished Professor of History, Indiana University, Bloomington._^<g_
Professor of English, Boston College, Chestnut Hill, Mass._^<g_
Professor, Griffith University, Nathan, Brisbane, Queensland, Australia._^<g_
Professor of Germanic Languages and Literature, University of Toronto, Toronto._^<g_
Consultant to the Iron and Steel Industry._^<g_
Corpus Christi College, Oxford, England._^<g_
Associate Professor of Art History, Williams College, Williamstown, Mass._^<g_
Snow, Becker and Krass, P.C., New York City._^<g_
Executive Director, Retired, Institute of Electrical and Electronics Engineers, New York City._^<g_
Senior Lecturer in Art History, University of Manchester, Manchester, England._^<g_
Professor of Chemistry, State University College, Brockport, N.Y._^<g_
Curator, National Museum of History and Technology, Smithsonian Institution, Washington, D.C._^<g_
Associate Professor of Biology, University of Wisconsin, River Falls._^<g_
Professor of Geology, Princeton University, Princeton, N.J._^<g_
Freelance Writer._^<g_
Associate Professor of Anatomy, Retired, Chicago Medical School, Chicago._^<g_
Dean, College of Social Sciences, Florida Atlantic University, Boca Raton._^<g_
Professor and Director, Environmental Extension Project, Oklahoma State University, Stillwater._^<g_
Professor of Classical Studies, Monash University, Victoria, Australia._^<g_
Research Scientist, Denver Research Institute, University of Denver, Denver, Colo._^<g_
Professor of Sociology, Fordham University, Bronx, N.Y._^<g_
Assistant Professor of Scandinavian Languages, University of Washington, Seattle._^<g_
Professor, City College and the Graduate School, City University of New York, New York City._^<g_
Dean, School of Humanities, Montclair State College, Upper Montclair, N.J._^<g_
Editor, _^<i_Musical America_^>i_ Magazine._^<g_
Associate Director, USC Paralegal Program, and Adjunct Assistant Professor of Paralegal Studies, University of Southern California Law Center, Los Angeles._^<g_
Professor of Geography, State University of New York, Albany._^<g_
_^<i_World Tennis_^>i_ magazine._^<g_
Professor of History, United States Military Academy, West Point, N.Y._^<g_
Assistant Professor of Economics, University of Oklahoma, Norman._^<g_
Professor of English, Bryant College, Smithfield, R.I._^<g_
Associate Professor of English, University of Delaware, Newark._^<g_
Biologist, Comparative Animal Research Laboratory, University of Tennessee, Oak Ridge._^<g_
Professor of Physics, Michigan State University, East Lansing._^<g_
Assistant Professor of Physiology, Yale University School of Medicine, New Haven, Conn._^<g_
Instructor, Connecticut College, New London._^<g_
Lecturer in Developmental Biology, University of Sussex, Sussex, England._^<g_
Freelance Writer._^<g_
Professor of Classics and History, Brown University, Providence, R.I._^<g_
Professor of Animal Sciences, Purdue University, West Lafayette, Ind._^<g_
Director, Textile and Apparel Research, Philadelphia College of Textiles and Science, Philadelphia._^<g_
Professor of Agricultural Engineering, Cornell University, Ithaca, N.Y._^<g_
Associate Professor of Anthropology, State University of New York, Binghamton._^<g_
Cambridge Research and Instrumentation, Inc., Cambridge, Mass._^<g_
Secretary-Treasurer and Bulletins Editor, Vermont Maple Industry Council, Burlington._^<g_
University of California, Berkeley, Calif._^<g_
Professor of Geography, University of Illinois, Urbana._^<g_
Professor of Physics, University of Utah, Salt Lake City._^<g_
Director, Institute of Women's Studies, Emory University, Atlanta, Ga._^<g_
Principal, James M. Francis & Co., Brooklyn, N.Y._^<g_
Associate American Universities Field Staff, New Delhi, India._^<g_
College of Forest Resources, University of Washington, Seattle._^<g_
President, Franklin Trow Associates Ltd., Toronto._^<g_
President, Watch Tower Bible and Tract Society of Pennsylvania, Brooklyn, N.Y._^<g_
Professor of Chemistry, Iowa State University, Ames._^<g_
Reader in History, University of Bradford, Bradford, England._^<g_
Professor of Art History and Archaeology, Columbia University, New York City._^<g_
Professor of Philosophy, Princeton University, Princeton, N.J._^<g_
Professor of Medicine, Sophie Davis School of Biomedical Education, City College, City University of New York, New York City._^<g_
Dean and Professor of Law, University of Pennsylvania, Philadelphia._^<g_
Associate Professor of Medicine, University of Rochester School of Medicine, Rochester, N.Y._^<g_
Emeritus Professor of Geography, University of Manchester, Manchester, England._^<g_
Professor of English, Indiana University, Indianapolis._^<g_
Research Associate, Geophysics Branch, Goddard Space Flight Center, University of Maryland, Greenbelt._^<g_
Professor of Physics, Brown University, Providence, R.I._^<g_
Professor of Russian Literature, and Head, Department of Slavic Languages and Literatures, University of Illinois, Urbana-Champaign._^<g_
Department of History, University of Maryland, College Park._^<g_
Executive Director, Office of Communication, Christian Church (Disciples of Christ), Indianapolis, Ind._^<g_
Distinguished Teaching Professor of Medicine, State University of New York Health Science Center, Brooklyn._^<g_
Professor of Geology, Rensselaer Polytechnic Institute, Troy, N.Y._^<g_
Professor of Comparative Literature and English, University of Wisconsin, Milwaukee._^<g_
Professor Emeritus of English, Queens College, City University of New York, Queens._^<g_
Associate Professor of History, Youngstown State University, Youngstown, Ohio._^<g_
Assistant Professor of Germanic Languages and Literatures, Yale University, New Haven, Conn._^<g_
Professor of Mathematics, Colorado State University, Fort Collins._^<g_
Professor of Dendrochronology, University of Arizona, Tucson._^<g_
Bell Museum of Natural History, University of Minnesota, Minneapolis._^<g_
Professor of Church History, Princeton Theological Seminary, Princeton, N.J._^<g_
Associate Professor of Animal Sciences, Cook College, New Brunswick, N.J._^<g_
Shailer Mathews Professor of Theology, The Divinity School, University of Chicago, Chicago._^<g_
Former Lecturer in Economics, Harvard University, Cambridge, Mass._^<g_
Professor of Psychology, Virginia Polytechnic Institute and State University, Blacksburg._^<g_
Associate Professor of Biology, University of California, San Diego._^<g_
Professor of German, Tufts University, Medford, Mass._^<g_
Head, Department of Hotel and Catering Studies and Home Economics, Sheffield City Polytechnic, Sheffield, England._^<g_
Professor of Medicine, University of California, San Francisco._^<g_
Author, Playwright._^<g_
Professor of Biological Sciences, University of Illinois, Chicago._^<g_
Department of Geography, Southern Connecticut State University, New Haven._^<g_
Professor of Religion and of Judaica, Boston University, Boston._^<g_
Former Theater Critic, The Associated Press._^<g_
Curator Emeritus of Ornithology, National Museums of Canada, Ottawa._^<g_
Professor of English, University of Cincinnati, Cincinnati, Ohio._^<g_
Attending Staff Psychiatrist, Michael Reese Hospital and Medical Center, Clinical Professor, University of Chicago, and Training and Supervisory Analyst, Chicago Institute for Psychoanalysis, Chicago._^<g_
Director of Mathematics Education, New York University, New York City._^<g_
Assistant Professor of Biology, Temple University, Philadelphia._^<g_
Assistant Professor of Theatre, Illinois State University, Normal._^<g_
Attorney, Speiser & Krause, New York City._^<g_
Professor, City College and the Graduate School, City University of New York, New York City._^<g_
Associate Director, Long Range Planning, National Measurement Laboratory, National Bureau of Standards, Washington, D.C._^<g_
Professor of Political Science, San Francisco State University, San Francisco._^<g_
Assistant Clinical Professor of Psychiatry, University of California, and Staff Psychiatrist, Brentwood Veterans Administration Hospital, Los Angeles._^<g_
Assistant Clinical Professor of Psychiatry, University of California, and Staff Psychiatrist, Brentwood Veterans Administration Hospital, Los Angeles._^<g_
Professor of English, Queens College and the Graduate School, City University of New York, Flushing._^<g_
Attorney, Human Rights Watch, New York City._^<g_
Professor Emeritus of Polar Studies, Ohio State University, Columbus._^<g_
Professor of Physics, Haverford College, Haverford, Pa._^<g_
Assistant Professor of Geography, Southern Connecticut State College, New Haven._^<g_
Deputy Director, Medical Division, Association for Voluntary Surgical Contraception, New York City._^<g_
Associate Professor of Spanish and Portuguese, Yale University, New Haven, Conn._^<g_
Professor of Sociology, State University of New York, Stony Brook._^<g_
Professor, Department of Civil and Environmental Engineering, Polytechnical Institute of New York, Brooklyn._^<g_
Professor Emeritus of Political Science, Southern Illinois University, Edwardsville._^<g_
Professor of French and Comparative Literature, Claremont Colleges, Claremont, Calif._^<g_
Assistant Professor of Fine Arts, Trinity College, Hartford, Conn._^<g_
Associate Professor and Director, Emergency Technology Program, University of Texas Health Center, San Antonio._^<g_
Emory University, School of Medicine, Atlanta, Georgia._^<g_
Associate Professor of Veterinary Preventive Medicine, Ohio State University, Columbus._^<g_
Professor of History, University of Richmond, Richmond, Va._^<g_
Department of Middle East Languages and Cultures, Columbia University, New York City._^<g_
Assistant Professor of Drama, New York University, New York City._^<g_
Researcher, Museum of Modern Art, New York City._^<g_
Professor of Chemistry, Oklahoma State University, Stillwater._^<g_
Adjunct Associate Professor of Pharmacology, University of Kentucky College of Medicine, Lexington._^<g_
Assistant Professor of Philosophy, Albright College, Reading, Pa._^<g_
Professor of Old Testament and of Biblical Theology and Ethics, Graduate Theological Union, Berkeley, Calif._^<g_
Professor of Biology, Utica College of Syracuse University, Utica, N.Y._^<g_
Professor of History, University of Texas, Austin._^<g_
Professor of Art History, Sarah Lawrence College, Bronxville, N.Y._^<g_
Research Geologist, U.S. Army Cold Regions, Research and Engineering Laboratory, Hanover, N.H._^<g_
Professor of Fine Arts, Harvard University, Cambridge, Mass._^<g_
Professor of Anthropology, University of California, Berkeley._^<g_
Professor of History, University of California, Santa Barbara._^<g_
Professor of Systematic Theology, The Catholic University of America, Washington, D.C._^<g_
Professor Emeritus of Natural Science and History of Science, University of Minnesota, Minneapolis._^<g_
Former Editor and Publisher, _^<i_Soundings_^>i_._^<g_
Professor of English, Indiana University, Bloomington._^<g_
Assistant Professor of Celtic Languages and Literatures, Harvard University, Cambridge, Mass._^<g_
Research Professor of Social Theory in Government, New York University, New York City._^<g_
Associate Professor of History, U.S. Naval Academy, Annapolis, Md._^<g_
President, SEASUN Power Systems, Inc., Alexandria, Va._^<g_
Professor of German, University of Illinois, Urbana._^<g_
Professor of Communication Studies, Northwestern University, Evanston, Ill._^<g_
Associate Director, Ukrainian Research Institute, Harvard University, Cambridge, Mass._^<g_
Professor of English, University of Delaware, Newark._^<g_
Professor of the History of Science and Technology, Imperial College, London._^<g_
Professor of Horticulture, Iowa State University, Ames._^<g_
Art Historian and Author, _^<i_Dictionary of Subjects and Symbols in Art_^>i_._^<g_
Professor of Geography and Chairman, Department of Social Sciences, Louisiana State University, Shreveport._^<g_
Professor of History and Geography, University of Rochester, Rochester, N.Y._^<g_
Professor of Geological Sciences, University of Birmingham, Birmingham, England._^<g_
Associate Professor, University of Maryland, College Park._^<g_
Film Buyer, ITV Network of Great Britain, and Author, _^<i_The Filmgoers Companion, Halliwell's Filmguide_^>i_._^<g_
Icelandic Poet, Editor, and Translator; Coeditor of _^<i_Icelandic Folk and Fairy Tales_^>i_._^<g_
Professor of Near Eastern Studies, Princeton University, Princeton, N.J._^<g_
Professor of English, University of Southern California, University Park, Los Angeles._^<g_
Department of Chemistry, Indiana State University, Terre Haute._^<g_
Dean, School of Information Science and Policy, The University at Albany, State University of New York, and Former Chairman, Reference and Subscription Books Reviews Committee, American Library Association._^<g_
Associate Professor of Journalism, University of Oregon, Eugene._^<g_
Special Assistant to the Director, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Md._^<g_
Professor of History, Ohio University, Athens._^<g_
Editor, _^<i_Canadian Churchman_^>i_._^<g_
National Research Council Resident Research Associate, Jet Propulsion Laboratory, Pasadena, Calif._^<g_
Professor of Psychology, University of Tennessee, Knoxville._^<g_
Professor of Biology, California State University, Fullerton._^<g_
Packaging Consultant, Formerly with Hoffmann-La Roche, Inc., Nutley, N.J._^<g_
Professor of Philosophy, University of Vermont, Burlington._^<g_
Professor of Nuclear Engineering, Massachusetts Institute of Technology, Cambridge._^<g_
Professor of Geology, Stanford University, Stanford, Calif._^<g_
Professor of Political Science, Whitman College, Walla Walla, Wash._^<g_
Abercromby Professor of Archaeology, University of Edinburgh, Edinburgh._^<g_
Secretary, The Thoreau Society, Geneseo, N.Y._^<g_
Professor of Psychology, University of British Columbia, Vancouver._^<g_
Lecturer in Anglo-Irish Literature, University College, Dublin._^<g_
Professor Emeritus, Department of Geography, University of Maryland, College Park._^<g_
Director, Centre for Research in the New Literatures in English (CRNLE), Flinders University, Bedford Park, South Australia, Australia._^<g_
Professor of Literature, Sarah Lawrence College, Bronxville, N.Y.; College Professor of the Arts, Trinity College, Hartford, Conn.; Adjunct Professor of Art History, Cooper Union for the Advancement of Science and Art, New York City; and Visiting Professor of Dance History, School of the Arts, New York City._^<g_
Author of _^<i_Hydroponics: Growing without Soil_^>i_._^<g_
Professor of Physics and Astronomy, University of Tennessee, Knoxville._^<g_
Associate Professor of Library and Information Science, St. John's University, Jamaica, N.Y._^<g_
Professor, Michigan State University, East Lansing._^<g_
Eminent Professor of Philosophy, Old Dominion University, Norfolk, Va._^<g_
Distinguished Professor of History, University of Miami, Coral Gables, Fla._^<g_
Brearley School, New York City._^<g_
Professor of Anthropology and Director, Center for Southeast Asian Studies, Northern Illinois University, De Kalb._^<g_
Associate Professor of English, University of British Columbia, Vancouver._^<g_
Professor Emeritus, College of Environmental Science and Forestry, State University of New York, Syracuse._^<g_
Professor Emeritus, Journalism and Mass Media, Rutgers University, New Brunswick, N.J._^<g_
Professor of Geology and Geography, University of Massachusetts, Amherst._^<g_
Associate Professor of Geography, Georgia State University, Atlanta._^<g_
Professor of History, Hunter College, City University of New York, New York City._^<g_
Professor of Religious Studies, Stanford University, Stanford, Calif._^<g_
Chair, Department of Social and Behavioral Sciences, University of New England, Biddeford, Maine._^<g_
Assistant Professor of English, Boston College, Chestnut Hill, Mass._^<g_
Professor of American History, Pennsylvania State University, University Park._^<g_
Department of Geological Sciences, University of Tennessee, Knoxville._^<g_
Professor of Internal Medicine and Pathology, School of Medicine, University of California, Davis._^<g_
Professor of Geography, University of Dublin, Dublin._^<g_
Assistant Professor of History, University of Rochester, Rochester, N.Y._^<g_
Professor of Biology and Entomology, Utah State University, Logan._^<g_
Director of the Institute of Scottish Studies, Old Dominion University, Norfolk, Va._^<g_
Professor of Earth Sciences, University of Manitoba, Winnipeg._^<g_
Assistant Professor of Fine Arts, Harvard University, Cambridge, Mass._^<g_
Christian Minister, Former Editor of the _^<i_Christian Standard_^>i_._^<g_
Associate Professor of Organ, Westminster Choir College, Princeton, N.J._^<g_
Associate Professor of Social Sciences, Roosevelt University, Chicago._^<g_
Distinguished Professor and Director of Agriculture, Iowa State University, Ames._^<g_
Professor of Geography, Hilo College, University of Hawaii, Hilo._^<g_
Professor of Philosophy and Dean, School of Humanities, University of Alabama, Birmingham._^<g_
Professor of History of Science and Technology, University of California, Berkeley._^<g_
Associate Professor of Psychology, De Paul University, Chicago._^<g_
Clinical Psychologist, Private Practice._^<g_
Assistant Professor of Slavic Languages, University of California, Los Angeles._^<g_
Professor, Lesley College Graduate School of Education, Cambridge, Mass._^<g_
Director, Research and Development, Diamond Crystal Salt Co., Saint Clair, Mich._^<g_
Professor of German and Comparative Literature, State University of New York, Buffalo._^<g_
Executive Director, The Development Group for Alternative Policies, Washington, D.C._^<g_
Dean of Instruction and Professor of History, Allegheny College, Meadville, Pa._^<g_
Professor of History, Wheaton College, Norton, Mass._^<g_
Professor, Department of Anthropology, University of North Carolina, Greensboro._^<g_
Assistant Professor of English, Arizona State University, Tempe._^<g_
Visiting Member, Institute for Advanced Study, Princeton, N.J._^<g_
Associate Professor of Greek and Latin, University of Michigan, Ann Arbor._^<g_
Assistant Professor of Anthropology, Cornell University, Ithaca, N.Y._^<g_
Professor of Geography, University of Arizona, Tempe._^<g_
Chairman, Department of Ophthalmology, Albert Einstein College of Medicine, Bronx, N.Y._^<g_
Professor of History, University of Iowa, Iowa City._^<g_
Assistant Professor of Medicine, University of Southern California, Los Angeles._^<g_
Department of Dairy and Animal Science, Pennsylvania State University, University Park._^<g_
Biological Consultant, Henry and Associates Co., Waskesiu, Saskatchewan._^<g_
Editor, _^<i_Auto Racing Digest_^>i_, Century Publishing Co., Evanston, Ill._^<g_
Professor of German and Comparative Literature, University of Maryland, College Park._^<g_
Co-Director of Folk Dance House and Folk Dance Consultant for Dance Division of Performing Arts Library, New York City._^<g_
Associate Professor of Zoology, Rutgers University, New Brunswick, N.J._^<g_
Distinguished Professor of Education;/Associate Dean for Graduate Programs, Research and Technology, College of Education, Pennsylvania State University, University Park._^<g_
Adjunct Professor of Anthropology, State University of New York College of Technology, Utica-Rome._^<g_
Professor of Agricultural Economics, Pennsylvania State University, University Park._^<g_
Contributing and Consulting Editor, _^<i_Modern Photography_^>i_._^<g_
Associate Professor, Hudson Valley Community College, Troy, N.Y._^<g_
Rutgers University, New Brunswick, N.J._^<g_
Professor of Hebrew, University of California, Santa Barbara._^<g_
Associate Professor of Psychology, State University of New York, Albany._^<g_
Curator of Decorative Arts after 1700, Philadelphia Museum of Art, Philadelphia._^<g_
Art Historian._^<g_
Geologist, U.S. Geological Survey, Menlo Park, Calif._^<g_
Professor of History, University of North Carolina, Chapel Hill._^<g_
Associate Professor of Biology, West Texas State University, Canyon._^<g_
Associate, American Language Program, Columbia University, New York City._^<g_
Assistant Professor of Geography, Southern Illinois University, Carbondale._^<g_
Distinguished Professor of History, University of Wisconsin, Milwaukee._^<g_
Professor of History, Florida State University, Tallahassee._^<g_
Publisher and Editor, _^<i_Women's International Network News_^>i_._^<g_
Associate Professor of Astronomy, Cornell University, Ithaca, N.Y._^<g_
Associate Professor of Geography, University of Nevada, Reno._^<g_
Assistant Professor of History, Harvey Mudd College, Claremont, Calif._^<g_
Professor of Chemistry, University of Texas, San Antonio._^<g_
Former Assistant Professor of Music, Kent State University, Kent, Ohio._^<g_
The United Church of Canada, Ottawa._^<g_
Assistant Professor of Fine Arts, Boston College, Chestnut Hill, Mass._^<g_
Research Professor of Musicology, University of Georgia, Athens._^<g_
Contributing Editor, _^<i_Performing Arts Journal_^>i_._^<g_
Department of Biology, University of Southampton, Southampton, England._^<g_
Professor of Comparative Education, Teachers College, Columbia University, New York City._^<g_
Professor of Political Science, Florida Atlantic University, Boca Raton._^<g_
Associate Professor of Journalism, Michigan State University, East Lansing._^<g_
Associate Professor of Linguistics and Asian Studies, Cornell University, Ithaca, N.Y._^<g_
Acting Maryland State Climatologist, University of Maryland, College Park._^<g_
Professor of Anthropology, and Family and Community Medicine, University of Utah, Salt Lake City._^<g_
Professor and Extension Horticulturalist, Michigan State University, East Lansing._^<g_
Geologist, Formerly with the U.S. Geological Survey._^<g_
Professor of Anthropology and Health Education, Pennsylvania State University, University Park._^<g_
Instructor-Trainer and Chairman, Chapter First Aid, American Red Cross, Princeton, N.J._^<g_
Deputy Director, Middle East Project, Center for Strategic and International Studies, Georgetown University, Washington, D.C._^<g_
Consultant to the Iron and Steel Industry._^<g_
Professor Emeritus of Mineralogy, Harvard University, Cambridge, Mass._^<g_
Professor of Political Science, Cleveland State University, Cleveland, Ohio._^<g_
Professor of Music, University of Akron, Akron, Ohio._^<g_
Professor of Forest Ecology, Pennsylvania State University, University Park._^<g_
Department of Psychology, Illinois Institute of Technology, Chicago._^<g_
Professor of Law, Rutgers-The State University of New Jersey-School of Law, Newark._^<g_
Professor of Psychology, University of Oregon, Eugene._^<g_
Associate Professor of Journalism and Mass Communication, University of Georgia, Athens._^<g_
Department of Geography, Auburn University, Auburn, Ala._^<g_
Chief, Division of International Fisheries Development and Services, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce, Washington, D.C._^<g_
Professor of History, State University of New York, Buffalo._^<g_
Professor of Chemistry, Integrated Liberal Studies and History of Science, University of Wisconsin, Madison._^<g_
Department of Geography, Middlebury College, Middlebury, Vt._^<g_
Assistant Professor of Political Science, William Paterson College of New Jersey, Wayne, N.J._^<g_
Research Astronomer, Monterey Institute for Research in Astronomy, Monterey, Calif._^<g_
Chairman, Department of History of Art, University of Aberdeen, Old Aberdeen, Scotland._^<g_
Emeritus Professor of Psychology, University of Pennsylvania, Philadelphia._^<g_
Former Associate Professor, Kean College of New Jersey, Union, N.J._^<g_
Landscape Architect, U.S. Department of Housing and Urban Development, Washington, D.C._^<g_
Charles Dyer Norton Professor of Regional Planning, Emeritus, Harvard University, Cambridge, Mass._^<g_
Professor of Music, University of Kentucky, Lexington._^<g_
Professor of Political Science, State University of New York, Stony Brook._^<g_
Professor Emeritus of History, University of Virginia, Charlottesville._^<g_
Assistant Professor of History, Temple University, Philadelphia._^<g_
Food Historian._^<g_
Professor of Geography and Education, Adjunct Professor of Anthropology, Michigan State University, East Lansing._^<g_
Supervisory Research Chemist, U.S. Department of Agriculture, Beltsville, Md._^<g_
Professor of Art History, Fordham University, Bronx, N.Y._^<g_
Former Research Geologist, U.S. Geological Survey._^<g_
Professor of Horticulture, Purdue University, West Lafayette, Ind._^<g_
Professor of Physiology, University of Saskatchewan, Saskatoon._^<g_
Associate Professor of Swedish, North Park College, Chicago._^<g_
Assistant Director, Hubbs-Sea World Research Institute, San Diego, Calif._^<g_
Emeritus Professor of Mechanical Engineering, Northwestern University, Evanston, Ill._^<g_
Assistant Professor of Political Science, Stockton State College, Pomona, N.J._^<g_
Professor of English, Indiana University, Bloomington._^<g_
Professor and Head, Department of Microbiology, University of Arizona, Tucson._^<g_
Professor of New Testament Interpretation, Garrett-Evangelica Theological Seminary, Evanston, Ill._^<g_
So-Cal Safety Associates, Reston, Va._^<g_
Professor, Department of Psychological and Social Foundations, University of South Florida, Tampa._^<g_
Institute of Human Origins, Berkeley, Calif._^<g_
Professor of Biology, Queens College, City University of New York, Flushing._^<g_
Professor, Department of Population Biology, Australian National University, Canberra._^<g_
General Secretary, Church of the Nazarene, Kansas City, Mo._^<g_
Associate Professor, College of Technology, University of Houston, Houston, Tex._^<g_
Director, Asian Studies, New York University, New York City._^<g_
Associate Professor of Music, University of Virginia, Charlottesville._^<g_
Professor of Law, University of Southern California Law Center, Los Angeles._^<g_
Associate Professor of Geography, University of North Dakota, Grand Forks._^<g_
Professor of French, University of Kansas, Lawrence._^<g_
Professor of Physiology, University of Texas Medical School, Houston._^<g_
Professor of English, Mount Holyoke College, South Hadley, Mass._^<g_
Senior Organic Chemist, Eli Lilly and Company, Indianapolis, Ind._^<g_
Dean and Professor of New Testament, Emeritus, The Church Divinity School of the Pacific, Berkeley, Calif._^<g_
Bates Professor of Diseases of Women and Children, Department of Obstetrics and Gynecology, University of Michigan Medical Center, Ann Arbor._^<g_
Associate Professor, Graduate School of Journalism, Columbia University, New York City._^<g_
Professor, Department of Classical and Oriental Studies, Brandeis University, Waltham, Mass._^<g_
Former Director, National Air and Space Museum, Smithsonian Institution, Washington, D.C._^<g_
Freelance Editor and Translator._^<g_
Professor of Anthropology, New York University, New York City. andrew D. Jones P.E Head, Civil Engineering, California Polytechnic State University, San Luis Obispo._^<g_
Head, Civil Engineering, California Polytechnic State University, San Luis Obispo._^<g_
Professor of Economics, La Trobe University, Melbourne, Australia._^<g_
Associate Professor of Art History, Trenton State College, Trenton, N.J._^<g_
Vice-Chancellor and Dean of the Graduate School, University of North Carolina, Chapel Hill._^<g_
Professor of Medicine and Pediatrics, and Director, Division of Medical Genetics, University of California, La Jolla._^<g_
Assistant Professor of Geography, University of Texas, San Antonio._^<g_
Regents' Professor, Emeritus, University of Minnesota, Minneapolis._^<g_
Professor of Geography, University of Toronto, Toronto._^<g_
Professor of English, University of California, Berkeley._^<g_
Assistant Publisher, _^<i_Track & Field News_^>i_._^<g_
Assistant Professor of Anesthesia, University of Pennsylvania School of Medicine, Philadelphia._^<g_
Ashbel Smith Professor, Linguistics and Germanic Languages, University of Texas, Austin._^<g_
Professor of History, University of Minnesota, Minneapolis._^<g_
Emeritus Professor of Biochemistry, University of the Pacific, Stockton, Calif._^<g_
Associate Professor of Geography, University of Kentucky, Lexington._^<g_
Professor of English, Purdue University, West Lafayette, Ind._^<g_
Director, Wine/Beverage Program, Forest Hills, N.Y._^<g_
Editor, _^<i_Firm Foundation_^>i_._^<g_
Department of Biology, McGill University, Montreal._^<g_
Professor of Dermatology, Yale University School of Medicine, New Haven, Conn._^<g_
Professor of Dermatology, Yale University School of Medicine, New Haven, Conn._^<g_
Professor of Romance Languages, Emeritus, Pennsylvania State University, University Park._^<g_
Assistant Professor of History, Hiram College, Hiram, Ohio._^<g_
Professor of Physics, University of Rhode Island, Kingston._^<g_
Panel Lecturer, Victoria & Albert Museum, London._^<g_
Director, The Federal Judicial Center, and Professor of Law, University of Pennsylvania, Philadelphia._^<g_
Professor of English, Livingston College, Rutgers University, New Brunswick, N.J._^<g_
Professor of Political Science, University of Southwestern Louisiana, Lafayette._^<g_
Professor of Biology, City College, City University of New York, New York City._^<g_
Professor of Law, University of Texas Law School, Austin._^<g_
Research Professor of Economics and Director, Center for Social Policy Studies, George Washington University, Washington, D.C._^<g_
Professor of Art History, Columbia University, New York City._^<g_
Professor of History, University of the District of Columbia, Washington, D.C._^<g_
Professor of Geography, Emeritus, Boston University, Boston._^<g_
Defense and Arms Control Studies Program, Massachusetts Institute of Technology, Cambridge._^<g_
Department of Biology as Applied to Medicine, Middlesex Hospital Medical School, London._^<g_
Aviation Author, Illustrator, and Photographer._^<g_
Freelance Science Writer._^<g_
Assistant Professor of Black American Studies, University of Delaware, Newark._^<g_
Professor of Computer Science, Oregon State University, Corvallis._^<g_
Instructor in Medical Psychology, The Johns Hopkins University School of Medicine and Hospital, Baftimore, Md._^<g_
Gottesman Professor of Cinema Studies, New York University, New York City._^<g_
Department of Near Eastern Languages and Civilizations, Emerita, Harvard University, Cambridge, Mass._^<g_
Professor of Communication Arts, University of Wisconsin, Madison._^<g_
Field Research & Development Specialist, Dow Chemical, USA._^<g_
Former News Editor and Stamp News Columnist, _^<i_New York Times_^>i_._^<g_
Professor, Monmouth College, West Long Branch, N.J._^<g_
Russian Research Center, Harvard University, Cambridge, Mass.; Professor of Political Science, Wellesley College, Wellesley, Mass._^<g_
Managing Editor, _^<i_Video Week_^>i_._^<g_
Author of _^<i_Backyard Games_^>i_._^<g_
Professor Emeritus, Engineering Technology, Western Michigan University, Kalamazoo._^<g_
Professor of History, University of Oregon, Eugene._^<g_
Professor of African and English Literature, University of Texas, Austin._^<g_
Brownell-Jarvis Professor of Natural Philosophy and Physics, Trinity College, Hartford, Conn._^<g_
AT_^<o!E221_T Bell Laboratories, Murray Hill, N.J._^<g_
Curator of Asian Art and Keeper of the Ukiyo-e Center, Honolulu Academy of Arts, Honolulu._^<g_
University Professor, Portland State University, Portland, Oreg._^<g_
Professor of Chemistry, Columbia University, New York City._^<g_
Professor Emeritus, City University of New York, New York City._^<g_
Freelance Sports Writer._^<g_
Fellow of Wolfson College, University of Cambridge, and President, Royal Society of Miniature Painters, Sculptors, and Gravers, and Chairman of the Board of Governors, Federation of British Artists, Cambridge, England._^<g_
Assistant Professor of History, Massachusetts Institute of Technology, Cambridge._^<g_
Associate Professor of Geography, West Virginia University, Morgantown._^<g_
Associate Professor of Anthropology, and Chairman, Department of Sociology and Anthropology, Occidental College, Los Angeles._^<g_
Assistant Professor of Special Education, University of Virginia, Charlottesville._^<g_
Graduate Center of the City University of New York, New York City._^<g_
Associate Professor of Architecture, Pratt Institute, Brooklyn, N.Y._^<g_
Professor and Chairperson, Department of Art History and Criticism, The School of the Art Institute of Chicago._^<g_
Professor of Geography, University of California, Los Angeles._^<g_
Aerospace Engineer, Rockwell International, Satellite Systems Division, Seal Beach, Calif._^<g_
Librarian, Archbold Biological Station, Lake Placid, Fla._^<g_
Queens College of CUNY, Flushing, and Lamont-Doherty Geological Observatory, Palisades, N.Y._^<g_
Professor of Theatre, Graduate Center of the City University of New York, New York City._^<g_
William Rand Kenan, Jr., Professor of History of Religions, University of North Carolina, Chapel Hill, and Professor of History of Religions, Duke University, Durham, N.C._^<g_
Technical Writer._^<g_
Consultant Physiologist, National Heart Hospital, London._^<g_
Professor of Music, University of Kentucky, Lexington._^<g_
Professor of Vegetable Crops, University of California, Davis._^<g_
Professor and Consultant._^<g_
Acting Instructor, Department of History of Art, Yale University, New Haven, Conn._^<g_
Professor and Associate Head of the Department of Biological Sciences, Purdue University, West Lafayette, Ind._^<g_
Deputy Keeper, Indian Department, Victoria & Albert Museum, London._^<g_
Professor and Chairman, Department of Otolaryngology, Jefferson Medical College, Philadelphia, Pa._^<g_
Department of History, University of Chicago, Chicago._^<g_
Professor of Zoology and Genetics, University of North Carolina, Chapel Hill._^<g_
Professor of Classics, The Johns Hopkins University, Baltimore, Md._^<g_
Exhibit Curator and Associate Director, Exhibit Museum, University of Michigan, Ann Arbor._^<g_
Associate Professor of Spanish, University of California, Los Angeles._^<g_
Professor of Philosophy, University of North Carolina, Chapel Hill._^<g_
Professor of History, Duquesne University, Pittsburgh, Pa._^<g_
Director of Consumer Relations, International Fabricare Institute, Silver Spring, Md._^<g_
Professor of Geography, College of Arts and Sciences, University of Alaska, Fairbanks._^<g_
Chairman, Department of Canon Law, Catholic University of America, Washington, D.C._^<g_
Senior Research Analyst, Washington International Energy Group, Washington, D.C._^<g_
Director, National Engineering Laboratory, National Bureau of Standards, Washington, D.C._^<g_
Information Officer, City of Philadelphia, Philadelphia._^<g_
Former Naturalist, Freshwater Biological Association, Cambria, England._^<g_
Associate Professor of Criminal Justice, University of Illinois, Chicago._^<g_
Chairman, Theology Department, University of Notre Dame, Notre Dame, Ind._^<g_
African Studies Center, Boston University, Boston, Mass._^<g_
Associate Professor of English, Iowa State University, Ames._^<g_
Director of Psychological Services, Almeda Clinic, Houston, Tex._^<g_
Professor of Biology, University of Arizona, Tucson._^<g_
Associate Professor of Geography, University of Kansas, Lawrence._^<g_
Associate Professor of Zoology, Colorado State University, Ft. Collins._^<g_
Assistant Professor of the History of Science, Stevens Institute of Technology, Hoboken, N.J._^<g_
Professor of Economics, University of Nebraska, Lincoln._^<g_
Professor, Washington State University, Pullman._^<g_
Associate Professor, Emeritus, Tulane University, New Orleans, La._^<g_
Associate Editor, _^<i_Backpacking Journal_^>i_ and _^<i_Camping Journal_^>i_._^<g_
Associate Director for Measurement Services, National Measurement Laboratory, National Bureau of Standards, Washington, D.C._^<g_
Formerly Senior Specialist in Science and Technology, Science Policy Research Division, Congressional Research Service, Library of Congress, Washington, D.C._^<g_
Assistant Professor, School of Education, University of Virginia, Charlottesville._^<g_
Associate Professor of Microbiology, University of Texas Medical Branch, Galveston._^<g_
Professor of History, University of Alabama, University._^<g_
Professor of History, Northeastern Illinois University, Chicago._^<g_
Foreign Service Officer (ret.)._^<g_
Curator, Museum of Scottish Tartans, Comrie, Scotland._^<g_
Former Writer-Producer, Sports, WCBS Radio, New York City._^<g_
Professor of History, University of Massachusetts, Amherst._^<g_
Associate Professor of German, University of Illinois, Urbana._^<g_
Consultant, lecturer of self-defense and co-author of _^<i_Self-Defense & Assault Prevention for Girls & Women_^>i_._^<g_
Professor Emeritus of Anthropology, University of Illinois, Urbana._^<g_
Professor of Psychology, Yale University, New Haven, Conn._^<g_
Associate Professor of English, Georgia State University, Atlanta._^<g_
Michael P. Grace Professor of Medieval Studies, and Director, The Medieval Institute, University of Notre Dame, Notre Dame, Ind._^<g_
Captain, Royal Navy (ret.), Kent, England._^<g_
Professor of Psychology, Indiana University, South Bend._^<g_
Professor of Geography, San Jose State University, San Jose, Calif._^<g_
Associate Professor of Genetics, Cornell University, Ithaca, N.Y._^<g_
Engineer, Environmental Sciences Corp., Chapel Hill, N.C._^<g_
Professor of Agronomy, Pennsylvania State University, University Park._^<g_
Assistant Professor of Government, Colby College, Waterville, Maine._^<g_
Former Professor of Church History, Union Theological Seminary in Virginia, Richmond._^<g_
Professor of Geography, University of California, Los Angeles._^<g_
Lecturer in Modern Greek Language and Literature, University of London, King's College, London._^<g_
Professor, Department of Education, University of Waikato, Hamilton, New Zealand._^<g_
Author of _^<i_The Wolf Children_^>i_._^<g_
Professor of Psychology, University of Victoria, Victoria, British Columbia._^<g_
Professor of Political Science, Miami University, Oxford, Ohio._^<g_
Political Advisor, _^<i_Daily Express_^>i_, London._^<g_
Energy Study Group, New University of Ulster, Coleraine, Northern Ireland._^<g_
Professor of History, Valdosta State College, Valdosta, Ga._^<g_
Centers for Disease Control and Prevention, Atlanta, Ga._^<g_
Boston University, Boston, Mass., and Harvard University, Cambridge, Mass._^<g_
Lady Margaret Professor of Divinity, Oxford University, Oxford, England._^<g_
Professor of Health Sciences and Dean, School of Allied Health Professions, State University of New York, Stony Brook._^<g_
Department of Chemistry, Princeton University, Princeton, N.J._^<g_
Engineering Consultant and Writer._^<g_
Professor, California State University, Los Angeles._^<g_
Coadjutant Professor of Psychology, Livingston College, Rutgers University, New Brunswick, N.J._^<g_
Guest Scholar, Brookings Institution; Former Director, Internal Defense, United States Department of State._^<g_
Department of Asian and Middle Eastern Studies, University of Pennsylvania, Philadelphia._^<g_
School of the Art Institute of Chicago, Author of _^<i_The Munich Secession_^>i_._^<g_
Contributing Editor, _^<i_The Burns Mantle Theater Yearbook: Best Plays_^>i_._^<g_
Professor of Geological Science, University of Washington, Seattle._^<g_
Professor of Music, University of Michigan, Ann Arbor._^<g_
Assistant Professor, University of Wisconsin, Milwaukee._^<g_
Professor of Linguistics, Barnard College and Columbia University, New York City._^<g_
Associate Professor, University of Missouri, St. Louis._^<g_
Member of the Faculty, New School for Social Research, New York City._^<g_
Writer and Critic, Author of _^<i_The Engine of the Night: Science Fiction in the Eighties_^>i_._^<g_
Associate Dean, College of Arts and Sciences, University of Vermont, Burlington._^<g_
Professor, Division of Humanities and Social Sciences, California Institute of Technology, Pasadena._^<g_
Research and Editorial Director, The Lehrman Institute, New York City._^<g_
Professor of Medicine and Head, Infectious Diseases, University of Virginia School of Medicine, Charlottesville._^<g_
College of Business Administration, Marquette University, Milwaukee, Wis._^<g_
Assistant to the President, American Kennel Club, New York City._^<g_
Professor, Department of French and Italian, University of Massachusetts, Amherst._^<g_
Associate Professor of Anthropology, University of Pennsylvania, Philadelphia._^<g_
Professor of Philosophy, University of Vermont, Burlington._^<g_
Professor of History and African-American Studies, Northeastern University, Boston, Mass._^<g_
Professor of Sociology and Psychiatry, Michigan State University, East Lansing._^<g_
Professor of Forestry, Michigan State University, East Lansing._^<g_
Visiting Professor of Film, Boston University, Boston._^<g_
Adjunct Professor of Nutrition and Dietetics, Western Carolina University, Cullowhee, N.C._^<g_
Professor of Film and Television Criticism, Annenberg School of Communications, University of Southern California, Los Angeles._^<g_
Professor and Chair, Department of Anthropology, Rice University, Houston, Tex._^<g_
Consultant, AT_^<o!E221_T; Bell Laboratories; Business Planning, Product Requirements, and Customer Communications Groups in the Interactive Information Systems Department._^<g_
Professor and Chair, Department of Sociology, University of South Carolina, Columbia._^<g_
Lecturer in English, Vassar College, Poughkeepsie, N.Y._^<g_
Adjunct Professor of Physics, Nova University, Dania, Fla._^<g_
Associate Professor, Department of Theater and Dance, Texas Technical University, Lubbock, Tex._^<g_
Director, Jefferson Sports Medicine Center, Philadelphia, Pa._^<g_
Managing Editor, American College of Hospital Administrators, Chicago._^<g_
Editor, _^<i_Performing Arts Journal_^>i_._^<g_
Associate Professor, Department of Popular Culture, Bowling Green State University, Bowling Green, Ohio._^<g_
Music Critic, _^<i_Chicago Sun-Times_^>i_._^<g_
Professor of Music, University of Chicago, Chicago._^<g_
Professor of Food Science & Nutrition, University of Missouri, Columbia._^<g_
Assistant Professor, University of Texas, San Antonio._^<g_
Leo S. Bing Professor of Literature, University of Southern California, Los Angeles._^<g_
Associate Professor, Department of Landscape Architecture and Regional Planning, University of Massachusetts, Amherst._^<g_
Professor of Medicine, University of Pennsylvania School of Medicine, Philadelphia._^<g_
Director, Division of Natural Areas, Eastern Kentucky University, Richmond._^<g_
Professor of Visual Arts, University of East Anglia, Norwich, England._^<g_
Professor of Portuguese, New York University, New York City._^<g_
Professor of Political Science and Associate Director of the Institute of Latin American Studies, University of North Carolina, Chapel Hill._^<g_
F. M. Cone Distinguished Service Professor, University of Chicago Divinity School, Chicago._^<g_
Professor of Political Science, Pennsylvania State University, University Park._^<g_
Assistant Professor of Pathology, University of Tennessee Center for the Health Sciences, Memphis._^<g_
Professor of English, University of Chicago, Chicago._^<g_
Professor, University of Delaware, Newark._^<g_
Research Professor, University of Puerto Rico, Rio Piedras._^<g_
Associate Professor of Japanese, Stanford University, Stanford, Calif._^<g_
Professor of English, Queens College, City University of New York, Flushing._^<g_
Professor of Russian and Comparative Literature, University of Chicago, Chicago._^<g_
Professor of French, Syracuse University, Syracuse, N.Y._^<g_
Regent's Professor of Geology, Lamar University, Beaumont, Tex._^<g_
Professor of Art, North Texas State University, Denton._^<g_
Department of Ophthalmology, University of Florida, Gainesville._^<g_
Vice-President, Research and Development and Regulatory Affairs, Ovaltine Products, Inc., Villa Park, Ill._^<g_
Associate Professor of Neurology, University of Utah College of Medicine, Salt Lake City._^<g_
Professor and Chairperson, Department of Geography, University of Arkansas, Fayetteville._^<g_
Professor of English, California State University, Long Beach._^<g_
Sterling Professor Emeritus of French, Yale University, New Haven, Conn._^<g_
Department of History and Office for History of Science and Technology, University of California, Berkeley._^<g_
Professor of Economics, University of California at Davis, Davis._^<g_
Professor of Biology, Rider College, Lawrenceville, N.J._^<g_
Professor of Plant Science, University of Massachusetts, Amherst._^<g_
Assistant Professor of Physics, James Franck Institute, University of Chicago, Chicago._^<g_
Professor of Comparative Literature and Italian, State University of New York, Buffalo._^<g_
Retired Supervisory Chemist, Southern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture._^<g_
Department of Art History, University of Pennsylvania, Philadelphia._^<g_
Department of Political Science, McMaster University, Hamilton, Ontario, Canada._^<g_
Associate Professor of History, Southern Methodist University, Dallas, Tex._^<g_
Anthropologist, University of Wisconsin, Madison._^<g_
Professor of Psychology, University of Michigan, Ann Arbor._^<g_
Professor of Pharmacy, University of Montana, Missoula._^<g_
Associate Professor of Geography, University of Vermont, Burlington._^<g_
Information and Documentation Centre for the Geography of the Netherlands, Utrecht._^<g_
Professor of Dutch Languages and Literature, University of London, London._^<g_
Professor, American Studies and Art History Departments, University of Texas, Austin._^<g_
Consultant, Director, International Desalination Association._^<g_
Professor of Industrial Engineering, Department of Public Affairs and International Development, Columbia University, New York City._^<g_
Professor of English and History, George Mason University, Fairfax, Va._^<g_
American Geophysical Union, Lamont Doherty Geological Observatory of Columbia University, Palisades, N.Y._^<g_
Department of History, University of California, Berkeley, Calif._^<g_
Lecturer, Department of English and Comparative Literature, University of Warwick, Coventry, Warwickshire, England._^<g_
Professor of Journalism, Emeritus, University of Missouri, Columbia._^<g_
Professor of Horticulture and Dean of Instruction, Cook College, Rutgers University, New Brunswick, N.J._^<g_
Professor of Mathematics, University of Vermont, Burlington._^<g_
Curatorial Assistant, Museum of Modern Art, New York City._^<g_
Professor of History, University of Minnesota, Minneapolis._^<g_
Professor and Chairman, Department of Zoology, University of Toronto, Toronto._^<g_
Assistant Vice-President and Chief Scientist, Communications Satellite Corporation, Washington, D.C._^<g_
Professor of Church History and Patristics, St. Vladimir's Orthodox Theological Seminary, and Professor of History, Fordham University, New York City._^<g_
Associate Professor of History and Director, Council of International Studies, State University of New York, Buffalo._^<g_
Curator of Ferns, New York Botanical Garden, Bronx._^<g_
Professor of Economic Geography, University of Rome, Rome._^<g_
Professor, University of North Carolina, Chapel Hill._^<g_
Professor of History, Illinois Benedictine College, Lisle._^<g_
Associate Professor of German, University of Virginia, Charlottesville._^<g_
Professor of History, University of Houston, Houston, Tex._^<g_
Professor of Liturgies, Seabury-Western Theological Seminary, Evanston, Ill._^<g_
Recording and Product Design Engineer, Author of Articles on Audio and Video Technology._^<g_
Associate Curator, European Paintings, Metropolitan Museum of Art, New York City._^<g_
Professor of Physics, University of Maryland, College Park._^<g_
Professor, Queens College, City University of New York, Flushing._^<g_
Professor of Medical Psychology and Associate Professor of Pediatrics, The Johns Hopkins University School of Medicine and Hospital, Baltimore, Md._^<g_
Author and Former Music Critic, _^<i_Chicago Daily News_^>i_._^<g_
Former Chairman, Department of Anthropology, Rutgers University, New Brunswick, N.J._^<g_
Professor of History, Northwestern University, Evanston, Ill._^<g_
Professor of Statistics, Purdue University, West Lafayette, Ind._^<g_
Research Professor in English, Southern Illinois University, Carterville._^<g_
Professor of Horticulture, University of Arkansas, Fayetteville._^<g_
Professor of Philosophy, Phillips University, Enid, Okla._^<g_
Professor, Department of Education Administration, Michigan State University, East Lansing._^<g_
Professor of History, University of Southern California, Los Angeles._^<g_
Editor, _^<i_American Craft_^>i_._^<g_
Professor of Latin American Literature, University of California, Santa Cruz._^<g_
Assistant Professor of Psychology, Dartmouth College, Hanover, N.H._^<g_
Director, Royal Pavilion, Art Gallery and Museums, Brighton, East Sussex, England._^<g_
Professor of Biophysics and Biochemistry, Yale University, New Haven, Conn._^<g_
Associate Curator, American Museum of Natural History, New York City._^<g_
Professor Emeritus of Geography, University of Oklahoma, Norman._^<g_
Research and Development Manager, Weir Westgarth, Ltd., Glasgow, Scotland._^<g_
Former Research Geologist, U.S. Geological Survey, and Adjunct Professor, Department of Geosciences, University of Arizona, Tucson._^<g_
Executive Director, Social Science Education Consortium, Inc., Boulder, Colo._^<g_
Associate Professor of History, State University College, Fredonia, N.Y._^<g_
Associate Professor of Chemistry, Rutgers University, New Brunswick, N.J._^<g_
Erindale College, University of Toronto, Toronto, Ontario._^<g_
Associate Professor of English, Syracuse University, Syracuse, N.Y._^<g_
Manager, Information Department, Alcoa Technical Center, ALCOA, Alcoa Center, Pa._^<g_
Professor of Veterinary Medicine, Kansas State University, Manhattan._^<g_
Associate Professor of Geography, University of Houston, Houston, Tex._^<g_
Professor, Physical Science Department, Cypress College, Cypress, Calif._^<g_
Chairman and Professor, Department of Geography and Geology, Indiana State University, Terre Haute._^<g_
Supervisory Research Chemist, Oilseeds Crops Laboratory, Northern Regional Research Center, U.S. Department of Agriculture, Peoria, Ill._^<g_
Professor of Psychology, Carnegie-Mellon University, Pittsburgh, Pa._^<g_
Associate Professor of Theater Arts, University of California, Los Angeles._^<g_
Vilas Research Professor, University of Wisconsin, Madison._^<g_
Professor of Spanish, University of Missouri, Columbia._^<g_
Professor of Medicine, Medical College of Virginia, Richmond._^<g_
Professor of Geography and Chairman of the Geography and Geology Department, University of Wisconsin, Stevens Point._^<g_
Assistant Secretary of the Treasury, United States Department of the Treasury, Washington, D.C._^<g_
Professor of Political Science, University of West Florida, Pensacola._^<g_
Associate Professor of Linguistics, University of California, Los Angeles._^<g_
Professor Emeritus, New York State University College at New Paltz._^<g_
Professor of Social Work, San Francisco State University, San Francisco._^<g_
Professor of Geography, University of Michigan, Ann Arbor._^<g_
Assistant Professor of Geography, University of Oregon, Eugene._^<g_
Associate Professor of Anesthesiology, University of Pennsylvania, Philadelphia._^<g_
Professor of History and Government, U.S. Coast Guard Academy, New London, Conn._^<g_
Former Assistant Secretary of State for Near Eastern and South Asian Affairs; Senior Fellow, Council on Foreign Relations._^<g_
Professor of English, University of Missouri, St. Louis._^<g_
Professor of Geology, Indiana University, Bloomington._^<g_
Professor Emeritus, Department of Nuclear Engineering, North Carolina State University, Raleigh._^<g_
Owner and General Manager, Jay C. Musser Consulting Chemist, Mount Joy, Pa._^<g_
Professor of Business Administration, Rutgers University, New Brunswick, N.J._^<g_
Developmental Biologist, Yerkes Regional Primate Research Center, Emory University, Atlanta, Ga._^<g_
Professor, and Director, National Institute of Polar Research, Tokyo._^<g_
Professor and Chief, Youth Services, Department of Psychiatry, University of Michigan, Ann Arbor._^<g_
Professor of History, Western Michigan University, Kalamazoo._^<g_
Professor and Chairman, Department of Humanistic and Behavioral Studies, Boston University, Boston._^<g_
Associate Professor of History, Duke University, Durham, N.C._^<g_
Lecturer, Moorpark College, Moorpark, Calif._^<g_
Assistant Professor of History, Merrimack College, North Andover, Mass._^<g_
Professor of Machine Technology, Lane Community College, Eugene, Oreg._^<g_
Director, Louis A. Warren Lincoln Library and Museum, Fort Wayne, Ind._^<g_
Assistant Professor of Art History, University of Delaware, Newark._^<g_
Assistant Professor of Naval Architecture, United States Naval Academy, Annapolis, Md._^<g_
Arts Writer._^<g_
Professor of Psychology, Cornell University, Ithaca, N.Y._^<g_
Professor of Church History, United Theological Seminary, Dayton, Ohio._^<g_
Professor of Zoology, University of Alberta, Edmonton._^<g_
Professor of Art History, University of Minnesota, Minneapolis._^<g_
Professor Emeritus of Journalism, University of Oregon, Eugene._^<g_
Chairman, Department of Chemistry, David Lipscomb College, Nashville, Tenn._^<g_
Professor of Music and Anthropology, University of Illinois, Urbana._^<g_
Instructor, School of Art and Art History, University of Iowa, Iowa City._^<g_
Senior Research Scholar, Research Institute on International Change, and Director of Comparative Defense Studies Program, Columbia University, New York City._^<g_
Professor of Animal Science, Emeritus, University of Illinois, Urbana._^<g_
Research Scientist, Polymer Science Institute, University of Massachusetts, Amherst._^<g_
Professor of Religious Studies, The Ungerleider Distinguished Scholar of Judaic Studies, Brown University, Providence, R.I._^<g_
Reader in Zoology, University of Bristol, Bristol, England._^<g_
Principal and Vice-Chancellor, University of Dundee, Dundee, Scotland._^<g_
Member of the Technical Staff, Jet Propulsion Laboratory, California Institute of Technology, Pasadena._^<g_
Professor of History and Asian Studies, University of Northern Iowa, Cedar Falls._^<g_
Professor of Music, Virginia Commonwealth University, Richmond._^<g_
Critic, _^<i_Dancemagazine_^>i_ and _^<i_Classical Music Weekly_^>i_._^<g_
Assistant Professor, Ohio Wesleyan University, Delaware._^<g_
Professor of Biology, La Salle College, Philadelphia._^<g_
Professor Emeritus, Tufts University, Medford, Mass._^<g_
Professor of Geography, University of Western Ontario, London._^<g_
Professor of Physical Chemistry, University of California, Los Angeles._^<g_
Professor of Botany, Connecticut College, New London._^<g_
Professor of History, Southern Methodist University, Dallas, Tex._^<g_
Carnegie Corporation of New York, Washington, D.C._^<g_
Professor, University of Paris, Paris._^<g_
Attorney, Speiser & Krause, P.C., New York City._^<g_
Dean and Professor of Communications, Annenberg School of Communications, University of Southern California, Los Angeles._^<g_
Former Professor of Education Policy, Planning, and Administration, College of Education, University of Maryland, College Park._^<g_
Associate Professor of History, Wheaton College, Wheaton, Ill._^<g_
Department of Zoology, University of Goteborg, Goteborg, Sweden._^<g_
Associate Professor, Energy and Resources Group, University of California, Berkeley._^<g_
Department of International Relations, Boston University, Boston, Mass._^<g_
Senior Vice-President, Sotheby Parke Bernet, Inc., New York City._^<g_
Professor of History of Christianity, Garrett-Evangelical Theological Seminary, Evanston, Ill._^<g_
Research Associate, Vector Biology Laboratory, University of Notre Dame, Notre Dame, Ind._^<g_
University Professor, Brown University, Providence, R.I._^<g_
Professor Emeritus of Engineering Sciences, Arizona State University, Tempe._^<g_
Professor of Biological Sciences, Moss Landing Marine Laboratories, Moss Landing, Calif._^<g_
Associate Professor of Chemistry, University of New Haven, West Haven, Conn._^<g_
President, Williams College, Williamstown, Mass._^<g_
Author of _^<i_Spacefarers of the Eighties and Nineties_^>i_, and, with James E. Oberg, of _^<i_Pioneering Space_^>i_._^<g_
Space engineer, Author of _^<i_Red Star in Orbit_^>i_ and _^<i_Mission to Mars_^>i_._^<g_
Chief Chemist, Benjamin Moore & Co., Newark, N.J._^<g_
Professor of Pathology and Head, Section of Clinical Pathology, University of Michigan Medical School, Ann Arbor._^<g_
Associate Professor of Political Science, Nebraska Wesleyan University, Lincoln._^<g_
Professor of History, Fordham University, New York City._^<g_
Associate Professor of Egyptology, Associate Curator, Egyptian Section, The University Museum, University of Pennsylvania, Philadelphia._^<g_
Associate Professor, Virginia Polytechnic Institute and State University, Blacksburg._^<g_
Publisher and Editor, _^<i_Jack O'Dwyer's Newsletter_^>i_._^<g_
Professor of Psychiatry, University of Chicago, Chicago._^<g_
Chairman, Department of Psychiatry, Michael Reese Hospital and Medical Center, Chicago._^<g_
Professor of Sociology, University of California, Berkeley._^<g_
Department of English, Temple University, Philadelphia._^<g_
Associate Professor, University of Victoria, Victoria, British Columbia._^<g_
The Wire Association International, Inc., Guilford, Conn._^<g_
Vice-President for Academic Affairs and Professor of History, New York University, New York City._^<g_
Professor of Silviculture, College of Forest Resources, University of Washington, Seattle._^<g_
Former Editor, _^<i_Electro-Technology Magazine_^>i_._^<g_
President, FeedAForm, Inc., Westwood, Mass._^<g_
Professor, Department of Politics, New York University, New York City._^<g_
Head, Division of Pharmaceutics, University of North Carolina, Chapel Hill._^<g_
Assistant Director, College and Community Relations, Fashion Institute of Technology, New York City._^<g_
Professor, Weston School of Theology, Cambridge, Mass._^<g_
Professor of Computer Science, University of Utah, Salt Lake City._^<g_
Professor of Ancient Near Eastern History and Literature, University of Michigan, Ann Arbor._^<g_
Professor of Psychiatry, Yale University, New Haven, Conn._^<g_
Associate Professor, Department of Politics, Catholic University of America, Washington, D.C._^<g_
Senior Scientist, California Academy of Sciences, San Francisco._^<g_
Department of History, Michigan State University, East Lansing._^<g_
Professor and Head, Department of Mathematics, North Carolina State University, Raleigh._^<g_
Professor of Psychology, Claremont Graduate School, Claremont, Calif._^<g_
Director and Professor of Astronomy, Lick Observatory, University of California, Santa Cruz._^<g_
Lecturer in Arabic, School of Oriental and African Studies, University of London, London._^<g_
Professor of Geology, Yale University, New Haven, Conn._^<g_
Associate Professor, Department of Pomology and Viticulture, New York State Experiment Station, Geneva._^<g_
Professor of Anthropology, Queens College, City University of New York, Flushing._^<g_
Assistant Professor of Electrical Engineering, Stanford University, Stanford, Calif._^<g_
Assistant Professor of Chemistry, University of Chicago, Chicago._^<g_
Professor of Education, Virginia Commonwealth University, Richmond._^<g_
Professor of Romance Languages and Comparative Literature, Queens College and Graduate Center, City University of New York, Flushing._^<g_
Assistant Professor, Department of Physics, Pennsylvania State University, University Park._^<g_
Professor of Educational Psychology and Research, Duke University, Durham, N.C._^<g_
Research Astrophysicist, NASA Johnson Space Center, Houston, Tex._^<g_
Assistant Professor, Gynecology and Obstetrics, Johns Hopkins University Medical School, Baltimore, Md._^<g_
Professor of Chinese, University of Oregon, Eugene._^<g_
Professor, School of Printing Curator, Melbert B. Cary, Jr., Graphic Arts Collection, Rochester Institute of Technology, Rochester, N.Y._^<g_
Professor of History, Western Illinois University, Macomb._^<g_
Associate Professor of History, Kent State University, Kent, Ohio._^<g_
Assistant Professor of History of Science and Chemistry, Eisenhower College, Seneca Falls, N.Y._^<g_
Professor of Anthropology, Memorial University of Newfoundland, Saint John's._^<g_
Senior Management Consultant, SRI International, Menlo Park, Calif._^<g_
Distinguished Visiting Professor of Education, Western Carolina University, Cullowhee, N.C._^<g_
Professor of Music, University of Miami, Coral Gables, Fla._^<g_
Publisher, _^<i_Sandy Parker Reports_^>i_, and Associate Editor, _^<i_Fur Chic_^>i_ Magazine._^<g_
Historian, History and Museums Divisions Headquarters, U.S. Marine Corps, Washington, D.C._^<g_
Professor of Philosophy, Columbia University, New York City._^<g_
Lecturer, History of Art, Freshman Honors Program, University of Delaware, Newark._^<g_
Professor, Institute of Oceanography, University of British Columbia, Vancouver._^<g_
Professor of Political Science, University of California, Berkeley._^<g_
Professor of Anthropology, Columbia University, New York City._^<g_
Professor of Oncology and Pathology, McArdle Laboratory for Cancer Research, University of Wisconsin, Madison._^<g_
Department of Psychology, Washington University, St. Louis, Mo._^<g_
Professor of Biomedical Engineering, Duke University, Durham, N.C._^<g_
Senior Policy Analyst, New Jersey Employment and Training Commission._^<g_
Lecturer, Hunter College, New York City._^<g_
Art Historian._^<g_
Professor of Psychiatry, Albert Einstein College of Medicine, Bronx, N.Y._^<g_
Moscow Institute of Physics and Technology, Moscow, Russia._^<g_
Professor of International Food Economics, Cornell University, Ithaca, N.Y._^<g_
Professor of American History, Cornell University, Ithaca, N.Y._^<g_
New York Hospital, Cornell Medical Center, Westchester Division, New York._^<g_
President, Museum Marketing Associates, Inc., New York City._^<g_
Former Assistant for Photography, Department of Prints, Drawings and Photographs, Philadelphia Museum of Art, Philadelphia._^<g_
Former Conservator, Department of Paintings and Sculpture, Art Institute of Chicago, Chicago._^<g_
Director, Bartol Research Foundation of The Franklin Institute, University of Delaware, Newark._^<g_
Chairman and Professor, Department of Political Science, Rutgers University, New Brunswick, N.J._^<g_
Editor and Translator of _^<i_Kalevala Mythology_^>i_._^<g_
United Lodge of Theosophists, New York City._^<g_
Professor of Philosophy, Washington University, Saint Louis, Mo._^<g_
Author._^<g_
Professor of Fine Arts, New York University, New York City._^<g_
Project Manager, Environmental Assessment Council, Inc., New Brunswick, N.J._^<g_
Professor of Philosophy, University of Washington, Seattle._^<g_
Professor of Political Science, Northern Arizona State University, Flagstaff._^<g_
Professor of Geography and History, Indiana University, Bloomington._^<g_
Russian Research Center, Harvard University, Cambridge, Mass._^<g_
Director, Chestnut Mountain Research Center, Taylors, S.C. Author of _^<i_The Complete Guide to Home Appliances_^>i_._^<g_
Professor of History, Syracuse University, Syracuse, N.Y._^<g_
Director of Technology, Battery Products Division, Union Carbide Corporation, Cleveland, Ohio._^<g_
Professor of Advertising, University of Wisconsin, Madison._^<g_
Director, Language Department, University of South Florida, Tampa._^<g_
Editor, _^<i_Jane's Weapon Systems_^>i_._^<g_
Professor of Neuroscience, Stanford University, Stanford, Calif._^<g_
Editorial Director, _^<i_The Whole Horse Catalog_^>i_, New York City._^<g_
Assistant Professor of English, Virginia Commonwealth University, Richmond._^<g_
Editorial Board, _^<i_Hudson Review_^>i_, and Professor of English, Amherst College, Amherst, Mass._^<g_
Member of the Faculty, Rockford School of Medicine, University of Illinois Ophthalmology Section, Rockford, and Consultant in Ophthalmology, U.S. Army Health Services Command._^<g_
Professor of Civil and Environmental Engineering, Polytechnic Institute of New York, Brooklyn._^<g_
Associate Professor of History of Canadian Education, University of Western Ontario, London._^<g_
Professor of History, University of California, Santa Barbara._^<g_
Instructor, California State University, Northridge._^<g_
Professeur Agrege, Institut d'histoire et de sociopolitique des sciences, Universite de Montreal, Montreal._^<g_
Author of _^<i_Byron: The Years of Fame_^>i_, _^<i_Byron in Italy_^>i_, _^<i_Alexander Pope: The Education of Genius_^>i_, and other works._^<g_
Assistant Professor of Music, Case Western Reserve University, Cleveland, Ohio._^<g_
Assistant Professor of Geography, Eastern Kentucky University, Richmond._^<g_
Institute of Government and Public Affairs, University of Illinois, Chicago._^<g_
Research Scientist, Exxon Corporation, Linden, N.J._^<g_
Professor and Director of Livingston College Theater Arts Department, Rutgers University, New Brunswick, N.J._^<g_
Professor of Psychology, State University of New York, Stony Brook._^<g_
Associate Professor of Linguistics, The University of Calgary, Calgary, Alberta._^<g_
Research Associate, Huron Institute, Cambridge, Mass._^<g_
Professor of the History of Technology, Emeritus, Harvey Mudd College, Claremont, Calif._^<g_
Bakhmeteff Professor Emeritus of Russian Studies, Columbia University, New York City._^<g_
Research Analyst, National Commission for Economic Conversion and Disarmament._^<g_
Department of Rehabilitation Medicine, Mount Sinai Medical Center, New York City._^<g_
Associate Professor of Biological Sciences, University of Pittsburgh, Pittsburgh, Pa._^<g_
Associate Professor of Biological Sciences, Northern Kentucky University, Highland Heights._^<g_
Associate Professor of International Studies, University of Washington, Seattle._^<g_
Professor of Chemistry, East Michigan University, Ypsilanti._^<g_
Assistant Professor of Metallurgical Engineering, University of Missouri, Rolla._^<g_
Chairman, Department of 20th Century Painting & Sculpture, Smithsonian Institution, Washington, D.C._^<g_
Assistant Professor, Environmental and Urban Systems, Virginia Polytechnic Institute and State University, Blacksburg._^<g_
Associate Professor of Theology, St. Louis University, St. Louis, Mo._^<g_
Former Professor of Theology and Ecumenics, Hartford Seminary Foundation, Hartford, Conn._^<g_
Former Arthur S. Localio Professor of Surgery, New York University, New York City._^<g_
Contributing Editor, _^<i_Art in America_^>i_, and Instructor, School of Visual Arts, New York City._^<g_
Charles Bullard Professor of Forestry, Emeritus, Harvard University, Cambridge._^<g_
Research Leader, Physics and Engineering, U.S. Salinity Laboratory, Riverside, Calif._^<g_
Curator, Gulbenkian Museum of Oriental Art, University of Durham, England._^<g_
Professor of Geography, Carlton University, Ottawa, Ontario._^<g_
Associate Curator, Department of Botany, Smithsonian Institution, Washington, D.C._^<g_
Major, U.S. Army (ret.), Biologist and Virologist, Laboratory of Toxicology, National Cancer Institute, National Institute of Health, Bethesda, Md._^<g_
Professor of Music, University of California, Los Angeles._^<g_
Assistant Professor of Journalism, California State University, Los Angeles._^<g_
Associate Director (Education), Comprehensive Cancer Center of Metropolitan Detroit, and Associate Professor of Oncology, Wayne State University School of Medicine, Detroit._^<g_
Indiana University, Bloomington._^<g_
Associate Professor of Mining Engineering, Colorado School of Mines, Golden._^<g_
Professor of English, University of Pennsylvania, Philadelphia._^<g_
Associate Professor of Geography, University of Tennessee, Knoxville._^<g_
Professor of Psychology, University of Houston, Houston, Tex._^<g_
Professor of Political Science, George Washington University, Washington, D.C._^<g_
Associate Professor of the Classics, Florida State University, Tallahassee._^<g_
Writer._^<g_
Assistant Professor of Medicine, University of Virginia School of Medicine, Charlottesville._^<g_
Research Fellow in Biology, Princeton University, Princeton, N.J._^<g_
Professor of Pharmacology Emeritus, Massachusetts College of Pharmacy and Allied Health Sciences, Boston._^<g_
Associate Professor of Mechanical Engineering, Virginia Polytechnic Institute and State University, Blacksburg._^<g_
Associate Professor of Zoology, University of Florida, Gainesville._^<g_
Professor of Law, Yale Law School, New Haven, Conn._^<g_
Assistant Professor of Modern Languages, Phillips Exeter Academy, Exeter, N.H._^<g_
Professor of Political Science, Miami University, Oxford, Ohio._^<g_
Professor of Science Education, University of Oklahoma, Norman._^<g_
Associate Professor of Prosthodontics, State University of New York, School of Dental Medicine, Stony Brook._^<g_
Research Staff Associate, Lamont-Doherty Geological Observatory, Columbia University, New York City._^<g_
Consultant on Physical Problems._^<g_
Assistant Curator, Yale University Collection of Musical Instruments, New Haven, Conn._^<g_
Director, Yale Collection of Musical Instruments and Associate Professor of Organology, Yale University, New Haven, Conn._^<g_
Associate Professor of Biology, State University College, Buffalo, N.Y._^<g_
Professor of Horticulture, University of California, Riverside._^<g_
Associate Professor, Department of Political Science, Rutgers University, New Brunswick, N.J._^<g_
Instructor in Psychology, University of Tennessee, Knoxville._^<g_
Dance Critic and Writer._^<g_
Japan Project, University of Tennessee at Chattanooga._^<g_
Glynn Research Institute, Bodmin, Cornwall, England._^<g_
Professor of Politics, University of Southampton, Southampton, England._^<g_
Research Assistant, Woods Hole Oceanographic Institution, Woods Hole, Mass._^<g_
Professor of English, Rutgers University, New Brunswick, N.J._^<g_
Professor of Geography, Central Connecticut State College, New Britain._^<g_
Professor of Psychology, University of Cincinnati, Cincinnati, Ohio._^<g_
Professor Emeritus, Colorado State University, Boulder._^<g_
Associate Professor of Biology and Zoology, University of Manitoba, Winnipeg._^<g_
Assistant Professor of Art History, San Diego State University, San Diego, Calif._^<g_
Wilson Professor of Political Science, University of Rochester, Rochester, N.Y._^<g_
Professor of Political Science, University of Wisconsin, Madison._^<g_
Professor of Economics, Temple University, Philadelphia._^<g_
Director, Autism Research Institute, San Diego, Calif._^<g_
Adjunct Professor of Mechanical Engineering, University of Colorado, Boulder._^<g_
Boyd Professor of Psychology, Louisiana State University, Baton Rouge._^<g_
Professor of the History of Medicine, University of Wisconsin, Madison._^<g_
Professor of Germanic Studies, University of Sheffield, Sheffield, England._^<g_
Dept. of Asian Civilizations, Australian National University, Canberra._^<g_
Mayo Clinic and Mayo Medical School, Rochester, Minn._^<g_
Assistant Professor of Chemistry, Rutgers, The State University of New Jersey, New Brunswick._^<g_
Associate Professor of Near Eastern Studies, University of Toronto, Toronto, Ontario._^<g_
Assistant Professor of History, University of Wyoming, Laramie._^<g_
Professor, History of Art, Newcomb College, Tulane University, New Orleans, La._^<g_
Recording Engineer, CBS/Columbia Records, New York City._^<g_
Curator of the Herbarium, Illinois Natural History Survey, Urbana._^<g_
Library Assistant, Latin American Library, Tulane University, New Orleans, La._^<g_
Associate Critic, _^<i_Dancemagazine_^>i_._^<g_
Associate Professor of Art, Williams College, Williamstown, Mass._^<g_
Professor of English, University of Cincinnati, Cincinnati, Ohio._^<g_
Professor of Geography, University of British Columbia, Vancouver._^<g_
Dean, School of Business, Shippensburg State College, Shippensburg, Pa._^<g_
Geographer, former U.S. Army Engineer, Topographic Laboratories, Fort Belvoir, Va._^<g_
Professor of Zoology, California State Polytechnic University, Pomona._^<g_
Associate Professor in Art History, University of New Mexico, Albuquerque._^<g_
Head, Theory Composition, University of Texas, Austin._^<g_
Assistant Chief Historian, History and Museums Division, Headquarters, U.S. Marine Corps, Washington, D.C._^<g_
Drug Information Specialist, Emory University Hospital, Atlanta, Ga._^<g_
President, Telegen, Palo Alto, Calif._^<g_
Professor of Geography, University of Maine, Farmington._^<g_
Associate Professor of Biology, Bowling Green State University, Bowling Green, Ohio._^<g_
Professor of Geology, Emeritus, St. Lawrence University, Canton, N.Y._^<g_
Professor of Zoology, Ohio University, Athens._^<g_
Institute of Marine and Coastal Sciences, Rutgers University, New Brunswick, N.J._^<g_
Professor of Chemistry, Dickinson College, Carlisle, Pa._^<g_
Associate Professor of Government, New Mexico State University, Las Cruces._^<g_
Professor of History, Duke University, Durham, N.C._^<g_
President, Alfred University, Alfred, N.Y._^<g_
Sophia Smith Professor of Sociology and Anthropology, Smith College, Northampton, Mass._^<g_
Professor of History, Rutgers University, Newark, N.J._^<g_
Research Scientist, New York State Drug Abuse Commission, New York City._^<g_
Professor of English, Columbia University, New York City._^<g_
Primary Examiner (Retired), U.S. Patent _^<o!E221_ Trademark office, Washington, D.C._^<g_
Professor of History, University of Michigan, Ann Arbor._^<g_
Professor of English, Indiana University, Bloomington._^<g_
Curator of Collections, Memorial Art Gallery, University of Rochester, Rochester, N.Y._^<g_
Professor of Sociology, Queens College, City University of New York, Flushing._^<g_
Professor, Department of Art History and Archaeology, Columbia University, New York City._^<g_
Professor of Philosophy, Loyola University, New Orleans, La._^<g_
Dance Critic, _^<i_Wall Street Journal_^>i_._^<g_
Professor, History of Modern Art, University of Massachusetts, Amherst._^<g_
Professor of Geology, Western Washington University, Bellingham._^<g_
Professor of Entomology, University of Georgia, Athens._^<g_
Trade Advertising and Public Relations Manager, Oneida Ltd. Silversmiths, Oneida, N.Y._^<g_
Professor of East Asian Language and Cultures, City University of New York, New York City._^<g_
Professor of Psychology, Macalester College, St. Paul, Minn._^<g_
Academic Vice President for Arts, Sciences and Technology, Tufts University, Medford, Mass._^<g_
Museum of Fine Arts, Boston._^<g_
Associate Professor of Art History, University of Oregon, Eugene._^<g_
Department of Political Science, University of Connecticut, Storrs._^<g_
Professor of History, Rutgers University, New Brunswick, N.J._^<g_
Fellow of the British Academy._^<g_
Professor of Physics, Arizona State University, Tempe._^<g_
Professor of Ophthalmology, University of Florida College of Medicine, Gainesville._^<g_
Senior Research Anthropologist, Philadelphia Geriatric Center, Philadelphia._^<g_
Professor of Philosophy, Skidmore College, Saratoga Springs, N.Y._^<g_
Professor of Human Genetics, University of Michigan Medical School, Ann Arbor._^<g_
Assistant Director, Statistical Office, United Nations, New York City._^<g_
Professor of Economics, Emeritus, Yale University, New Haven, Conn._^<g_
Professor of Geography, University of Connecticut, Storrs._^<g_
Department of Clinical Pharmacology, Hoffmann-La Roche, Inc., Nutley, N.J._^<g_
Technical Writer, Kawasaki Motors Corp., Santa Ana, Calif._^<g_
Professor of English, University of Illinois, Chicago._^<g_
Professor of Political Science, University of North Carolina, Chapel Hill._^<g_
Professor of Drama, Stanford University, Stanford, Calif._^<g_
Director, Laboratory of Neurological Research, University of Southern California Medical Center, Los Angeles._^<g_
Environmental Education Consultant and Author._^<g_
Former Professor of Electrical Engineering, Michigan State University, East Lansing._^<g_
Professor of Physics and Astronomy, State University of New York, Buffalo._^<g_
Chief Forensic Chemist, New Jersey State Police, Forensic Science Bureau, West Trenton._^<g_
Professor of Sociology, University of California, Santa Barbara._^<g_
Professor of Sociology, City College, City University of New York, New York City._^<g_
Author of _^<i_The Radical Theatre Notebook_^>i_._^<g_
Associate Professor of Geography, Southern Connecticut State College, New Haven._^<g_
Associate Professor of Biblical Studies, Boston College, Chestnut Hill, Mass._^<g_
Professor of English, University of Washington, Seattle._^<g_
Professor of English, State University College, Fredonia, N.Y._^<g_
Professor of Plant Physiology, Utah State University, Logan._^<g_
Professor of Geography, University of Oklahoma, Norman._^<g_
Goodhart Professor of History, Bryn Mawr College, Bryn Mawr, Pa._^<g_
Professor of German, University of Edinburgh, Edinburgh, Scotland._^<g_
Professor, Emeritus, Department of Nutrition and Food Sciences, Utah State University, Logan._^<g_
Assistant Professor of Crop Breeding, Department of Agronomy, University of Maryland, College Park._^<g_
Professor of Geography, Ferris State College, Big Rapids, Mich._^<g_
Professor of Linguistics, University of Washington, Seattle._^<g_
Professor of Astronomy, University of Virginia, Charlottesville._^<g_
Assistant Professor of Architecture, Syracuse University, Syracuse, N.Y._^<g_
Editor, The Shoe String Press, Inc., Hamden, Conn._^<g_
Major, U.S. Army, Department of History, United States Military Academy, West Point, N.Y._^<g_
Professor of Germanic Languages, University of Nebraska, Lincoln._^<g_
The Rand Corporation, Santa Monica, Calif._^<g_
Professor of History, Illinois State University, Normal._^<g_
Department of Anthropology, Columbia University, New York City._^<g_
Curator, Division of Community Life, Smithsonian Institution, Washington, D.C._^<g_
Professor of Psychology, Wesleyan University, Middletown, Conn._^<g_
Assistant Professor of Political Science, Douglass College, Rutgers University, New Brunswick, N.J._^<g_
Professor of Mechanical Engineering, University of Rhode Island, Kingston._^<g_
Formerly, Professor of Finance, Hofstra University; Economist, Federal Reserve Bank of New York, New York City._^<g_
Associate Professor of Hebrew and Judaic Studies, New York University, New York City._^<g_
Associate Professor of Composition, Eastman School of Music, Rochester, N.Y._^<g_
Professor of History, College of New Rochelle, New Rochelle, N.Y._^<g_
Associate Professor of Mathematics, John Jay College of Criminal Justice, City University of New York, New York City._^<g_
Professor of History, St. Joseph's College, Philadelphia._^<g_
Director of Public Relations, American Association of Fund-Raising Counsel, New York City._^<g_
Professor, Department of Community/Family Medicine, University of California Medical School, San Diego._^<g_
Associate Professor of Zoology, Curator of Birds, University of Oklahoma, Norman._^<g_
Professor of Geology, Columbia University, New York City._^<g_
Geologist (ret.), U.S. Geological Survey, Ohio State University, Columbus._^<g_
Professor of Hebrew and Semitic Studies, University of Wisconsin, Madison._^<g_
Professor of Geology, Queens College, City University of New York, Flushing; Lamont Doherty Geological Observatory, Palisades, N.Y._^<g_
Writer for School of the Art Institute of Chicago._^<g_
Columnist, United Media Services, New York City._^<g_
Professor of Psychology, Brown University, Providence, R.I._^<g_
Department of Geography, University of Missouri, Columbia._^<g_
Staff Member (ret.), Los Alamos Scientific Laboratory, University of California, Los Alamos, N.Mex._^<g_
Certified Prosthetist Orthotist and Assistant Clinical Professor and Director of Prosthetics and Orthotics, Duke University, Durham, N.C._^<g_
Professor of Microbiology, Mount Sinai School of Medicine, New York City._^<g_
Paul C. Mangelsdorf Professor of Natural Science and Director, Botanical Museum, Harvard University, Cambridge, Mass._^<g_
Professor of English, University of Southern California, Los Angeles._^<g_
Professor of Anthropology, Southern Illinois University, Edwardsville._^<g_
University Assistant Lecturer in History of Science, University of Cambridge, and Director of Studies in History and Philosophy of Science, St. John's College, Cambridge, England._^<g_
Associate Professor of Political Science, State University of New York, Purchase._^<g_
Edwin D. Webb Professor of Law, New York University School of Law, New York City._^<g_
Professor of Foreign Languages, University of Miami, Coral Gables, Fla._^<g_
Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, Conn._^<g_
Art Historian._^<g_
Dean of the Graduate School and Professor of English, Georgetown University, Washington, D.C._^<g_
President, Environmental Media Consultants, Inc._^<g_
Chief Taxidermist, American Museum of Natural History, New York City._^<g_
Author of _^<i_Rugs and Wallhangings_^>i_._^<g_
Planning Consultant, National Gallery of Art, Washington, D.C._^<g_
Professor of Geography and Director, Center for Pacific Northwest Studies, Western Washington University, Bellingham._^<g_
Department of Art, University of Florida, Gainesville._^<g_
Professor of Education, University of Leeds, Leeds, England._^<g_
U.S. Navy (ret.) and Visiting Professor, Massachusetts Institute of Technology, Cambridge._^<g_
Author of _^<i_George B. McClellan: The Young Napoleon_^>i_._^<g_
Associate Professor of Psychology, Providence College, Providence, R.I._^<g_
National Science Foundation, Retired._^<g_
Professor of Classics, Brown University, Providence, R.I._^<g_
Professor of Slavic Literatures, Columbia University, New York City._^<g_
Professor of Pharmacology and Physiology, University of Chicago, Chicago._^<g_
Assistant Professor of Political Science, University of Arizona, Tucson._^<g_
Department of Obstetrics and Gynecology, Cleveland Metropolitan Hospital, Cleveland, Ohio._^<g_
Associate Professor of Drama, Tufts University, Medford, Mass._^<g_
President, Sentman Publishing Enterprises, Lake Forest, Ill._^<g_
Professor, Department of Management, Baruch College, City University of New York._^<g_
Mechanical Engineering Department, The Pennsylvania State University, College Park._^<g_
Technical Information Manager, Amstar Corporation, New York, N.Y._^<g_
Formerly Visiting Professor of English, University of Wisconsin, Madison._^<g_
Editor, _^<i_Soviet Geography Magazine_^>i_, New York City._^<g_
School of Education, Stanford University, Stanford, Calif._^<g_
Professor of English, University of Virginia, Charlottesville._^<g_
Senior Mathematician, Rand Corporation._^<g_
Council on International Educational Exchange._^<g_
Lecturer, Department of Psychiatry, Cambridge Hospital, Harvard Medical School, Cambridge, Mass._^<g_
Professor of Early Childhood Education, University of Illinois, Urbana-Champaign, Urbana._^<g_
Associate Professor of Anthropology, University of Pennsylvania, Philadelphia._^<g_
Senior Member, The Institute of Electrical and Electronic Engineers, and Associate of the London College of Music, Paddington College, London._^<g_
National Consultant in Education, American Foundation for the Blind, New York City._^<g_
Professor of Public Affairs, University of Texas, Austin._^<g_
Correspondent, _^<i_Time_^>i_ Magazine._^<g_
Research Scientist, U.S. Environmental Protection Agency._^<g_
Professor of Animal Sciences, Purdue University, West Lafayette, Ind._^<g_
Professor of English, Emeritus, University of Connecticut, Storrs._^<g_
School of African and Asian Studies, University of Sussex, Sussex, England._^<g_
Editor, _^<i_Tuesday_^>i_ Magazine._^<g_
Emeritus Professor of Canadian Studies, Mount Allison University, Sackville, New Brunswick._^<g_
Professor of Anesthesiology, Surgery, University of Utah Medical Center, Salt Lake City._^<g_
Assistant Professor of Art History, University of Victoria, Victoria, British Columbia._^<g_
Department of Agricultural Economics, Cornell University, Ithaca, N.Y._^<g_
Professor of Speech, Language, and Hearing, Temple University, Philadelphia._^<g_
Director, Center for Operations, Graduate School of Business, Columbia University, New York City._^<g_
Professor, Optical Science Center, University of Arizona, Tucson._^<g_
Professor of Law, Georgetown University, Washington, D.C._^<g_
Professor Emeritus, University of Massachusetts, Boston._^<g_
Deputy University Librarian, Australian National University, Canberra._^<g_
Instructor in Psychology, University of Tennessee, Knoxville._^<g_
President Emeritus, New York Botanical Garden, Bronx._^<g_
U.S. Forest Service, Research Triangle Park, N.C._^<g_
Chairman, Department of Radiology, North Shore University Hospital_^<o!E0_Cornell University Medical College, Manhasset, N.Y._^<g_
Editor, _^<i_The Week in Germany_^>i_, German Information Center, New York City._^<g_
Museum Specialist, National Museum of History and Technology, Smithsonian Institution, Washington, D.C._^<g_
Professor of Economics and Public Policy, University of Michigan, Ann Arbor._^<g_
President & Artistic Director, Accademia Monteverdiana Inc., Santa Barbara, Calif._^<g_
Chief, Branch of Experimental Geochemistry and Mineralogy, U.S. Geological Survey._^<g_
Professor of History, Macalester College, Saint Paul, Minn._^<g_
Professor of Anthropology, Arizona State University, Tempe._^<g_
Chairperson, Department of Sociology, George Washington University, Washington, D.C._^<g_
School of African and Asian Studies, University of Sussex, Sussex, England._^<g_
Professor of English, University of Toledo, Toledo, Ohio._^<g_
Professor of Linguistics, University of California, Los Angeles._^<g_
Professor of Sociology and Anthropology, University of Texas, El Paso._^<g_
Executive Director, Lamba Legal Defense and Education Fund, Inc., New York City; Adjunct Associate Professor of Law, New York University._^<g_
Professor of Political Science, Hunter College, City University of New York, New York City._^<g_
Deputy Project Specialist, Magellan, Jet Propulsion Laboratory, California Institute of Technology, Pasadena._^<g_
Associate Professor of Psychology, Yeshiva University, New York City._^<g_
Director, Winterthur Museum, Art Conservation Program, University of Delaware, Newark._^<g_
Professor Emeritus of Horticulture, University of California, Riverside._^<g_
Consultant, Author of _^<i_An Ocean Navigation Exercise_^>i_._^<g_
Emeritus Professor of History, Purdue University, Lafayette, Ind._^<g_
Former Scientific Director, U.S. Naval Observatory, Washington, D.C._^<g_
Professor of Communications, Fordham University, Bronx, N.Y._^<g_
Professor of Chemistry, University of California, Berkeley._^<g_
Sportswriter, _^<i_New York Times_^>i_._^<g_
Professor of German, University of Utah, Salt Lake City._^<g_
Professor of Aeronautics and Astronautics, University of Washington, Seattle._^<g_
Medical Director and Orthopedic Surgeon, Therasport, Tustin, Calif._^<g_
Lecturer in History of Religions, University of Chicago, Chicago._^<g_
Professor of Economics, Montana State University, Bozeman._^<g_
Professor of History, Northwestern University, Evanston, Ill._^<g_
Lecturer in History and Sociology of Science, University of Pennsylvania, Philadelphia._^<g_
Department of Botany, University of Maryland, College Park._^<g_
Assistant to the Chairman, Boston Architectural Center, Boston._^<g_
Assistant Professor of Psychiatry, Yale University, New Haven, Conn._^<g_
Instructor of Art History, New York University, New York City._^<g_
Professor of English, University of Rochester, Rochester, N.Y._^<g_
Professor, Memorial University of Newfoundland, St. John's._^<g_
Assistant Professor of English, The Johns Hopkins University, Baltimore, Md._^<g_
Alex Manoogian Professor of Modern Armenian History, University of Michigan, Ann Arbor._^<g_
Professor of Anatomical Sciences, School of Medicine, State University of New York, Stony Brook._^<g_
Professor of Engineering, University of California, Berkeley._^<g_
Associate Professor of English, Northeastern University, Boston._^<g_
Deputy Program Leader, University of California, Livermore._^<g_
Authors of _^<i_Forests of the World_^>i_ and _^<i_Wild Shores_^>i_._^<g_
Professor of Education and of Folklore, University of Pennsylvania, Graduate School of Education, Philadelphia._^<g_
Senior Scientist, Kodak Research Labs, San Diego, Calif._^<g_
Professor of Physics, State University of New York, Stony Brook._^<g_
Author of _^<i_Familiar Strangers: Gypsy Life in America_^>i_._^<g_
Professor of History, Monmouth College, West Long Branch, N.J._^<g_
Associate Curator of Fishes, Natural History Museum of Los Angeles County, Los Angeles._^<g_
Professor of Astronomy, University of Arizona, Tucson._^<g_
Dean of Humanities, California State College, San Bernardino._^<g_
Professor of History, Carleton University, Ottawa._^<g_
Sports Writer, _^<i_Detroit Free Press_^>i_._^<g_
Professor of Russian, Colgate University, Hamilton, N.Y._^<g_
Professor of International Studies, University of Denver, Denver, Colo._^<g_
Professor of Government, University of Texas, Austin._^<g_
Assistant Professor, Marquette University, Milwaukee, Wis._^<g_
Fellow, World Resources Institute and Environment and Policy Institute, Washington, D.C._^<g_
Branch of Astrogeology, United States Geological Survey._^<g_
Vice-President, Sotheby Parke-Bernet, New York City._^<g_
Associate Professor, University of New England, New South Wales, Australia._^<g_
Professor Emeritus of Rumanian Studies, University of London, London._^<g_
Associate Professor of Political Science, Tulane University, New Orleans, La._^<g_
Professor of Fine Arts, Syracuse University, Syracuse, N.Y._^<g_
Art Critic and Historian._^<g_
Associate Curator, American Museum of Natural History, New York City._^<g_
Head, Laboratory of Structural Studies, Department of Immunology, The Babraham Institute, Cambridge, England._^<g_
Professor Emeritus of Biology, Fairleigh Dickinson University, Teaneck, N.J., and Research Associate, Department of Animal Behavior, American Museum of Natural History, New York City._^<g_
Senior Research Associate, Mote Marine Laboratory, Sarasota, Fla., and Professor Emeritus of Biology and Psychology, City University of New York, New York City._^<g_
Professor of History, University of Utah, Sait Lake City._^<g_
Associate Professor, Center for Youth Development and Research, University of Minnesota, Saint Paul._^<g_
Author of _^<i_Bruce Tegner's Complete Book of Self-Defense Judo_^>i_._^<g_
Visiting Physicist, Brookhaven National Laboratory, Upton, N.Y._^<g_
Beers-Bascow Professor of Conservation, Department of Wildlife Ecology, University of Wisconsin, Madison._^<g_
Professor of Surgery, School of Medicine, University of California, Los Angeles._^<g_
Professor, University of California, Los Angeles._^<g_
Author of _^<i_Complete Encyclopedia of Television Programs_^>i_._^<g_
Professor of Slavic Languages, Brown University, Providence, R.I._^<g_
Professor of Chemical Engineering, Director, Energy Laboratory, Massachusetts Institute of Technology, Cambridge._^<g_
Professor of English, University of Minnesota, Duluth._^<g_
Associate Professor of Geography, Carroll College, Waukesha, Wis._^<g_
Professor of Philosophy, City College, City University of New York, New York City._^<g_
Consultant, International Flavors and Fragrances, Inc._^<g_
Professor of Sociology, Pennsylvania State University, University Park._^<g_
Archivist, National Archives._^<g_
Professor of Botany, Northern Kentucky University, Highland Heights._^<g_
Bone Research Laboratory, Nuffield Orthopaedic Hospital, Oxford, England._^<g_
Professor of Zoology, Northern Arizona University, Flagstaff._^<g_
Professor of Music, University of Virginia, Charlottesville._^<g_
Sportswriter, _^<i_Chicago Tribune_^>i_._^<g_
Professor Emeritus, State University of Ghent, Royal Belgian Academy, Brussels._^<g_
Professor of Educational Psychology, University of Calgary, Calgary, Alberta._^<g_
Professor of History, University of California, Santa Cruz._^<g_
Professor of Russian Literature, University of North Carolina, Chapel Hill._^<g_
Professor of City Planning and Urban Design, Harvard University, Cambridge, Mass._^<g_
Professor, School of Justice Administration, University of Louisville, Louisville, Ky._^<g_
Art Historian._^<g_
Clinical Instructor, State College of Optometry, State University of New York, Stony Brook._^<g_
Chairman, and Professor, Department of Geography, University of Nebraska, Omaha._^<g_
Professor of Anthropology, Southern Illinois University, Edwardsville._^<g_
Professor of Political Science, University of Nebraska, Lincoln._^<g_
Associate Professor in History, University of New Hampshire, Durham._^<g_
Professor, School of Medicine, Mercer University, Macon, Ga._^<g_
Performing Arts Editor, _^<i_San Francisco Magazine_^>i_._^<g_
Writer and Broadcaster._^<g_
Professor of English, Emeritus, Boston University, Boston._^<g_
Graduate Research Professor of Anthropology, Emeritus, University of Florida, Gainesville._^<g_
Professor of English, Michigan State University, East Lansing._^<g_
Business Publications Advisor, Former Editor, _^<i_Builder_^>i_ Magazine._^<g_
Senior Minister, Asylum Hill Congregational Church, Hartford, Conn._^<g_
Professor of History, Dalhousie University, Halifax, Nova Scotia._^<g_
Assistant Professor, Division of Continuing Education, University of Utah, and Assistant Professor of Geography, Brigham Young University, Salt Lake City._^<g_
Department of Integrative Biology, University of California, Berkeley._^<g_
Research Professor of Education, University of Illinois, Chicago._^<g_
Assistant Professor of English, University of Michigan, Ann Arbor._^<g_
Assistant Professor of Linguistics and African Languages, University of California, Los Angeles._^<g_
Assistant Professor of Medicine, Mount Sinai School of Medicine, New York City._^<g_
Associate Professor of Asian Studies, University of Illinois, Urbana._^<g_
Associate Professor of English, McGill University, Montreal._^<g_
Art Instructor, Kingsborough Community College, City University of New York, New York City._^<g_
Assistant Professor of Geography and Geology, University of Nevada, Las Vegas._^<g_
Chairman, Division of Critical Care Medicine, and Director, Institute of Critical Care Medicine, University of Southern California, Los Angeles._^<g_
Professor of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles._^<g_
Lecturer in Geography, University of Connecticut, Storrs._^<g_
Associate Professor of Business, Tennessee Technological University, Cookeville._^<g_
Professor Emeritus of Neurology, Mount Sinai Medical School, New York City._^<g_
William Paterson College of New Jersey, Wayne._^<g_
Professor Emeritus, University of Manitoba, Winnipeg._^<g_
Professor and Chairman, Geoscience Department, Jersey City State College, Jersey City, N.J._^<g_
Professor of the History of Medieval Science, Pontifical Institute of Medieval Studies, University of Toronto, Toronto._^<g_
Cornell University, Ithaca, N.Y._^<g_
Physicist, Materials Research Center, Watertown, Mass._^<g_
Associate Director, Roche Institute of Molecular Biology, Nutley, N.J._^<g_
Lecturer in English and General Studies (ret.), Oxford College of Further Education, Oxford, England._^<g_
Professor of Educational Psychology, University of Minnesota, Minneapolis._^<g_
Sterling Professor Emeritus of Comparative Literature, Yale University, New Haven, Conn._^<g_
Professor of Internal Medicine, University of Michigan, Ann Arbor._^<g_
Idaho State Historic Preservation Officer, Idaho State Historical Society, Boise._^<g_
Professor of Linguistics and African Languages, University of California, Los Angeles._^<g_
Professor and Graduate Fellow in Anthropology, New School for Social Research, New York City._^<g_
Department of Political Science, Northern Illinois University, DeKalb._^<g_
Senior Lecturer in Social Anthropology, University of Manchester, Manchester, England._^<g_
Professor of Biology, Blackburn College, Carlinville, Ill._^<g_
Professor of Psychology, University of Colorado, Boulder._^<g_
Professor of History, State University of New York, Albany._^<g_
Author and film producer._^<g_
Columnist and Author, _^<i_The Globe and Mail_^>i_, Toronto._^<g_
Professor of History, University of Arkansas, Fayetteville._^<g_
Associate Professor of Sociology, Pennsylvania State University, University Park._^<g_
Professor of Public Law and Government, Columbia University, New York City._^<g_
Curator, Animal Management Services, New York Zoological Society, Bronx, New York._^<g_
Reader in Plant Pathology, Imperial College Field Station, Silwood Park, Sunninghill, Berkshire, England._^<g_
Assistant to the Director, Federal Judicial Center, Washington, D.C._^<g_
Curator of Dutch and Flemish Painting, National Gallery of Art, Washington, D.C._^<g_
Plant Ecologist, Chesapeake Bay Center for Environmental Studies, Smithsonian Institution, Edgewater, Md._^<g_
Secretary-Treasurer, American Mobilehome Association, Lakewood, Colo._^<g_
Research Scientist, Systematic Entomology Laboratory, U.S. Department of Agriculture, Beltsville, Md._^<g_
Clinical Professor of Surgery, University of Washington School of Medicine, Seattle._^<g_
Chairman, Bureau of Conservation and Environmental Science, Cook College, Rutgers University, New Brunswick, N.J._^<g_
Former publisher of _^<i_Motor Boat and Sailing_^>i_ magazine._^<g_
Research Associate, The Oriental Institute, University of Chicago, Chicago._^<g_
Associate Professor of Geology, University of Georgia, Athens._^<g_
Associate Professor, Graduate School of Architecture, University of Utah, Salt Lake City._^<g_
Associate Dean, School of Music, Baylor University, Waco, Tex._^<g_
Thomas D. Jones Professor of Mathematical Physics, Retired, Princeton University, Princeton, N.J._^<g_
Author of _^<i_Iran, Past and Present_^>i_._^<g_
Assistant Curator of Fishes, Museum of Natural History, University of Kansas, Lawrence._^<g_
Professor Emeritus of Geography, Ohio University, Athens._^<g_
Professor of Comparative Literature, Rutgers University, New Brunswick, N.J._^<g_
Professor of Geology and Geography, University of Massachusetts, Amherst._^<g_
Senior Lecturer, Department of Wool Science, Lincoln College, Canterbury, New Zealand._^<g_
British Military Historian._^<g_
Assistant Professor of Physics, Stanford University, Stanford, Calif._^<g_
Yale School of Law, Research Faculty, Yale University, New Haven, Conn._^<g_
Chairman of the Board, Resource Sciences Corporation, Tulsa, Okla._^<g_
Professor of Communications, University of Texas, Austin._^<g_
Professor of Church History, Harvard University Divinity School, Cambridge, Mass._^<g_
Associate Professor of Philosophy, University of Maryland, College Park._^<g_
Professor of Biology, Lebanon Valley College, Annville, Pa._^<g_
Professor Emeritus of Economics, Northwestern University, Evanston, Ill._^<g_
Professor of Mathematics and Mathematics Education, New York University, New York City._^<g_
Visiting Lecturer, Barnard College, New York City._^<g_
Adjunct Professor, Ohio State University and Ohio Agriculture Research and Development Center, Wooster._^<g_
Associate Professor of Physiology and Biophysics, University of Miami School of Medicine, Miami, Fla._^<g_
Decorative Arts Expert._^<g_
Associate Professor of Oceanography, Marine Sciences Research Center, State University of New York, Stony Brook._^<g_
Professor of English, Boston College, Chestnut Hill, Mass._^<g_
Assistant Professor of Geography, California Polytechnic State University, San Luis Obispo._^<g_
Associate Professor of Geography, University of South Carolina, Columbia._^<g_
Professor of Biology, University of Northern Colorado, Greeley._^<g_
Lecturer in Geology, University of Leicester, Leicester, England._^<g_
Professor of Toxicology, Duquesne University, Pittsburgh, Pa._^<g_
Professor Emeritus of Retail Management, New York University, New York City._^<g_
Co-author of _^<i_Robert Frost: The Later Years, 1938-1963_^>i_._^<g_
Lecturer and Art Historian, Art Gailery of Ontario, Toronto._^<g_
Associate Professor of Geology and Geography, University of Kentucky, Lexington._^<g_
Department of Sociology, George Washington University, Washington, D.C._^<g_
Assistant Professor, Barnard College, Columbia University, New York City._^<g_
Director, Russian and East European Studies, George Washington University, Washington, D.C._^<g_
Assistant Professor, Institute for Molecuiar Virology, St. Louis University School of Medicine, St. Louis._^<g_
Training and Supervising Analyst, Chicago Institute for Psychoanalysis, Chicago._^<g_
Professor of Economics, Oregon State University, Corvallis._^<g_
Robert Dunning Dripps Professor and Chairman, Department of Anesthesia, and Professor of Pharmacology, University of Pennsylvania, Philadelphia._^<g_
Senior Research Scholar, Department of Psychiatry, Rush Institute for Well Being, Rush University, Chicago, Ill._^<g_
Professor Emeritus of Journalism, Syracuse University, Syracuse, N.Y._^<g_
Vice-President for Academic Affairs and Professor of Classics, Mississippi State University, Mississippi State._^<g_
Professor of Geography, University of Alberta, Edmonton._^<g_
Former Editor, _^<i_Canadian Literature_^>i_._^<g_
Life-Fellow of the Royal Society of Arts._^<g_
Associate Professor of Computer Studies and Biology, Hampshire College, Amherst, Mass._^<g_
Professor of English, University of Western Ontario, Canada._^<g_
Associate Professor of Philosophy, University of Texas, Austin._^<g_
Associate Professor of Philosophy, Loyola University of Chicago, Chicago._^<g_
Professor of American Church History, Harvard University, Cambridge, Mass._^<g_
Music Journalist._^<g_
Associate Professor, Lyman Briggs College, Michigan State University, East Lansing._^<g_
Professor of Geography, Rhode Island College, Providence, R.I._^<g_
Professor of Sociology, New York University, New York City._^<g_
Professor of Classics, Brown University, Providence, R.I._^<g_
Horticulturist, Emeritus, Arnold Arboretum, Harvard University, Cambridge, Mass._^<g_
Assistant Professor of Geography, Southern Connecticut State College, New Haven._^<g_
Research Associate, Medical Department, Brookhaven National Laboratory, Upton, N.Y.; Associate Professor of Physiology, Downstate Medical Center, State University of New York._^<g_
Department of Political Science, West Virginia University, Morgantown, W. Va._^<g_
Assistant Professor of English, Columbia University, New York City._^<g_
Editor, _^<i_Vending Times_^>i_._^<g_
Research Civil Engineer, U.S. Geological Survey._^<g_
Professor of Animal Physiology, University of Alberta, Edmonton._^<g_
Author of _^<i_American Roulette: The History and Dilemma of the Vice Presidency_^>i_._^<g_
Professor of History of Religions, Colorado Women's College, Denver._^<g_
Senior Wild Animal Keeper, New York Zoological Society, Bronx, N.Y._^<g_
Professor Emeritus of Chemistry, Brooklyn College, City University of New York, Brooklyn, N.Y._^<g_
Assistant Professor of Therapeutic Radiology, Tufts-New England Medical Center, Boston._^<g_
Associate Professor of History, University of Akron, Akron, Ohio._^<g_
Professional Engineer, CAZ Lab, Baltimore, Md._^<g_
Executive Director, Herpetological Associates, Zoological and Environmental Consultants, Staten Island, N.Y._^<g_
Professor of Mechanical Engineering, University of Alaska, Fairbanks._^<g_
Professor Emeritus of History, City College, City University of New York, New York City._^<g_
Professor of English, Illinois Institute of Technology, Chicago._^<g_
Professor of Chemistry, City University of New York, New York City._^<g_
Sterling Professor of Psychology, Yale University; Head, Psychology Section, Yale Child Study Center, New Haven, Conn._^<g_
Professor of Industrial Management, Clemson University, Clemson, S.C._^<g_
Associate Professor of History, University of Portland, Portland, Oreg._^<g_
Associate Professor, Mechanical Engineering Department, University of Massachusetts, Amherst._^<g_
Professor of German and Comparative Literature, University of Wisconsin, Milwaukee._^<g_
Assistant Professor of Scandinavian Studies, University of Oregon, Eugene._^<g_
Assistant Professor of Art History, University of Wisconsin, Milwaukee._^<g_
Curator of Research, National Museum of Natural History, Smithsonian Institution, Washington, D.C._^<g_
Indigenous life varies greatly among the world's major _^<a!T3715_biomes_^>a_, which are distinguished from each other primarily by _^<a!T7358_climate_^>a_ and vegetation (see _^<a!T25976_plant distribution_^>a_). Climate and vegetation, in turn, support a collection of animal life characteristic of each biome. Even within a particular biome, there are many _^<a!T10583_ecological_^>a_ communities, each with its own plant and animal habitats._^<g_
Although the _^<a!T1718_Arctic_^>a_ region includes much of the biome known as the tundra, life in the Arctic is generally perceived to refer to life on--and under--the polar ice cap. Arctic life, however, encompasses both worlds: from the _^<a!T22932_musk-ox_^>a_, _^<a!T5889_caribou_^>a_, gray _^<a!T35257_wolf_^>a_, and gyrfalcon to the polar _^<a!T3065_bear_^>a_, _^<a!T34380_walrus_^>a_, harp _^<a!T29254_seal_^>a_, and arctic _^<a!T12595_fox_^>a_._^<g_
Almost completely devoid of plants, _^<a!T1448_Antarctica_^>a_ is nevertheless extremely rich and abundant in life. Life on the Antarctic continent thrives because of the sea, where microscopic _^<a!T25969_phytoplankton_^>a_ feed small floating animals called _^<a!T35899_zooplankton_^>a_, which in turn feed a host of fish, birds, and mammals._^<g_
Although the word _^<a!T12450__^<i_forest_^>i__^>a_ could describe any woodland area from the steamy jungles of South America to the coniferous _^<a!T31705_taiga_^>a_ in Siberia, the phrase "forest life" usually brings the temperate-climate habitats to mind. Shown here is a European _^<a!T9242_deciduous_^>a_ woodland, where wild boar and fallow _^<a!T9266_deer_^>a_ still roam among the ancient English _^<a!T24042_oaks_^>a_ and where a myriad assortment of birds, insects, and mammals make their homes._^<g_
Although they cover less than 6% of the earth's land surface, _^<a!T17897_jungles and rain forests_^>a_ are home to almost three-fourths of all known species of plants and animals. Here in the South American rain forest, one can explore the teeming, seething cauldron known as jungle life._^<g_
"Tropical _^<a!T14241_grasslands_^>a_" is how one might define the _^<i_savanna_^>i_, and nowhere is _^<a!T28901_savanna life_^>a_ more enthralling than at a watering hole in Africa. Here, vast herds of _^<a!T35011_wildebeest_^>a_, _^<a!T10851_elephants_^>a_, and _^<a!T13328_gazelles_^>a_ share a precious resource with the black _^<a!T27619_rhinoceros_^>a_, _^<a!T13711_giraffe_^>a_, _^<a!T15836_hippopotamus_^>a_, and _^<a!T19779_lion_^>a_._^<g_
_^<a!T31522_Swamps, marshes, and bogs_^>a_... the distinctions among these aren't always clear, like the brown, muddy water typical to such wetlands. The common defining feature is the _^<a!T34548_water table_^>a_, which is located at, near, or above the surface of the land, encouraging swamp life of wonderful color and variety. Here in the marshlands of the Florida _^<a!T11467_Everglades_^>a_, one can see vast expanses of saw grass, with such exotic animals as the _^<a!T893_alligator_^>a_ and manatee (or _^<a!T30006_Sirenia_^>a_)._^<g_
Although _^<a!T14241_grasslands_^>a_ are found as far south as the tropics and as far north as the tundra, the temperate regions of the earth provide habitats for an abundant grassland life. These habitats--like the North American _^<a!T26441_prairie_^>a_ seen here--are home to a multitude of plants, insects, reptiles, birds, and, of course, mammals, from the smallest pocket _^<a!T22727_mouse_^>a_ to the great North American _^<a!T3783_bison_^>a_._^<g_
Due to the radical climate changes that take place at high altitudes, a single mountain might contain three different biomes. However, _^<a!T22718_mountain life_^>a_ usually refers to the habitats located in the world's great mountain ranges, as depicted here in the _^<a!T15808_Himalayas_^>a_ of central Asia. Predators such as the snow _^<a!T19468_leopard_^>a_ and golden _^<a!T10463_eagle_^>a_ must share a harsh environment with foragers, like the Himalayan _^<a!T16611_ibex_^>a_ and the Alpine _^<a!T34179_vole_^>a_._^<g_
Few regions of the world can rival the great _^<a!T9460_deserts_^>a_ for sheer uninhabitability. Yet in the Sonoran Desert of the southwestern United States, a marvelous array of _^<a!T9461_desert life_^>a_ has adapted to the extreme heat and scarcity of water. As a turkey _^<a!T34254_vulture_^>a_ soars overhead, the desert's reptiles, insects, and mammals all work out their various means of survival._^<g_
_^<a!T17049_Intertidal life_^>a_, along marine coasts such as the North American shores, can be subdivided into four zones. From the lone _^<a!T11955_fiddler crab_^>a_ foraging in the splash zone; to the _^<a!T30228_snails_^>a_, _^<a!T19726_limpets_^>a_, and _^<a!T2799_barnacles_^>a_ of the upper-intertidal zone; to the abundance of _^<a!T1315_anemones_^>a_ and _^<a!T22301_mollusks_^>a_ in the mid- and low intertidal zones, an observer can readily see that this is a habitat rich in variety and concentration of life._^<g_
The temperate _^<a!T14241_grasslands_^>a_ of the world that foster _^<a!T30993_steppe_^>a_ life are home to a broad variety of _^<a!T33417_ungulates_^>a_, _^<a!T27926_rodents_^>a_, and _^<a!T3732_birds_^>a_. On this Eurasian steppe--as on _^<a!T26441_prairies_^>a_ and _^<a!T24864_Pampas_^>a_ around the world--the flora and fauna must adapt not only to distinct wet and dry seasons and a wide range of temperatures, but also to natural disasters such as droughts and fires. Their survival meets its biggest challenge, however, from the encroachment of humans._^<g_
Marked by long, cold winters, _^<a!T33151__^<i_tundra_^>i__^>a_ is the name given to the barren region that encircles the North Pole. This rendering of North American tundra life during the _^<a!T1718_Arctic_^>a_'s brief summer shows a marshy area created from melting snow. _^<a!T3065_Bear_^>a_, _^<a!T22508_moose_^>a_, and _^<a!T10254_ducks_^>a_ are among the wildlife that must eke out an existence in this harsh environment, also home to a variety of _^<a!T22653_mosses_^>a_, _^<a!T19640_lichens_^>a_, and _^<a!T14235_grasses_^>a_._^<g_
The _^<a!T30052_skeletal system_^>a_, which consists mostly of _^<a!T4206_bones_^>a_, has two major jobs. It supports the body--without a skeleton you would be like a jellyfish--and it protects delicate internal organs, such as the brain and heart. The parts of the skeleton that let bones move are called joints. Some joints can be moved freely; others cannot be moved at all. Because bones are living, growing tissue, they must be fed. The outside of a bone is covered with a thin skin, called a periosteum, which holds the tiny blood vessels that carry food to the bone._^<g_See also: _^<a!T30053_skeleton, human_^>a_; _^<a!T30679_spine_^>a_._^<g_
The _^<a!T7163_circulatory system_^>a_ includes the _^<a!T15353_heart_^>a_, _^<a!T3984_blood_^>a_, and blood vessels. Its function is to move blood throughout the body. Many thousands of miles of vessels--_^<a!T1911_arteries_^>a_, _^<a!T33815_veins_^>a_, and _^<a!T5780_capillaries_^>a_--travel through the body, supplying oxygenated blood to the body's tissues and organs. Blood acts as a transport vehicle, carrying nutrients and oxygen to cells. Blood also picks up waste materials from the cells, carries immune cells throughout the body, and picks up and carries heat from the inside of the body out to the skin, where it is released into the air._^<g_
The _^<a!T23398_nervous system_^>a_ is the most highly developed and most complex of all the systems of the human body. It consists of the _^<a!T4569_brain_^>a_, _^<a!T30675_spinal cord_^>a_, neurons (or nerve cells), and _^<a!T29401_sense_^>a_ organs (such as the eyes and ears). It obtains information about the outside environment. It informs us when we are tired or hungry or too hot or too cold. It regulates the functions of the other systems of the body. It is responsible for our thinking, our behavior, our feelings and attitudes, our likes and dislikes._^<g_See also: _^<a!T23428_neurology_^>a_; _^<a!T23426_neurobiology_^>a_._^<g_
The _^<a!T20321_lymphatic system_^>a_--an extensive network of vessels and nodes--picks up a fluid called lymph from the spaces between cells and empties it into blood vessels near the heart. The lymphatic system plays a central role in fighting infectious agents such as bacteria, viruses, and molds. It contains specialized cells that trap foreign bacteria, preventing them from entering the blood. The lymph nodes also are important sites of lymphocyte formation. Lymphocytes are the cells that manufacture antibodies. During periods of active antibody formation, the lymph nodes often become swollen and tender._^<g_
To function, the cells of the body need water and fuel to burn. The fuel comes from the foods we eat and drink. However, food cannot be used directly as fuel. It must be broken down and changed. This process of converting food to fuel is called digestion and takes place in the _^<a!T9656_digestive system_^>a_. Digestion begins in the mouth and is continued in the _^<a!T31104_stomach_^>a_ and _^<a!T17051_intestines_^>a_. Digested materials pass through the intestinal cells into the bloodstream. Wastes are stored in the large intestine until they pass out of the body as bowel movements._^<g_
The cells in your body must have oxygen to produce energy, and they must get rid of the waste gas carbon dioxide that forms when energy is produced. The _^<a!T27552_respiratory system_^>a_ performs these functions. When you inhale, air moves through your nose and down into your lungs. Oxygen from the air enters the blood through the thin walls of air sacs in the _^<a!T20262_lungs_^>a_. Carbon dioxide moves from the blood into the air sacs. When you exhale, the oxygen-poor, carbon dioxide-rich air leaves your body. Muscles in the chest wall and a muscle called the diaphragm, which separates the chest from the abdomen, aid in respiration._^<g_See also: _^<a!T27553_respiratory system disorders_^>a_._^<g_
The hormonal, or _^<a!T11008_endocrine system_^>a_ produces powerful chemical messengers called _^<a!T16141_hormones_^>a_, which are released directly into the bloodstream. Hormones influence the actions of body cells; for example, _^<a!T32441_thyroxine_^>a_ produced by the _^<a!T32439_thyroid gland_^>a_ controls metabolism. Some endocrine glands are common to all humans, including the _^<a!T25929_pituitary_^>a_, _^<a!T32439_thyroid_^>a_, _^<a!T24975_parathyroid_^>a_, _^<a!T24882_pancreas_^>a_, and _^<a!T319_adrenal glands_^>a_. But males and females have different sex glands. Males have testes, which produce the hormone testosterone. Secondary sex characteristics, including beard growth and voice change, are influenced by testosterone._^<g_See also: _^<a!T11009_endocrine system, diseases of the_^>a_ and _^<a!T29520_sex hormones_^>a_._^<g_
The hormonal, or _^<a!T11008_endocrine system_^>a_ produces powerful chemical messengers called _^<a!T16141_hormones_^>a_, which are released directly into the bloodstream. Hormones influence the actions of body cells; for example, _^<a!T32441_thyroxine_^>a_ produced by the _^<a!T32439_thyroid gland_^>a_ controls metabolism. Some endocrine glands are common to all humans, including the _^<a!T25929_pituitary_^>a_, _^<a!T32439_thyroid_^>a_, _^<a!T24975_parathyroid_^>a_, _^<a!T24882_pancreas_^>a_, and _^<a!T319_adrenal glands_^>a_. But females and males have different sex glands. Females have ovaries, which produce the hormone estrogen. Secondary sex characteristics, including breast enlargement, are influenced by estrogen._^<g_See also: _^<a!T11009_endocrine system, diseases of the_^>a_ and _^<a!T29520_sex hormones_^>a_._^<g_
The process of _^<a!T27529_reproduction_^>a_ involves the creation of a new human being. It begins when a male's reproductive cell, called a _^<a!T30641_sperm_^>a_, joins with a female's reproductive cell, called an ovum (or _^<a!T10673_egg_^>a_). In a male, the reproductive structures include the two testes, which produce and store sperm. The sperm are transported through narrow tubes to the penis, which is the external reproductive organ of the male. The penis is used for both transporting sperm into the female reproductive system and eliminating urine._^<g_See also: _^<a!T29529_sexual intercourse_^>a_._^<g_
The process of _^<a!T27529_reproduction_^>a_ involves the creation of a new human being. It begins when a male's reproductive cell, called a _^<a!T30641_sperm_^>a_, joins with a female's reproductive cell, called an ovum (or _^<a!T10673_egg_^>a_). In a female, the reproductive structures include the two ovaries, which produce the ovum, and the _^<a!T33594_uterus_^>a_, which is where babies grow until they are ready to be born. Each ovary is connected to the top of the uterus by a fallopian tube. At the bottom of the uterus, a canal-like structure called the vagina opens to the outside of the body._^<g_See also: _^<a!T29529_sexual intercourse_^>a_._^<g_
There are 22 bones in the human _^<a!T30078_skull_^>a_, 21 of which are so firmly united that movement between them is impossible. One bone, the mandible, or lower jawbone, is hinged to the rest of the skull and is independent and movable. The cranium, the protective covering of the brain, is composed of eight bones. At birth the edges of these bones are not yet interlocked but are held together by connective tissue strips called sutures. As a child matures, the sutures fuse and the bones become completely hard and immovable. The remaining bones in the skull are thin, delicate facial bones._^<g_
The _^<a!T31987_teeth_^>a_ are solid structures, made hard by the embedding of calcium, phosphorus, magnesium, and other mineral salts in an organic material. Their bases, or roots, are firmly anchored in bony sockets in the upper and lower jaws. Between each tooth root and the jaw is the periodontal membrane, a layer of soft tissue that holds the tooth in place and acts as a cushion to lessen the force of impact that takes place in chewing._^<g_
The parts of the skeleton that let bones move are called _^<a!T17728_joints_^>a_ or, more scientifically, articulations. Bones fit together at joints and are held fast by tough bands of connective tissue called _^<a!T19673_ligaments_^>a_ or _^<a!T6039_cartilage_^>a_. Some joints can be moved freely; others cannot be moved at all. Many are lubricated with a liquid called synovial fluid to help them move._^<g_
The muscular system consists of some 700 different _^<a!T22901_muscles_^>a_. By alternately contracting and relaxing, these muscles account for all body motion. Some muscles move the limbs; others open and close the eyelids; and still others help us digest our food. Even a seemingly simple task such as taking one step involves about 200 muscles! Some muscles lift and move your leg forward, while others in the back, chest, and abdomen help you keep from losing your balance during the motion._^<g_See also: _^<a!T3709_biological locomotion_^>a_._^<g_
Skeletal muscle--the most numerous of the three basic _^<a!T22901_muscle_^>a_ types--is striated, or made up of light and dark cross-striped bands. Smooth muscle does not show any cross stripes. Cardiac muscle, although it resembles smooth muscle in that it contracts automatically, has a certain similarity to skeletal muscle, since its fibers have a cross-striped pattern. Cardiac muscle contracts more slowly than skeletal muscle, however, and takes more time to recover from contraction, so they do not give a sustained contraction._^<g_
The _^<a!T15353_heart_^>a_ is a powerful muscular pump that pushes _^<a!T3984_blood_^>a_ through the many miles of blood vessels. It is divided into four parts called chambers. The two upper chambers, or atria, act as receptacles for blood as it enters the heart. The two lower chambers, or ventricles, act as pumps to force blood out of the heart. A wall called the septum divides the heart into a left half and a right half. The opening between the auricle and corresponding ventricle on each side is guarded by a valve designed to prevent blood from flowing backwards. Two other valves guard the exits from the ventricles._^<g_See also: _^<a!T1539_aorta_^>a_; _^<a!T8188_coronary artery_^>a_._^<g_
Muscle contraction is controlled by the nervous system. A typical nerve cell, or neuron, has a cell body, containing a nucleus, and two kinds of processes: dendrites and axons. Dendrites are short and often branch repeatedly, forming a sort of bush around the cell body. The axon is usually long and very thin. Each neuron has only one axon. It may extend for a distance of only a few centimeters or it may run all the way from the spinal cord to the tip of a toe or finger. Motor, or efferent, neurons transmit impulses from the brain or spinal cord to muscles and other body structures. Sensory, or afferent, neurons transmit impulses from various parts of the body to the brain or spinal cord._^<g_See: _^<a!T23398_nervous system_^>a_; _^<a!T23428_neurology_^>a_; _^<a!T23426_neurobiology_^>a_; _^<a!T23436_neurotransmitter_^>a_; _^<a!T27417_reflex_^>a_._^<g_
The _^<a!T4569_brain_^>a_ is composed of several different parts that work together. The lowest part, a continuation of the spinal cord, is the brain stem. It consists of the medulla oblongata, pons, and midbrain. It controls respiration, heartbeat, and other involuntary actions, and serves as a pathway for nerve fibers. The cerebellum controls body movement and balance. The largest part, weighing four-fifths of the brain's total weight, is the cerebrum, where thinking, memory, feelings, and sensations are centered. It is made up of two cerebral hemispheres, each of which is divided into four lobes._^<g_
The _^<a!T16371_human body_^>a_ is a wondrously complex structure composed of billions of _^<a!T6298_cells_^>a_. Cells are joined to make _^<a!T32566_tissue_^>a_, and different kinds of tissue are combined in the body's organs. A group of organs working together is called a system. Each system has specific jobs, but together they make it possible for the body to move, grow, think, reproduce, respond to the environment, and carry out many other functions._^<g_See also: _^<a!T1232_anatomy_^>a_._^<g_
Most of the liquid waste produced by the body is removed by the urinary system as _^<a!T33557_urine_^>a_. The two _^<a!T18338_kidneys_^>a_, the _^<a!T3878_bladder_^>a_, and the tubes that connect them are the structures of the urinary system. The kidneys remove wastes, such as excess water and salts, from the blood. After the waste liquid is processed in the kidney, it moves through the connecting tubes into the bladder. The bladder stores the urine until it is eliminated from the body._^<g_See _^<a!T11503_excretory system_^>a_._^<g_
Blood enters a _^<a!T18338_kidney_^>a_ through its renal artery. The artery empties into ever-smaller arterioles, which conduct the blood to the tightly looped capillaries that make up the glomeruli within the Bowman's capsules. The walls of the capillaries are so thin that chemicals can pass from the blood through the capillary walls and into the Bowman's capsules. From each capsule, the mixture moves into the nephron's tubule. As the mixtures passes through the long tubule, useful substances are reabsorbed back into the blood. The remaining wastes, called urine, flow into collecting ducts and hence into the renal pelvis and the ureter. The cleansed blood leaves the kidney through the renal vein._^<g_See also: _^<a!T18336_kidney disease_^>a_._^<g_
There were actually four attempts to fly on December 17, 1903, at Kitty Hawk, North Carolina. In the first, Orville _^<a!T35439_Wright_^>a_ piloted the plane, which flew 120 feet. Later that day, Wilbur flew the plane the longest distance, 852 feet, and remained airborne for 59 seconds. In 1948 the plane flown at Kitty Hawk was returned from the Science Museum in London to its permanent home at the National Air and Space Museum in Washington, D.C._^<g_See also: _^<a!T2331_aviation_^>a_; _^<a!T12245_flight_^>a_; _^<a!T549_aircraft_^>a_._^<g_
The route of Charles _^<a!T19745_Lindbergh_^>a_'s historic flight took him over Nova Scotia, Newfoundland, and Ireland, a distance of about 3,600 miles. He brought neither a parachute nor a radio, preferring to use the weight for extra fuel. However, he did bring along his own personal fuel--five sandwiches and a quart of water. Lindbergh landed at Le Bourget, France, on May 21 at 10:22 P.M. (Paris time), where he received an enthusiastic welcome._^<g_See also: _^<a!T2331_aviation_^>a_._^<g_
Human-powered _^<a!T12246_flight_^>a_ took off in 1977 with the 6 1/2 minute ascent of the _^<i_Gossamer Condor_^>i_, piloted by Bryan Allen and built by Paul _^<a!T20429_MacCready_^>a_. This plane was created from cardboard, piano wire, aluminum tubing, and Mylar plastic. The _^<i_Gossamer Albatross_^>i_, again piloted by Allen and built by MacCready, crossed the English Channel in two hours and forty-nine minutes on June 12, 1979. The _^<i_Daedalus_^>i_, built by a team at the Massachusetts Institute of Technology in Cambridge, MA, made the trip from Crete to the Aegean island of Santorini in four hours on April 23, 1988, sometimes flying just yards above the water and powered only by Kanellos Kanellopoulos' legs._^<g_See also: _^<a!T549_aircraft_^>a_._^<g_
Associate Professor of Medical Psychology, Department of Psychiatry, Duke University Medical Center, Durham N.C._^<g_
Director of Design and Engineering, McCormick Place Expansion. Former Senior Vice-President, United Airlines._^<g_
Professor and Chair, Asian American Studies Program, University of California, Santa Barbara._^<g_
Professor of Near East Studies, Wayne State University, Detroit, Mich._^<g_
Director of Pharmaceutical Services, College of Pharmacy, University of Iowa, Iowa City._^<g_
Professor and Chair, Department of Psychiatry, University of Toronto, Ontario Canada._^<g_
Professor of Biology, Baruch College, City University of New York, New York City._^<g_
Professor of Geography and Environmental Studies, University of Colorado at Colorado Springs._^<g_
Associate Professor, Center for the Study of Higher Education and Postsecondary Education, University of Michigan, Ann Arbor._^<g_
Author of _^<i_Man-Made Minds and Complexity_^>i_._^<g_
Professor of Plant Genetics, Department of Agronomy, University of Illinois, Urbana._^<g_
Professor of Physics, University of Maryland, College Park._^<g_
Professor of Geology, Smith College, Northampton, Mass._^<g_
Assistant Professor of Sociology, Southern Illinois University, Carbondale._^<g_
Writer. Author of _^<i_Hearts of Lions_^>i_ and _^<i_Cyclist's Sourcebook_^>i_._^<g_
Division of Human Genetics and Molecular Biology, The Children's Hospital of Philadelphia, Philadelphia, Pa._^<g_
Dean, School of Social Sciences, Tartu University, Tartu, Estonia._^<g_
Professor of Anthropology, University of Missouri, Columbia._^<g_
Writer. Author of _^<i_Latinos: A Biography of the People_^>i_._^<g_
Professor of Medicine and Physiology, School of Medicine, University of Rochester, Rochester, N.Y._^<g_
Professor of English, Emeritus, University of Massachusetts, Amherst._^<g_
Santa Fe Institute, Santa Fe, N.Mex._^<g_
Department of Sociology and Anthropology, Towson State University, Towson, Md._^<g_
Clinical Associate Professor of Medicine, Baylor College of Medicine, Houston Tex._^<g_
Writer._^<g_
Co-director, Greenberg Center for Skeletal Dysplasias; Associate Professor of Neurology, Medicine, Neurological Surgery and Pediatrics, Johns Hopkins Center for Medical Genetics, Baltimore, Md._^<g_
Columbia Electronic Music Center, Columbia University, New York City._^<g_
Department of Chemistry, University of California, San Diego._^<g_
United States Naval Observatory, Flagstaff, Ariz._^<g_
Professor of Sociology, State University of New York, Stonybrook._^<g_
Professor of English, Pennsylvania State University, University Park._^<g_
Department of Cardiothoracic Surgery, Wayne State University, Detroit, Mich._^<g_
Professor of Religion, Miami University, Osford, Ohio._^<g_
Professor of Psychology, Wesleyan University, Middletown, Conn._^<g_
Assistant Professor of Surgery, University of Utah, Salt Lake City._^<g_
Artificial Heart Research Laboratory, University of Utah, Salt Lake City._^<g_
Professor of Art, University of South Carolina, Columbia._^<g_
Department of Psychology, University of Victoria, British Columbia._^<g_
Associate Professor of Political Science, University of Oklahoma, Norman._^<g_
Internet Consulting Group, Ottawa, Canada._^<g_
Department of Molecular and Cellular Biology, Harvard University, Cambridge, Mass._^<g_
Research Fellow, Rock Art, Department of Archaeology, University of Southampton, Highfield, England._^<g_
Professor of Political Science, University of the South, Sewanee, Tenn._^<g_
Writer._^<g_
Cardiology Fellow, New York University Medical Center, New York City._^<g_
Director of Cardiopulmonary Transplantation and Cardiovascular Research, Texas Heart Institute, Houston._^<g_
Professor, New School of Social Research, New York City._^<g_
Editor, _^<i_TV Digest_^>i_._^<g_
Allergist._^<g_
Professor and Chairman, Emeritus, Department of Psychiatry, University of Kansas Medical School, Kansas City._^<g_
Department of Political Science, Furman University, Greenville, S.C. Coauthor of _^<i_Understanding Contemporary Africa_^>i_._^<g_
Department of History, Franklin and Marshall College, Lancaster, Pa._^<g_
President, PetroTech Alaska Inc._^<g_
Postdoctoral Fellow, Yale University School of Medicine, New Haven, Conn._^<g_
Solar and Astrophysics Laboratory, Lockheed Martin, Palo Alto, Calif._^<g_
Department of Physics and Professor of Astronomy, Ohio State University, Columbus._^<g_
Department of Physiology, City University Medical School, New York City._^<g_
Writer and Editor. Author of _^<i_Unser, An American Family Portrait_^>i_._^<g_
Department of Psychology, University of Lethbridge, Alberta, Canada._^<g_
Gemological Institute of America._^<g_
Bookhaven National Laboratory._^<g_
Washington University, St. Louis, Mo._^<g_
Author of _^<i_The Complete Guide to Modern Dance_^>i_._^<g_
Former Chair, Department of Drama, University of Alberta, Edmonton._^<g_
Assistant Clinical Professor of Orthopedic Surgery, Mount Sinai School of Medicine, New York City._^<g_
Assistant Professor, Department of Political Science, University of San Diego, Calif._^<g_
Professor of Sociology, Syracuse University, Syracuse, N.Y._^<g_
Department of Geography, University College, Dublin, Ireland._^<g_
Associate Professor, University of Kentucky, Lexington._^<g_
Shadek Humanities Professor, Franklin and Marshall College, Lancaster, Pa._^<g_
Professor of Sociology, Bryn Mawr College, Bryn Mawr, Pa._^<g_
Department of Psychology, Barnard College, New York City._^<g_
Writer._^<g_
Fellow, Centre for International Studies of the London School of Economics._^<g_
Effie Marie Cain Regents Chair in Art, University of Texas, Austin._^<g_
Department of Astrophysical, Planetary, and Atmospheric Sciences, University of Colorado, Boulder._^<g_
Professor Emeritus, Rutgers University, New Brunswick, N.J._^<g_
Administrative Director, American Ambulance Association._^<g_
Professor of Music, Montclair State College, Montclair, N.J._^<g_
Department of Cardiothoracic Surgery, Wayne State University, Detroit, Mich._^<g_
Institute of Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada._^<g_
Professor Emeritus of American Music, University of Massachusetts, Boston._^<g_
Curator, Department of Africa, Oceania and the Americas, The Art Institute of Chicago, Ill._^<g_
Department of Psychology, University of Lethbridge, Alberta, Canada._^<g_
Department of Physics, Florida Atlantic University, Boca Raton, Fla._^<g_
Journalist and Writer. Author of _^<i_Australia and the Australians_^>i_._^<g_
Assistant Professor, Department of Neurology, University of Michigan Medical Center, Ann Arbor._^<g_
Section Head, Nutrition and Endocrinology, American Health Foundation, Valhalla, N.Y._^<g_
University of Michigan Medical Center, Ann Arbor._^<g_
M. D. Anderson Cancer Center, University of Texas, Houston._^<g_
Writer._^<g_
Director of Pediatric Nephrology, Greenville Hospital System, Greenville, S.C._^<g_
Gastrointestinal and Medical Oncology Units, Massachusetts General Hospital, Boston, Mass._^<g_
Professor of English, University of Alabama, Tuscaloosa._^<g_
Midwest Director, Organization of Parents Through Surrogacy._^<g_
Director, Carlson Gallery, University of Bridgeport, Conn._^<g_
Department of Political Science, Miami University, Oxford, Ohio._^<g_
Freelance Television Critic; Editor and Reporter, _^<i_Philadelphia Daily News_^>i_._^<g_
Professor of Biology, Central Michigan University, Mount Pleasant, Mich._^<g_
Department of Drama and Theater, Queens College, Flushing, N.Y._^<g_
Bowling Air Force Base, Washington, D.C._^<g_
Children's Hospital of Philadelphia, Philadelphia, Pa._^<g_
National Marine Fisheries Service, Silver Springs, Md._^<g_
Department of English, University of British Columbia, Vancouver._^<g_
Science Writer. Author of _^<i_Communications in the World of the Future_^>i_._^<g_
American Foundation for the Blind, New York City._^<g_
Director, Programs and Policy Research, American Foundation for the Blind, New York City._^<g_
American Radio Relay League, Newington, Conn._^<g_
Department of Psychology, University of Illinois, Champaign-Urbana._^<g_
Former Professor of Persian, University of Pennsylvania, Philadelphia._^<g_
Department of Neurology, Minneapolis Veterans Administration Medical Center, Minneapolis, Minn._^<g_
Boston, Mass._^<g_
Park Ranger, Inyo National Forest, Calif._^<g_
Department of Otolaryngology, University of Minnesota Medical School, Minneapolis._^<g_
Professor of Mathematics, City College of New York, New York City._^<g_
Wisconsin Heritages, Inc., Milwaukee, Wis._^<g_
Professor of Cultural and Educational Policy, College of Education, University of Illinois, Champaign-Urbana._^<g_
Department of Physics, Haverford College, Haverford, Pa._^<g_
International Institute of Parasitology, St. Albans, Hertfordshire, England._^<g_
Professor, Department of Civil Law, University of Edinburgh, Scotland._^<g_
Vice President, Publications, Insurance Information Institute, New York City._^<g_
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Associate Professor of Neurology and Director of Neuromuscular Program, University of Utah Medical Center, Salt Lake City._^<g_
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Neuromuscular Program Manager, University of Utah Medical Center, Salt Lake City._^<g_
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Professor of Psychology, Northwestern University, Evanston, Ill._^<g_
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Professor of Geography, Manchester Community-Technical College, Manchester, Conn._^<g_
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Assistant Professor of Anthropology, Bryn Mawr College, Bryn Mawr, Pa._^<g_
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Arbortext, Ann Arbor, Mich._^<g_
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Consultant and Writer on Psychology._^<g_
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Professor of Anthropology, San Francisco State University, San Francisco, Calif._^<g_
_^<n__^<b_Diameter:_^>b_ 1.39 million km; 860,000 mi_^<n__^<b_Density (g/cu cm):_^>b_ 1.409_^<n__^<b_Temperature:_^>b_ surface: 5,770 K (9,926 deg F); core: 15,000,000 K (27,000,000 deg F) _^<n__^<b_Magnetic field:_^>b_ average: 1 to 2 gauss; in sunspots: 1,000 to 4,000 gauss_^<n__^<b_Rotation period (in Earth time):_^>b_ at equator: 25.53 days; at poles: 36.61 days_^<n__^<b_Number of planets:_^>b_ 9_^<n__^<b_Distance from the Earth (light years):_^>b_ about 8 minutes_^<n__^<b_Distance to nearest star (light years):_^>b_ 4.3_^<n__^<g_
_^<n__^<b_Distance from Sun (mean):_^>b_ 57.9 million km.; 36.0 million mi.; 0.38 AU._^<n__^<b_Closest approach to Earth:_^>b_ 94.7 million km.; 57.0 million mi._^<n__^<b_Length of year (in Earth time):_^>b_ 87.97 days_^<n__^<b_Average orbital speed:_^>b_ 47.89 km/sec; 29.74 mi/sec._^<n__^<b_Rotation period (in Earth time):_^>b_ 58.65 days._^<n__^<b_Mass (Earth=1):_^>b_ 0.054_^<n__^<b_Density (g/cu cm):_^>b_ 5.42_^<n__^<b_Diameter at equator:_^>b_ 4,878 km; 3,031 mi._^<n__^<b_Number of known moons:_^>b_ 0_^<n__^<g_
_^<n__^<b_Distance from Sun (mean):_^>b_ 108.2 million km; 67.0 million mi; 0.72 AU_^<n__^<b_Closest approach to Earth:_^>b_ 44.4 million km; 25.7 million mi_^<n__^<b_Length of year (in Earth time):_^>b_ 224.7 days_^<n__^<b_Average orbital speed:_^>b_ 35.3 km/sec; 21.75 mi/sec_^<n__^<b_Rotation period (in Earth time):_^>b_ 243 days (retrograde)_^<n__^<b_Mass (Earth=1):_^>b_ 0.815_^<n__^<b_Density (g/cu cm):_^>b_ 5.2_^<n__^<b_Diameter at equator:_^>b_ 12,104 km; 7,517 mi_^<n__^<b_Number of known moons:_^>b_ 0_^<n__^<g_
_^<n__^<b_Distance from Sun (mean):_^>b_ 149.6 million km; 93.0 million mi; 1.00 AU_^<n__^<b_Length of year (in Earth time):_^>b_ 365.26 days_^<n__^<b_Average orbital speed:_^>b_ 29.79 km/sec; 18.50 miles/sec_^<n__^<b_Rotation period (in Earth time):_^>b_ 24 hr 56 min 4 sec_^<n__^<b_Mass (Earth=1):_^>b_ 1.00_^<n__^<b_Density (g/cu cm):_^>b_ 5.51_^<n__^<b_Diameter at equator:_^>b_ 12,756 km; 7,921 miles_^<n__^<b_Number of known moons:_^>b_ 1_^<n__^<g_
_^<n__^<b_Distance from Sun (mean):_^>b_ 227.9 million km; 141.6 million mi; 1.52 AU_^<n__^<b_Closest approach to Earth:_^>b_ 55.7 million km; 34.6 million mi_^<n__^<b_Length of year (in Earth time):_^>b_ 687.0 days_^<n__^<b_Average orbital speed:_^>b_ 24.13 km/sec; 14.98 mi/sec_^<n__^<b_Rotation period (in Earth time):_^>b_ 24 hr 37 min 23 sec_^<n__^<b_Mass (Earth=1):_^>b_ 0.107_^<n__^<b_Density (g/cu cm):_^>b_ 3.9_^<n__^<b_Diameter at equator:_^>b_ 6,794 km; 4,222 mi_^<n__^<b_Number of known moons:_^>b_ 2_^<n__^<g_
_^<n__^<b_Distance from Sun (mean):_^>b_ 778.3 million km; 483.3 million mi; 5.2 AU_^<n__^<b_Closest approach to Earth:_^>b_ 628.8 million km; 390.7 million mi_^<n__^<b_Length of year (in Earth time):_^>b_ 11.86 years_^<n__^<b_Average orbital speed:_^>b_ 13.06 km/sec; 8.11 mi/sec_^<n__^<b_Rotation period (in Earth time):_^>b_ 9 hr 50 min 30 sec_^<n__^<b_Mass (Earth=1):_^>b_ 817.9_^<n__^<b_Density (g/cu cm):_^>b_ 1.32_^<n__^<b_Diameter at equator:_^>b_ 142,984 km; 88,846 mi_^<n__^<b_Number of known moons:_^>b_ 16_^<n__^<g_
_^<n__^<b_Distance from Sun (mean):_^>b_ 1,429.4 million km; 886.7 million mi; 9.54 AU_^<n__^<b_Closest approach to Earth:_^>b_ 1,277.4 million km; 793.7 million mi_^<n__^<b_Length of year (in Earth time):_^>b_ 29.46 years_^<n__^<b_Average orbital speed:_^>b_ 9.64 km/sec; 5.99 mi/sec_^<n__^<b_Rotation period (in Earth time):_^>b_ 10 hr 14 min_^<n__^<b_Mass (Earth=1):_^>b_ 95.14_^<n__^<b_Density (g/cu cm):_^>b_ 0.69_^<n__^<b_Diameter at equator:_^>b_ 120,536 km; 74,897 mi_^<n__^<b_Number of known moons:_^>b_ 22_^<n__^<g_
_^<n__^<b_Distance from Sun (mean):_^>b_ 2,871.0 million km; 1,784.0 million mi; 19.218 AU_^<n__^<b_Closest approach to Earth:_^>b_ 2,587.0 million km; 1,607.0 million mi_^<n__^<b_Length of year (in Earth time):_^>b_ 84.01 years_^<n__^<b_Average orbital speed:_^>b_ 6.81 km/sec; 4.23 mi/sec_^<n__^<b_Rotation period (in Earth time):_^>b_ 23 hr 15 min (retrograde)_^<n__^<b_Mass (Earth=1):_^>b_ 14.58_^<n__^<b_Density (g/cu cm):_^>b_ 1.21_^<n__^<b_Diameter at equator:_^>b_ 51,118 km; 31,763 mi_^<n__^<b_Number of known moons:_^>b_ 15_^<n__^<g_
_^<n__^<b_Distance from Sun (mean):_^>b_ 4,504.0 million km; 2,798.7 million mi; 30.06 AU_^<n__^<b_Closest approach to Earth:_^>b_ 4,310.0 million km; 2,680.0 million mi_^<n__^<b_Length of year (in Earth time):_^>b_ 164.8 years_^<n__^<b_Average orbital speed:_^>b_ 6.81 km/sec; 4.23 mi/sec_^<n__^<b_Rotation period (in Earth time):_^>b_ 16 hr 3 min_^<n__^<b_Mass (Earth=1):_^>b_ 17.22_^<n__^<b_Density (g/cu cm):_^>b_ 1.67_^<n__^<b_Diameter at equator:_^>b_ 49,528 km; 30,775 mi_^<n__^<b_Number of known moons:_^>b_ 8_^<n__^<g_
_^<n__^<b_Distance from Sun (mean):_^>b_ 5,913.5 million km; 3,674.5 million mi; 39.5 AU_^<n__^<b_Closest approach to Earth:_^>b_ 4,290.0 million km; 2,670.0 million mi_^<n__^<b_Length of year (in Earth time):_^>b_ 248.8 years_^<n__^<b_Average orbital speed:_^>b_ 4.74 km/sec; 2.94 mi/sec_^<n__^<b_Rotation period (in Earth time):_^>b_ 6 days 9 hr_^<n__^<b_Mass (Earth=1):_^>b_ 0.0026_^<n__^<b_Density (g/cu cm):_^>b_ 2.1_^<n__^<b_Diameter at equator:_^>b_ 2,340 km; 1,454 mi_^<n__^<b_Number of known moons:_^>b_ 1_^<n__^<g_
The sight of a sports car, the _^<a!T31882_taste_^>a_ of lemon, the sounds of a band, the _^<a!T31882_smell_^>a_ of newly cut grass, the feel of silk--these impressions result from the ability of _^<a!T29401_sense_^>a_ organs to respond to stimuli. The _^<a!T11561_eyes_^>a_ respond to light; the _^<a!T32695_tongue_^>a_ to taste; the _^<a!T10471_ears_^>a_ to sounds; the _^<a!T23903_nose_^>a_ to smell; the _^<a!T30063_skin_^>a_ to touch, pain, pressure, heat, and cold. The sense organs originate nerve impulses that travel along nerve pathways to the brain, which interprets the messages. Not until the messages reach the brain do we actually see, hear, taste, and so on._^<g_See also: _^<a!T25391_perception_^>a_._^<g_
Until the 1950s, the realm of "outer space" belonged to earth-bound astronomers, physicists, and science fiction writers. In the scant half-century since the age of _^<a!T30541_space exploration_^>a_ began, we have traveled far--from the most rudimentary satellites, to landing men on the moon, to probing the outermost reaches of our solar system._^<g_See also: _^<a!T30545_space programs, national_^>a_._^<g_
After the Soviet Union stunned the world by launching _^<i__^<a!T30766_Sputnik_^>a__^>i_, the United States launched itself into the space race. The first effort at sending an astronaut into orbit was dubbed the _^<a!T21675_Mercury program_^>a_, whose exploits were memorialized in Tom Wolfe's book _^<i_The Right Stuff_^>i_. With severe weight and size restrictions, the Mercury capsule was barely large enough to hold a single astronaut, packed as it was with navigation, communication, and emergency equipment. _^<g_
NASA's _^<a!T13373_Gemini program_^>a_ was the bridge between _^<a!T21675_Mercury_^>a_, the first U.S. manned space program, and _^<a!T1572_Apollo_^>a_, which would carry astronauts to the moon. The main goals of Gemini were increased endurance and sophisticated docking techniques, both of which were achieved in a series of 10 two-man missions. The Gemini capsule was a scaled-up version of its Mercury predecessor, with 50% more cabin space and twice as much weight._^<g_
The third and final phase of _^<a!T23154_NASA_^>a_'s quest to put a man on the moon was realized with the _^<a!T1572_Apollo program_^>a_. The first manned Apollo flight took place in 1968; nine months and four flights later, Neil _^<a!T1839_Armstrong_^>a_ made his historic "one small step for a man." The Command and Service Module (CSM), which took astronauts to the moon and back, was actually two separate entities: the Command Module, which carried the crew; and the Service Module, which housed the main engine, fuel cells, and other support equipment._^<g_
Hitched to the nose of the _^<i__^<a!T1572_Apollo_^>a__^>i_ Command and Service Module (CSM) during the long flight from Earth, the _^<a!T20249_Lunar Excursion Module_^>a_ (LEM) was the actual vehicle that carried astronauts to the surface of the moon. The LEM was built in two sections: the descent stage, which contained the main engine and landing gear; and the ascent stage, which carried the crew back to the orbiting CSM._^<g_
_^<i_Vostok_^>i_ and _^<i_Voskhod_^>i_ are variations of a Russian word that means "moving upward"--and move upward they did. These were the names of the early manned space programs of the Soviet Union. _^<a!T34231_Vostok_^>a_, which carried Yuri Gagarin into orbit as the first human in space, used a 7.5-foot sphere capable of carrying only one person. _^<a!T34230_Voskhod_^>a_ could carry three, although to do so meant stripping the spacecraft of some safety equipment._^<g_
Since 1967, _^<a!T30539_Soyuz_^>a_ has been the Soviet (now Russian) space program for taking cosmonauts into space. At first, this successor to the _^<a!T34231_Vostok_^>a_ and _^<a!T34230_Voskhod_^>a_ programs carried out sophisticated docking maneuvers and space-walk missions in anticipation of a Soviet attempt to go to the moon. The success of the U.S. _^<a!T1572_Apollo_^>a_ mission, however, compelled a shift in Soviet space policy. Since 1971, the three-sectioned Soyuz spacecraft have been used primarily to ferry crews and supplies between Earth and orbiting space stations._^<g_
Seven different _^<a!T30547_space stations_^>a_ bore the name _^<a!T28618__^<i_Salyut_^>i__^>a_ during the Soviet Union's successful 15-year program. More than 40 _^<a!T30539_Soyuz_^>a_ spacecraft visited the stations from 1971 through 1986, when the Salyut station was replaced by the more versatile _^<i__^<a!T22114_Mir_^>a__^>i_ design. The Salyut space stations were used for scientific research, military reconnaissance, and Earth observation._^<g_
With the name of the Russian word for "peace," the Soviet space station _^<i__^<a!T22114_Mir_^>a__^>i_ was launched in February 1986, following the seven _^<a!T28618_Salyut_^>a_ missions. The _^<i_Mir_^>i_ station has more interior space than its predecessors and includes private bedrooms, separate dining facilities, shower, toilet, and exercise apparatus. With numerous docking ports, it was designed to be visited by several teams of cosmonauts and to receive supplies from robot freighters._^<g_See also: _^<a!T30547_space station_^>a_._^<g_
With the _^<a!T1572_Apollo_^>a_ program ending, _^<a!T23154_NASA_^>a_ redirected its energies to new ventures. The first U.S. _^<a!T30547_space station_^>a_, the _^<i__^<a!T30087_Skylab_^>a__^>i_ workshop, was launched in 1973. After three successful missions, in which U.S. astronauts carried out many experiments and broke endurance records, _^<i_Skylab_^>i_ was deemed too impractical to continue until reusable spacecraft could be developed to supply it._^<g_
Resembling a high-tech dune buggy, the _^<a!T20251_Lunar Roving Vehicle_^>a_ (LRV) was introduced with the flight of _^<i_Apollo 15_^>i_. The Lunar Rover wasn't built for speed--its maximum was 8 miles per hour. At less than 500 lbs., though, it was light enough to be folded up during transport. The vehicle carried an impressive array of communications and photographic equipment._^<g_
Without _^<a!T27911_rockets_^>a_, space exploration would be impossible. Enormous progress has been made in rocketry since the space age began. The United States, for example, launched its second satellite from a _^<a!T33737_Vanguard_^>a_ rocket, which had a lift-off thrust of 28,000 lbs. Less than 12 years later, the _^<a!T28877_Saturn_^>a_ V rocket, more than 250 times as powerful, launched _^<i_Apollo 11_^>i_ toward the moon._^<g_
There are three basic types of _^<a!T1382_animation_^>a_. In one technique, two-dimensional (flat) drawings are animated. A second technique involves the animation of three-dimensional objects such as puppets or clay figures. The third technique uses computers to produce and animate images: once the artist has produced an image and stored it in the computer, the machine can be instructed to calculate all the slight adjustments in position that are needed to give the appearance of motion. It can also make all the necessary changes in light, shading, and perspective._^<g_
_^<a!T7757_CD-ROM_^>a_s use _^<a!T19117_lasers_^>a_ to store and retrieve data. A laser encodes binary data as a pattern of microscopic pits on a compact disc. When the disc is placed into a CD-ROM drive, another laser "reads" the pattern of pits and translates it back into the binary 0s and 1s understood by a computer. This information is sent to the computer, which translates the binary 0s and 1s into words, pictures, and sounds. The major advantage of CD-ROMs over traditional magnetic media is the ability to store enormous amounts of data in very little space._^<g_See also: _^<a!T9665_digital technology_^>a_._^<g_
In humans and most other organisms, DNA contains all the information needed to make a _^<a!T6298_cell_^>a_ into a nerve cell, muscle cell, or skin cell--and to determine whether the cell will be a clam cell, fish cell, or human cell. It is the basic substance of heredity, and it makes each living thing unique--a one-of-a-kind organism. DNA found in various organisms is surprisingly similar: it is composed of the same four nucleotides. All the meaning depends on the arrangement of the thousands of nucleotides that make up each DNA molecule._^<g_See: _^<a!T13378_gene_^>a_; _^<a!T13395_genetic code_^>a_; _^<a!T15615_heredity_^>a_._^<g_
In a four-stroke engine, the four distinct functions of combustion are carried out in four continuous movements of the pistons, called strokes. This allows the piston's reciprocating motion (up-and-down or back-and-forth) to be converted to rotary motion, which is necessary to turn the wheels._^<g_See: _^<a!T16995_internal combustion engine_^>a_._^<g_
A two-stroke engine carries out the four functions of combustion via pistons within cylinders, but in only two continuous movements of the pistons. Intake and compression are combined in a single first stroke, while power and exhaust are combined during the second. Because two-stroke engines cannot provide the power and efficiency of four-strokes, they are more appropriate for lightweight uses._^<g_See: _^<a!T16995_internal combustion engine_^>a_._^<g_
The rotary engine--also called the _^<a!T34424_Wankel engine_^>a_--is an advanced type of internal combustion engine which replaces pistons and cylinders with a curved triangular rotor. With 40% fewer parts and one-third the weight of comparable reciprocating engines, the rotary is almost vibration-free, quieter, and capable of running at high speeds for long periods of time._^<g_
With its ability to utilize low-grade fuel and without the need for a carburetor or ignition system, the _^<a!T9639_diesel engine_^>a_ has certain advantages over other types of internal combustion engines: low maintenance costs, greater efficiency, high power output, and fuel economy. However, noise, soot, and pollution generally limit their use to larger, commercial vehicles._^<g_
The gravitational pull between two bodies depends on two factors: the mass of the bodies and the distance between them. For example, the Earth's mass is greater than the Moon's, so its gravitational pull is stronger than that of the Moon. Second, gravitation is strong between bodies close together and weaker between bodies farther apart. If the distance between two bodies doubles, the gravitational pull becomes one-fourth as great as it was originally; if the distance is tripled, the gravitational pull is cut to one-ninth._^<g_See also: _^<a!T10486_Earth, gravitational field of_^>a_._^<g_
Sight begins when _^<a!T19676_light_^>a_ enters the front of the _^<a!T11561_eye_^>a_ by passing through the clear cornea and lens. These structures bend the rays of light to focus an upside-down image on the retina, the lining at the back of the eyeball. The retina contains specialized cells that are sensitive to light. When light strikes these cells, they send a message along the optic nerve that leads from the eye to vision centers in the brain. In the brain the messages are interpreted, and then we see._^<g__^<a!T24425_optics_^>a_._^<g_
_^<a!T30467_Sound_^>a_ waves traveling through the air are funneled into the _^<a!T10471_ear_^>a_ canal and bump against the eardrum, making it vibrate. The vibrations set the three tiny ear bones jiggling in the middle ear. These jiggling bones amplify the sound waves and make the oval window vibrate, too. Pressure waves are set up in the inner-ear fluid and race up and down the coils of the cochlea. These waves push against a membrane, causing hair cells to bend back and forth. Their movement is picked up by tiny nerve fibers attached to the hair cells. The cochlear nerve carries messages from the ear to the brain, which interprets the messages._^<g_
Air inhaled into the alveoli is rich in oxygen. Meanwhile, waste-carrying blood is pumped from the heart through the pulmonary arteries (blue) and into the capillaries that surround the alveoli. A quick exchange takes place. The waste gas carbon dioxide, plus some waste water, move out of the blood into the air sacs and are breathed out of the body. Oxygen is picked up by the red blood cells and carried back to the heart via the pulmonary veins (red). From the heart, the oxygen-rich blood is pumped throughout the body._^<g_See also: _^<a!T20262_lungs_^>a_._^<g_
All the rays that make up a beam of _^<a!T19117_laser_^>a_ light are of exactly the same wavelength. This makes it possible for all the waves to travel in phase (in step). That is, the crests of all the waves are lined up. When _^<a!T19676_light_^>a_ waves are in phase, they strengthen one another. The waves all move together in the same direction, without spreading. This means they can be focused by a lens or curved mirror as an intense, powerful beam on a very small spot. They also can be sent long distances with little weakening._^<g_See also: _^<a!T7545_coherent light_^>a_._^<g_
When a _^<a!T6298_cell_^>a_ reproduces, it divides into two cells. The original cell is called the parent cell. The new cells that are formed are called daughter cells. Each daughter cell contains all the replicated cell parts of the parent cell, including DNA, the material that makes up the _^<a!T13378_genes_^>a_ in chromosomes and determines heredity. Whether division is by _^<a!T21543_meiosis_^>a_ or _^<a!T22190_mitosis_^>a_, it is a continuous process, though it has certain recognizable stages._^<g_
During _^<a!T21757_metamorphosis_^>a_ more than just the shape of the animal changes. Many parts inside the animal's body change. So does its way of life. There are several reasons why metamorphosis occurs. First, it eliminates competition among members of the same species. Second, it improves the geographical distribution of the species. And third, particularly in certain _^<a!T16937_insects_^>a_, it enables the storing of food reserves to be used by the adults._^<g_See also:_^<a!T9506_development_^>a_._^<g_
So far, scientists have not been able to harness _^<a!T13003_nuclear fusion_^>a_ in a way that will make it useful for peaceful purposes, such as the production of power. Fusion has the potential to provide vast amounts of electrical energy because there is a cheap, almost unlimited supply: the waters of the ocean. A spoonful of _^<a!T9498_deuterium_^>a_, obtained from 3-4 liters (0.8-1.1 gal) of water, contains as much energy as 1,200 liters (317 gal) of gasoline._^<g_
The name _^<a!T25733__^<i_photosynthesis_^>i__^>a_ comes from two Greek words meaning "putting together in light." The process is made possible by _^<a!T6950_chlorophyll_^>a_, a green chemical found in plant leaves. Chlorophyll acts as a catalyst, enabling a chemical change--i.e., photosynthesis--to take place while remaining basically unchanged itself. It helps make plant leaves the world's most important factories. Animals and practically all other organisms, who cannot make their own food, depend on green plants for food, either directly or indirectly, as well as for oxygen._^<g_
On the morning of June 6, 1944, Gen. Dwight D. _^<a!T10726_Eisenhower_^>a_ faced a major decision. Five thousand ships and craft were ready to cross the English Channel, but stormy seas had already pushed back the invasion one day. Further delay would have meant waiting another two weeks until tidal conditions improved. Eisenhower decided to give the go-ahead, and the rest is history. By nightfall of June 6, 1944, the Allies had a foothold on the European continent._^<g_See also: _^<a!T23823_Normandy Invasion_^>a_; _^<a!T31175_strategy and tactics, military_^>a_; and _^<a!T35397_World War II_^>a_._^<g_
John F. _^<a!T18212_Kennedy_^>a_ won the presidential election of 1960 by only a razor-thin margin, but his inaugural speech helped garner the support of much of the American public. His honeymoon was brief; less than three months later the _^<a!T3021_Bay of Pigs invasion_^>a_ failed and Kennedy became deeply mired in the resulting debacle. Over the next few years Congress continued to drag its heels on implementing the president's proposals. On November 22, 1963, President Kennedy was killed, leaving the vision for America he described so eloquently in his inaugural speech unfulfilled._^<g_See also: _^<a!T8612_Cuban Missile Crisis_^>a_._^<g_
The rocket-powered X-15 actually flew to speeds in excess of 4,500 mph and reached altitudes of up to 354,000 feet before the program ended in 1968 after 199 flights. A number of the pilots who flew X-15s were awarded astronaut wings for flying research missions at the edge of space._^<g_See also: _^<a!T35494_X-series aircraft_^>a_._^<g_
When the Soviets launched _^<i__^<a!T30766_Sputnik_^>a_ 1_^>i_ in 1957, people all over the world considered it a miracle of the modern age. This tiny aluminum sphere--only 23 inches in diameter and weighing 184 pounds--not only had great technological significance, it also had great political significance. Some said that Soviet Premier Nikita Khrushchev used the Soviet missions to build prestige at the risk of flight safety. While stories of unreported accidents and deaths have never been proved, records brought to light in 1996 revealed that there had been a near-disaster on board Yuri _^<a!T13051_Gagarin_^>a_'s _^<i__^<a!T34231_Vostok_^>a_ 1_^>i_ space flight in 1961._^<g_See also:_^<i__^<a!T22114_Mir_^>a__^>i_; _^<a!T30541_space exploration_^>a_; _^<a!T32117_ Tereshkova, Valentina_^>a_._^<g_
In his autobiography, Buzz _^<a!T726_Aldrin_^>a_ described the pressures of returning to public life after his moon journey, and his subsequent nervous breakdown and recovery. Neil A. _^<a!T1839_Armstrong_^>a_ went on to serve as vice-chairman of a presidential commission appointed to investigate the destruction of the Space Shuttle _^<i_Challenger_^>i_ in 1986, and Michael _^<a!T7611_Collins_^>a_ became the director of the National Air and Space Museum of the Smithsonian Institution._^<g_See also:_^<i__^<a!T22114_Mir_^>a__^>i_; _^<a!T30541_space exploration_^>a_; _^<a!T32117_ Tereshkova, Valentina_^>a_._^<g_
The Hubble _^<a!T30549_Space Telescope_^>a_ has enabled astronomers to see the first clear evidence of a brown dwarf star, the birth and death of stars, and the discovery of oxygen on Jupiter's moon, Europa. It has opened the doorway to a systematic search for black holes, the gravitational "sinkholes" that trap everything, even light. Some photos, like those from spiral galaxy M100, can even yield clues to the size and age of the universe. It is appropriate that the telescope was named for Edwin Powell _^<a!T16310_Hubble_^>a_ (1889-1952), the man who provided evidence for the expansion of the universe and who demonstrated the existence of galaxies outside the Milky Way._^<g_See also: _^<a!T2082_astronomy and astrophysics_^>a_; _^<a!T30546_Space Shuttle_^>a_._^<g_
The U.S. _^<a!T30546_Space Shuttle_^>a_ consists of an orbiter, an external tank, and solid rocket boosters. The orbiter functions as a rocket stage during launch; when the craft is in orbit it functions as a spaceship. On reentry and landing, the orbiter becomes a glider. The second part of the shuttle is the external tank, which contains liquefied propellants for the engines. The shuttle also contains two solid rocket boosters, each of which produces up to 2.65 million pounds of thrust for takeoff._^<g_See also: _^<a!T373_aerospace industry_^>a_; _^<a!T2077_astronaut_^>a_; _^<a!T30545_space programs, national_^>a_._^<g_
In mid-1942 the United States assigned a project to the U.S. Army Corps of Engineers; its code name was _^<a!T20899_Manhattan Project_^>a_, and its goal was the creation of the first _^<a!T2143_atomic bomb_^>a_. The bomb was designed at a laboratory located in Los Alamos, New Mexico, under the direction of J. Robert _^<a!T24417_Oppenheimer_^>a_. The first atomic bomb using plutonium was tested on July 16, 1945, at a site called Trinity, near Alamagordo, New Mexico. At the time, President Harry S. Truman was at a conference in Potsdam, where the Allied nations met after the defeat of Germany. The Potsdam conference ended on August 2, 1945, and the atomic bomb was dropped on _^<a!T15842_Hiroshima_^>a_ just four days later._^<g_See also: _^<a!T23031_Nagasaki_^>a_._^<g_
Within a year after the _^<a!T21005_March on Washington_^>a_, Congress passed the Civil Rights Act of 1964, which prohibited discrimination in employment, as well as creating the Equal Employment Opportunity Commission. In the same year, Dr. Martin Luther _^<a!T18389_King_^>a_ became the youngest recipient of the Nobel Peace Prize. In 1965, President Lyndon Johnson pushed the Voting Rights Act through Congress, resulting in massive voter registration by blacks in the south._^<g_See also: _^<a!T402_African Americans_^>a_; _^<a!T7205_civil rights_^>a_; _^<a!T30509_Southern Christian Leadership Conference_^>a_._^<g_
Eleanor _^<a!T28031_Roosevelt_^>a_ (1884-1962) was the wife of one president, Franklin D. _^<a!T28032_Roosevelt_^>a_, and the niece of another, Theodore Roosevelt. Her role as wife and mother kept her from becoming directly involved in the world of politics until she became First Lady, and then she broke the mold: she lectured, broadcast a radio program, wrote a newspaper column, and traveled widely. She became the eyes and ears for her husband, and she used her high profile to fight for a multiplicity of interests. After her husband died in 1945, Eleanor Roosevelt went on to participate in 17 more years of public service._^<g_See also: _^<a!T16376_human rights_^>a_; _^<a!T33451_United Nations_^>a_._^<g_
After _^<a!T35397_World War II_^>a_, _^<a!T3463_Berlin_^>a_ was divided into four sectors, under the control of the United States, France, Great Britain, and the USSR. The Soviet sector became the capital of the German Democratic Republic, or East Germany, and the western sectors became an unofficial part of the Federal Republic of Germany, or West Germany. After reunification, Berlin became the official capital of _^<a!T13521_Germany_^>a_ once again, as it had been before the war._^<g_East Berlin and the GDR lagged far behind the West in economic development during the years that the city was divided, and that situation has continued. The reunited nation has faced giant problems, including massive unemployment and lack of technical infrastructure. The German government has been supplying funds to attempt to move the former GDR from a planned economy to a market system._^<g_See also: _^<a!T3470_Berlin Wall_^>a_; _^<a!T7568_cold war_^>a_; _^<a!T17143_Iron Curtain_^>a_._^<g_
The team that discovered the_^<i_ _^<a!T32573_Titanic_^>a__^>i_ was part of a joint U.S.-French expedition, headed by Robert Ballard of the _^<a!T35338_Woods Hole Oceanographic Institution_^>a_ in Massachusetts and Jean-Louis Michel of the Institute for Research and Exploration of the Sea in Paris. Ballard's _^<i_Argo_^>i_ photographed the sunken vessel two-and-a-half miles under the ocean surface, 400 miles southeast of Newfoundland. Since their discovery in 1985, the site of the_^<i_Titanic_^>i_ has been a target for scientists and treasure hunters. And in 1994, 150 articles retrieved from the ship were exhibited at the National Maritime Museum in Greenwich, England, including silver trays, a steward's jacket, and two of the_^<i_Titanic_^>i_'s portholes. While _^<i_Titanic_^>i_ buffs lined up to see the booty, many survivors opposed further plans to disturb the ship._^<g_See also: _^<a!T33405_underwater archaeology_^>a_._^<g_
In _^<i__^<a!T29875_Silent Spring_^>a__^>i_, published in 1962, Rachel _^<a!T6009_Carson_^>a_ (1907-1964) wrote that 40 species of birds were likely to become extinct, largely because of the indiscriminate use of pesticides. According to Carson, not only would the poisons in chemical pesticides kill birds and other creatures directly, but they would also create a rift in their food chain by killing insects that birds eat. But since _^<i_Silent Spring_^>i_ was written, the Environmental Protection Agency was established, the Endangered Species Act passed, and numerous conservation laws have gone into effect. Largely because of Carson's dire warnings, her predictions did not come true._^<g_See also: _^<a!T11095_environmental movements_^>a_; _^<a!T9125_DDT_^>a_; _^<a!T25523_pesticides and pest control_^>a_._^<g_
Clicking the "Background" button on any of the main Guided Tour screens will provide hyperlink access to introductory or related articles in the encyclopedia. The main screen for each Guided Tour always appears first in the media list (in the panel at the left of your screen) for that subject._^<g_
For a general introduction to this subject, see the articles _^<a!T1094_American literature_^>a_ and _^<a!T23932_novel_^>a_._^<g_
For background reading on the subject of women in modern American society, see the articles _^<a!T11837_feminism_^>a_ and _^<a!T35298_women's rights movements_^>a_._^<g_
A broad overview of this exciting subject can be found in the article _^<a!T11533_exploration_^>a_._^<g_
The article _^<a!T7568_cold war_^>a_--and others you may find on your own--provide a context for your multimedia tour of the 1950s._^<g_
Before taking this Guided Tour, take a few minutes to read the survey articles on _^<a!T12382_food_^>a_, the _^<a!T12387_food industry_^>a_, and human _^<a!T24018_nutrition_^>a_._^<g_
Recommended introductory articles include the following: _^<n__^<a!T16824_Indians, American_^>a_; _^<n__^<a!T16826_Indians of North America, art of the_^>a_; _^<n__^<a!T16827_Indians of North America, music and dance of the_^>a_._^<n__^<g_
Editor of "Asia Pacific Report" for _^<i_Chemical Marketing Reports_^>i_._^<g_
The overview article _^<a!T16937_insect_^>a_ provides a good starting point for this Guided Tour._^<g_
For background reading on this interesting subject, see the survey articles _^<a!T21467_measurement_^>a_ and _^<a!T16956_instrumentation_^>a_._^<g_
Before taking this Tour, you might enjoy reading the articles on _^<a!T13593_giants_^>a_, _^<a!T23002_mythology_^>a_, and _^<a!T31436_supernatural literature_^>a_._^<g_
The article _^<a!T22800_multimedia_^>a_ will provide a brief introduction to this subject._^<g_
The articles _^<a!T22918_music_^>a_ and _^<a!T30467_sound and acoustics_^>a_ provide perfect starting points for this fascinating Tour._^<g_
For a general definition and introduction, see the encyclopedia article on _^<a!T28001_romanticism_^>a_._^<g_
For in-depth background on this subject, see the articles _^<a!T28284_Russia_^>a_ and _^<a!T33435_Union of Soviet Socialist Republics_^>a_._^<g_
Before embarking on this Tour, take the time to read the general articles on _^<a!T29561_Shakespeare, William_^>a_ and the _^<a!T10892_Elizabethan Age_^>a_._^<g_
Before you explore this area, we encourage you to read the following articles: _^<a!T34625_weapons_^>a_ and _^<a!T31175_strategy and tactics, military_^>a_._^<g_
The following articles are recommended as background reading:_^<a!T17192_Islam_^>a_, _^<a!T17196_Islamic art and architecture_^>a_, and _^<a!T17199_Islamic society_^>a_._^<g_
Freelance Writer._^<g_
Department of Art History, Northwestern University, Evanston, Ill._^<g_
School of Journalism and Mass Communication, University of Minnesota, Minneapolis._^<g_
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Professor of English, Queens College, Flushing, N.Y._^<g_
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Associate Professor and Director, Emergency Technology Program, University of Texas Health Science Center, San Antonio._^<g_
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Instructor, Department of City and Regional Planning, University of Pennsylvania, Philadelphia._^<g_
Former Professor of Vocal Interpretation, Guildhall School of Music and Drama, London._^<g_
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The National Heart, Lung, and Blood Institute, U.S. Department of Health and Human Services._^<g_
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Cook College, Rutgers University, New Brunswick, N.J._^<g_
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Vernon F. Taylor Distinguished Professor of Economics, Trinity University, San Antonio, Tex._^<g_
Professor of History, Arizona State University, Tempe._^<g_
Faculty Fellow, Lamont-Doherty Earth Observatory, Department of Geological Sciences, Columbia University, New York City._^<g_
Post-doctoral Researcher, Yale University, New Haven, Conn._^<g_
Assistant Professor of History, University of Memphis, Memphis, Tenn._^<g_
Professor of Environmental and Plant Biology, Ohio University, Athens._^<g_
With the launch of the first _^<a!T30546_Space Shuttle_^>a_ in 1981, a new era in manned space flight began, an era that paved the way for ambitious scientific, commercial, and military applications. The concept behind the shuttle was the reusable spacecraft, one that could act as a rocket at launch, a spaceship during orbit, and a hypersonic glider upon reentry._^<g_
Department of History, Siena College, Loudonville, N.Y._^<g_
Staff Writer._^<g_
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U.S. Department of Transportation, National Highway Traffic Safety Administration, Washington, D. C._^<g_
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Professor of Sociology, Adelphi University, Garden City, N. Y._^<g_
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Visiting Professor, California Institute of Asian Studies, San Francisco._^<g_
Freelance Writer._^<g_
Department of Sociology, University of California, Berkeley._^<g_
Associate Professor of Music, Princeton University, Princeton, N.J._^<g_
Freelance Writer._^<g_
History Department, Purdue University, West Lafayette, Ind._^<g_
Director of Education and General Curator, Zoological Society of San Diego, San Diego, Calif._^<g_
Freelance Writer._^<g_
Freelance Writer._^<g_
Research Scientist, NASA, Goddard Institute for Space Studies; Lamont Doherty Earth Observatory, Palisades, N.Y._^<g_
Elbert Covell College, University of the Pacific, Stockton, Calif._^<g_
Staff Writer._^<g_
United States Military Academy, West Point, N.Y._^<g_
Freelance Writer._^<g_
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Department of Anthropology, Columbia University, New York City._^<g_
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Architectural Historian._^<g_
Professor of Slavic Literatures, Columbia University, New York City._^<g_
The myofibrils that make up _^<a!T22901_muscle_^>a_ fibers are divided into short segments called sarcomeres. Sarcomeres, in turn, consist of thick and thin filaments that overlap along part of their length. A muscle contracts when the thin filaments of its sarcomeres slide between the thick filaments, shortening the length of the sarcomeres. This activity requires abundant energy, which comes from the breakdown of phosphorus compounds present in muscle tissue._^<g_See: _^<a!T22902_muscle contraction_^>a_._^<g_
Editor in Chief, _^<i_Organic Gardening_^>i_ Magazine._^<g_
Editor and Writer._^<g_
The _^<a!T19858_liver_^>a_, located on the right side of the body directly underneath the diaphragm, is the largest organ in the body. It weighs about 1.4 kg (3.1 lbs.) and consists of four lobes: the large right and left lobes and, attached to the right lobe, the smaller quadrate and caudate lobes. In addition to taking to part in digestion by producing bile, the liver stores carbohydrates as _^<a!T13836_glycogen_^>a_, metabolizes fats and proteins, filters impurities from the blood, produces blood-clotting factors, and destroys worn-out red blood cells._^<g_
_^<a!T16141_Hormones_^>a_ regulate many body functions, helping to maintain the stability of the body's internal environment and playing a critical role in growth and development. These chemicals act through receptors. Each hormone fits into a receptor in a lock-and-key fashion. The hormone (the key) will only communicate with cells that have the right kind of receptor (the lock). This is how they manage to travel throughout the body and communicate with certain types of cells._^<g_
Crocodiles have a transparent third eyelid, the nictitating membrane, which allows them to see underwater._^<g_
A crocodile's skin consists of leatherlike bony plates and scales called scutes._^<g_
The dorsal scales of most crocodiles are dull brown, green, and black. This allows them to blend in with the muddy water in which they live so they can surprise their prey._^<g_
There are many types of crocodilians, inhabiting four of the six continents. But only the Nile, or African, crocodile has come close to invading an entire continent. It lives, or has lived, in every part of Africa that has enough water to support a large amphibious reptile. Some people fear that it is a major threat to human life in those regions._^<g_
All crocodilians have a four-chambered heart. Unlike humans, who have only one aorta, crocodiles have two aortic arches which carry blood from the heart through the body._^<g_
The cloaca (from the Latin word for sewer) is the chamber from which all waste products leave the crocodile's body._^<g_
Crocodiles have large, solid skulls. Common with the dinosaurs that proceeded them, crocodilians have diapsid skulls (two temporal openings on the side)._^<g_
A large crocodile may replace each of its teeth more than 40 times during its life._^<g_
Special muscles close to the nostrils help seal off the windpipe and gullet so the crocodile can stay submerged._^<g_
A crocodile's eye is set for distance vision; muscular action is required to look at closer objects._^<g_
Crocodiles propel themselves through water by undulating their muscular tails. They can swim effectively upstream using their tails and hind limbs._^<g_
In order to find prey, dogs have developed an amazing sense of smell. They have 220 million olfactory cells in their nose, compared with about 5 million in a human's nose._^<g_
Dogs can hear tones of up to 35 kHz, compared to 20 kHz for humans. Dogs with pointed, upright ears can hear better than floppy-eared dogs._^<g_
A dog's eyesight is sharp in dim light because of the tapetum licidum, a light-reflecting layer at the back of its eyes. Because of this, dogs' eyes shine in the dark, as do the eyes of cats._^<g_
Dewclaws, which only appear on a dog's front paws, are the remnants of the first toes of the dog's ancestors; they no longer touch the ground when a dog walks or runs._^<g_
This predecessor to the Doberman comes in two sizes: standard, pictured here, and toy. The smaller toy breed is more high-strung, and neither is very friendly with strangers. Aloofness makes it an alert watchdog, but the Manchester tends to fatten significantly with age, limiting its mobility._^<g_
The dog's esophagus pushes food from the mouth to the stomach by means of muscular contractions called peristaltic waves._^<g_
At the intersection of the dog's large and small intestines is the cecum, which is similar to a human's appendix. Some dogs have gastrointestinal problems caused by whipworms in the cecum._^<g_
The liver is the largest organ in a dog's body. It has six lobes, five more than a human's liver._^<g_
The bones of a dog's skull protect its brain, mouth, eyes, nose, and ears._^<g_
As in all animals, the dog's vertebrae protect the heart, lungs, and digestive system._^<g_
The sternum, or breastbone, is made of soft bones and cartilage, so it moves as the dog breathes. The last pair of ribs is not connected to the sternum._^<g_
Dogs can bite and chew food because of the large muscles in their face. The temporalis provides the downward motion and strength of the jaw, the masseter enables side-to-side jaw motion._^<g_
Dogs can bite and chew food because of the large muscles in their face. The temporalis provides the downward motion and strength of the jaw, the masseter enables side-to-side jaw motion._^<g_
The pectoralis minor is the muscle that connects the ventral walls of the chest with the bones of the dog's arm and shoulder._^<g_
Dogs can bite and chew food because of the large muscles in their face. The temporalis provides the downward motion and strength of the jaw, the masseter enables side-to-side jaw motion._^<g_
The male lion's mane may signal his status to potential mates or enemies and may protect his neck during battles with other males. If the lion's mane is black, it intimidates other males from a distance._^<g_
Adult lions are usually light brown to dark ochre in color, with no spots, but cubs may have spots on the legs and belly until they are grown._^<g_
Lions are rumored to develop a preference for human meat once they've sampled it. Perhaps because of this belief, or because they will prey on livestock, lions have been hunted by man to near-extinction. Once covering much of Europe, Asia, and Africa, their domain has shrunk to a few reserves in Africa and one in India._^<g_
The lion has a fairly simple digestive system, since it is a carnivore and doesn't need the more complex digestion of herbivores._^<g_
Since there are few sweat glands on a lion's skin, it must pant to cool its body._^<g_
The lion's rear upper premolars, called carnassials, shear past each other when the jaw is closed. These function as blades when killing prey or tearing chunks of meat from a carcass._^<g_
The lion's skull has large openings for the eyes, which may indicate a greater reliance on visual information for hunting and capturing prey._^<g_
The bones that support the lion's larynx and the base of its tongue remain partly soft (cartilaginous), which may affect the lion's roar. The chilling sound, usually heard after sundown or after killing or eating, can be heard for miles._^<g_
As do most cats, a lion uses its muscles to retract its claws. When the claws are retracted, the dorsal and ventral muscles are relaxed. When these muscles contract, the spring ligament stretches to push the claws from the sheath._^<g_
The masseter and medial pterygoid muscles control side-to-side movement of the jaw. Meat eaters, like lions, don't use this side-to-side jaw movement as much as do plant eaters._^<g_
The snake's transparent lower eyelid is attached to the unused upper eyelid, which prevents the snake from blinking and gives it its hypnotic stare._^<g_
Located in the snake's mouth, Jacobson's organs are the chemical receptors that can detect tiny chemical particles given off in the body scent of animals. With this apparatus, snakes are better able to track prey than are bloodhounds._^<g_
The cobra is the only snake that assumes the erect "candlestick" posture before striking. Its venom is neurotoxic, meaning it interferes with nerve impulses that control breathing and heartbeat._^<g_
Snakes have flexible stomachs, suited to digesting large chunks of animals. Snakes use enzymes during digestion to break down the hair, feathers, bones, and other body parts of their prey._^<g_
Most snakes have only one working lung, the right lung, which extends through most of the snake's body and ends in a thin sac that stores air._^<g_
Muscles around the venom-producing salivary glands pump venom through the fangs and into prey._^<g_
The jaws of a snake can open wide so it can "walk" its jaws over the prey._^<g_
The most common way for snakes to move is called lateral undulation, the process of contracting and relaxing a set of muscles down each side of the body._^<g_
The snake's skull has great elasticity, enabling it to swallow large animals. In many snakes, the only solid portion of the skull is the braincase._^<g_
All four of the fang-bearing bones in a snake's mouth are loosely attached to the skull by ligaments and are movable, the better to trap prey._^<g_
Snakes don't have external ears, but they do have a small columella bone between the inner ear and the jaw hinge which picks up vibrations through the ground._^<g_
Not all grasshoppers have wings, but the ones that do usually have two pairs. The front wings, called tegmina, act as covers for the hind wings, which are membranous._^<g_
Male grasshoppers make music (stridulation) by rubbing their hind legs against their front wings._^<g_
Some grasshoppers have oval eardrums, called tympana, which are located on their abdomens._^<g_
Grasshoppers have two compound eyes, which are made up of thousands of small eyes. Grasshoppers also have three simple eyes, which can perceive changes in light._^<g_
There are 5,000 known species of grasshopper, of which only 100 are found in North America. They are voracious eaters of crops, and their conquest of large swaths of farmland is the stuff of legend in the American heartland._^<g_
The grasshopper's respiratory system is made of spiracles, or breathing pores, and tracheae, a network of tubes carrying oxygen through the body._^<g_
Because grasshoppers are cold-blooded insects, their pulse rates change according to the temperature of their environment._^<g_
The nervous sytem of the grasshopper includes the brain, ganglia, and nerve cords._^<g_
The nervous sytem of the grasshopper includes the brain, ganglia, and nerve cords._^<g_
The nervous sytem of the grasshopper includes the brain, ganglia, and nerve cords._^<g_
Food passes into the grasshopper's esophagus, crop, and stomach._^<g_
The last few sections of the grasshopper's 11-part abdomen are connected with parts of its reproductive organs._^<g_
All fish have mucous-coated skin. The mucous helps protect the fish from parasites, fungi, and bacteria, as well as helping the fish navigate smoothly through the water._^<g_
Dorsal (back) and anal (underneath) fins serve like the keel of a boat. Paired fins are found on both sides of the body. The front pair, called pectoral (shoulder) fins, and the back pair, pelvic (leg) fins, support balance and movement._^<g_
Fish don't need eyelids to protect their eyes from glare and retain moisture, since there is little light under the sea and no lack of moisture._^<g_
The carnivorous golden, or yellow, perch is native to the ponds, lakes, and slow-moving streams of northeastern North America. It reaches an average size of 1 lb (.45 kg) feeding mostly on smaller fish._^<g_
Most fish have teeth to grind food, but the food is further broken down within the muscled part of the stomach, the gizzard, which grinds it into pulp._^<g_
Blood is pumped directly to the gills from a two-chambered heart._^<g_
A fish's brain is divided into three sections: the forebrain, which controls the sense of smell; the midbrain, which deals with sight; and the hindbrain, which controls balance and respiration._^<g_
Most bony fish have a swim bladder, a hydrostatic organ that when filled with gas enables a fish to achieve equal buoancy with water and allows it to move with little energy. Many bottom-dwelling fish have no swim bladder._^<g_
The backbone of a fish is formed by a column of disk-shaped bones called vertebrae. From the vertebrae, the ribs extend toward the belly._^<g_
The skull of a fish consists of a cranium and bony gill supports._^<g_
In most bony fishes, the upper jaw is not fused to the skull; this gives the jaws some mobility for feeding._^<g_
Fetlocks are tufts of hair on the rear surface of the horse's hoof. The fetlocks of draft horses are called feathers. The fetlock joints are supported by elastic ligaments which help power the horse's movement._^<g_
Only the whale and the ostrich have larger eyes than the horse._^<g_
Averaging 15.2 hands (each hand being 4 inches, and the .2 representing two inches) and 1,100 lbs., the American saddle horse is classified as a light horse. The other two major American horse classes are draft horses and ponies. These classes are determined largely on the basis of weight and height._^<g_
A resting horse breathes about 8 to 16 times per minute. Its great lung capacity makes it a superb racer._^<g_
The age of a horse can be determined from its teeth; experts look at how much the teeth are worn down by grazing. At 29 years of age, a horse's teeth are worn down to the roots._^<g_
The white-crowned sparrow prefers the openness of the western United States and northeastern Canada. Its citified cousin, the house sparrow, likes the company of humans. Introduced to Brooklyn in the 1850s to combat a blight of cankerworms, the house sparrow is now a common sight in cities across the continent._^<g_
The number of vertebrae on birds range from 39 to 63, depending on the length of the neck; the back vertebrae of flying birds are fused._^<g_
The breastbone, or sternum, protects the bird's internal organs and supports the muscles that enable the bird to fly._^<g_
While powerful muscles arise from the keeled bony sternum in flying birds, most flightless birds have reduced flight muscles and have lost the keel on the sternum._^<g_
Air enters a bird's body through the nostrils, trachea, air sacs, and lungs. After the air leaves the lungs, oxygen passes through the bloodstream to the body cells. Almost all air is replaced with each breath._^<g_
A bird's heart beats two to four times faster than a human's, on average. While the non-flying ostrich's heart beats only about 60 or 70 times per minute, the hummingbird's heart can beat over 1,000 times per minute._^<g_
A bird's gizzard has strong muscular walls that grind the foods which, in most animals, teeth would grind. Also aiding in breaking down the unchewed food are strong digestive juices and the friction of small stones and pebbles that birds often swallow._^<g_
Birds have excellent eyesight, aided by neck mobility of up to 270 degrees. The vision of predators is especially acute; hawks can see up to eight times more sharply than humans._^<g_
Cats have sweat glands in the pads of their feet (eccrine glands) and on other parts of their bodies (apocrine glands)._^<g_
Like other crepuscular animals, the cat has a layer of reflecting tissue behind the cells of its retina, enabling light to pass through the retina two times. This allows cats to see well in twilight._^<g_
The sandpapery, dry cat tongue is covered with sharp projections called papillae, which enable the cat to both remove flesh from its prey and clean its fur efficiently._^<g_
The tail of the cat is flexible enough to help in balancing, but it is ultimately unecessary. Some breeds, like the Manx, don't have tails._^<g_
The domestic shorthair, less luxurious than a longhaired cat and without the telltale markings of other shorthairs like the Siamese and the Abyssinian, is often erroneously regarded as an alley cat. In fact, show cats of this breed have been reared with care for generations._^<g_
One main difference between domestic and wildcats is that domestic cats have smaller intestines. Since they don't get as much protein as predatory cats, their intestines must maximize the absorption of amino acids._^<g_
In a study of the stomach contents of city stray cats, only three percent of their diet was meat (rodents); the rest was garbage._^<g_
A cat has between 28 and 30 teeth. The canine teeth stab and hold prey, and the carnassial teeth cut food._^<g_
The lower jaw of the cat is attached to the skull. This permits only up-and-down movement when it chews._^<g_
A 5-cm (2 in) frog of South Africa, _^<i_Ptychadena oxyrhyncha_^>i_, can jump nearly three times its body length. The front limbs of the jumping frog are used as shock absorbers._^<g_
Some frogs have highly developed tongues, which they can extend to capture prey. The end of the tongue has glands that secrete a viscous material that holds the prey until it is eaten._^<g_
The marsh frog, a member of the terrestrial frog family, is among the most common of frog types. Members of this family can be found in wet habitats as far north as Sweden and as far south as South Africa._^<g_
Frogs and toads lack a neck, so they only have 6 to 10 vertebrae. Humans, by comparison, have 26._^<g_
Frogs don't really need teeth, since they swallow their prey whole, but some frogs do have teeth so small that they can only be seen through a microscope._^<g_
Frogs swallow their food whole, after which it passes down the esophagus to the stomach. After the food passes the small intestine, it is digested and carried by water through the intestinal wall to the blood._^<g_
As the tadpole begins its metamorphosis into a frog, its gills disappear and its lungs develop. Other biochemical changes take place, including the shortening of the intestines._^<g_
The flying frog of Borneo can soar through the air, using its webbed feet as parachutes. For climbing, many frogs have suckerlike adhesive disks on their fingers and toes._^<g_
The frog's upper eyelids are fixed, and the lower eyelids consist of two movable transparent membranes (nictitating membranes) which clear away particles that disturb vision._^<g_
Frogs have eardrums that look like drumheads; these lie flush to the side of the head and are extremely sensitive to vibration._^<g_
Like other members of the river, or "dabbling," duck classification, such as the mallard, pintails feed on aquatic foliage by dipping just their bills or heads into the water. Their young survive mostly on a diet of crustaceans and insects until their systems are ready for the more difficult to digest vegetation._^<g_
Eiders, members of the sea duck family, are skilled divers that nest on freshwater bodies. They pursue bottom-dwelling mollusks and some fish._^<g_
With a range spanning most of North America, the Canada goose's environment has been encroached upon by humans and their industries. The geese have adapted well, breeding in larger numbers along streams, lakes and ponds closer to urban centers, making them a common sight outside the tundra._^<g_
The Alaskan brown bear, at the top of the tundra food chain, is the largest known living carnivore. Though an omnivore, the brown bear feeds mostly on fish. Adult males will reach 9 ft (2.8 m) in length and 1,700 lbs. (780 kg) in weight._^<g_
Moose are not herd animals, but are independent, singularly searching for shrubs, trees and water vegetation on which to feed. They will often entirely submerge their 1,800 lb (825 kg) frame into water to get at plants on lake bottoms._^<g_
The forget-me-not's hardiness and preference for moist areas make it a common perennial in this environment. It grows to about 18 inches and sports flowers that are bright blue with yellow, pink or white centers._^<g_
Fireweed, so-called because it is commonly among the first plants to grow in an area that has been burned, emerges quickly and heartily during the short tundra summer. It is considered the floral emblem of the Yukon._^<g_
This mighty rodent eats nearly its own weight each day in seeds, bark, roots and leaves and is sexually mature enough to breed at the age of five weeks. Their large litters and rapid reproduction ability, coupled with few defense mechanisms help make them a mainstay in the diet of tundra perdators._^<g_
Cotton grass is a sedge, which differ from grass in that their stems (culms) are solid where as grass culms are generally made up of solid joints and hollow internodes. The roots of cotton grass provide at least a little resistance to the severe land erosion that can occur in the tundra._^<g_
Also known as the bristle-thighed curlew, this bird breeds in Alaska during the tundra summer then flies 6,000 miles over water to winter in the South Pacific._^<g_
In the summer, the mouse-like collared lemming develops gray cheeks, tawny ear spots, chestnut shoulders and chest and a black stripe down its back. In the winter they turn grayish white._^<g_
Tundra lemmings emerge from furrows to feast on the tender shoots of cotton grass. They also create short tunnels leading to grass-lined chambers under the tundra where food is plentiful but security not absolute._^<g_
The carnivorous least weasel is an efficient hunter and killer. It can quickly maneuver its flexible body to squeeze through any hole large enough for its head and then kill its prey in seconds. It will often kill more than it needs and store the excess for later consumption._^<g_
As opposed to many other squirrel genera, the Arctic ground squirrel is solitary rather than communal and hibernates alone in an insulated burrow._^<g_
Permafrost refers to ground that does not completely thaw during a region's warm season. Permafrost covers about 50% of the land area of Russia and Canada, 20% of China and 82% of Alaska. It's thickness reaches a depth of 2,300 feet (700 m) in parts of northern Alaska and thins progressively to the south to 3 - 10 feet (1 - 3 m)._^<g_
Periwinkle snails live in clusters on rocks in the upper intertidal zone, grazing on microscopic algae that cover the rocks. To protect against drying out during low tide, they withdraw the head and foot into the shell, closing the opening with a horny plate on the foot. _^<g_
Pressure from the solar wind - a stream of electrified particles and radiation continually emitted from the Sun - pushes the dust particles and gases outward and away from the comet's head, forming a long tail. The breadth of the tail increases as the distance from the head increases._^<g_
Like all petrels, pintado petrels usually come ashore only for nesting. They make their nests on seaside cliffs on Antarctic islands. Excellent divers, these birds feed on fish, squid, crustaceans, and ships' garbage._^<g_
A wandering albatross may fly for months over the ocean, alighting on the water's surface only to feed. It eats fish, squid, and crustaceans, usually on the surface but occasionally by plunging._^<g_
Pink-footed shearwaters are excellent flyers and highly migratory, summering in the Antarctic and wintering off the Pacific Coast of North America. When hunting, they glide close above the water's surface, picking up small crustaceans and fish such as pilchards. _^<g_
Although they have earned their name as predators of seals, sea lions, walruses, dolphins, and other whales, killer whales are not wanton and feed primarily on fish and squid. They hunt in packs, called pods, of 2 to 40 that travel together for a lifetime._^<g_
Cormorants are strong fliers with long necks and stout bodies. They are voracious fish eaters, diving from the water's surface to pursue prey--a dangerous habit, for they can be caught and swallowed by large fish. They nest in colonies on rocky islets and cliffs._^<g_
Skuas obtain most of their food by chasing other seabirds and forcing them to drop or disgorge their prey, usually fish. Skuas also prey on eggs and chicks in seabird colonies. _^<g_
Fur seals have long, slender bodies, and can move swiftly through the water in pursuit of squid, their primary food. Their front flippers are shaped like oars and because they can turn their hind flippers forward, underneath their bodies, they can move quite well on land. _^<g_
_^<n__^<b_Locomotion:_^>b_ depends on species (legs, wings, fins, etc.; some are sessile)_^<n__^<b_Respiration:_^>b_ depends on species (lungs, gills, etc.)_^<n__^<b_Circulation:_^>b_ depends on species (open or closed system; some have hearts, others do not)_^<n__^<b_Diet:_^>b_ depends on species: some are plant-eaters (herbivorous), others are meat-eaters (carnivorous), still others can eat both plants and animals (omnivorous)_^<n__^<b_Development:_^>b_ fertilization and development are external in most species (most fish, for example); in others, fertilization is internal and eggs are either released to the outside (birds) or develop in the female's uterus (mammals)_^<n__^<b_Classification:_^>b_ all animals are members of the Kingdom Animalia_^<n__^<b_Number of species:_^>b_ more than 1 million_^<n__^<b_Largest:_^>b_ 100 feet long and 260,000 pounds in weight_^<n__^<b_Smallest:_^>b_ microscopic_^<n__^<g_
_^<n__^<b_Locomotion:_^>b_ 1 pair of legs for walking or swimming and, typically, 1 pair of wings for flight_^<n__^<b_Respiration:_^>b_ lungs_^<n__^<b_Circulation:_^>b_ closed system, 4-chambered heart (2 atria, 2 ventricles)_^<n__^<b_Diet:_^>b_ varied, depending on species_^<n__^<b_Development:_^>b_ fertilization is internal, development is external_^<n__^<b_Classification:_^>b_ class Aves, phylum Vertebrata_^<n__^<b_Number of species:_^>b_ more than 8,700_^<n__^<b_Largest:_^>b_ 8 feet tall_^<n__^<b_Smallest:_^>b_ 2.5 inches long, including bill and tail_^<n__^<g_
_^<n__^<b_Locomotion:_^>b_ 2 pairs of legs_^<n__^<b_Respiration:_^>b_ lungs_^<n__^<b_Circulation:_^>b_ closed system, four-chambered heart (2 atria, 2 ventricles)_^<n__^<b_Diet:_^>b_ carnivorous_^<n__^<b_Development:_^>b_ fertilization and development are internal_^<n__^<b_Classification:_^>b_ Felis catus catus, family Felidae, class Mammalia, phylum Vertebrata_^<n__^<b_Number of breeds:_^>b_ at least 26_^<n__^<b_Largest:_^>b_ 20 pounds or more_^<n__^<b_Smallest:_^>b_ about 5 pounds_^<n__^<g_
_^<n__^<b_Locomotion:_^>b_ 2 pairs of legs for walking, movement of tail for swimming_^<n__^<b_Respiration:_^>b_ lungs_^<n__^<b_Circulation:_^>b_ closed system_^<n__^<b_Diet:_^>b_ carnivorous_^<n__^<b_Classification:_^>b_ family Crocodylidae, class Reptilia, phylum Vertebrata_^<n__^<b_Number of species:_^>b_ 11_^<n__^<b_Largest:_^>b_ 20 feet or more in length_^<n__^<b_Smallest:_^>b_ about 5 feet long_^<n__^<g_
_^<n__^<b_Locomotion:_^>b_ 2 pairs of legs_^<n__^<b_Respiration:_^>b_ lungs_^<n__^<b_Circulation:_^>b_ closed system, 4-chambered heart (2 atria, 2 ventricles)_^<n__^<b_Diet:_^>b_ basically carnivorous_^<n__^<b_Development:_^>b_ fertilization and development are internal_^<n__^<b_Classification:_^>b_ Canis familiaris, family Canidae, class Mammalia, phylum Vertebrata_^<n__^<b_Number of breeds:_^>b_ about 140 recognized by the American Kennel Club_^<n__^<b_Largest:_^>b_ 35 inches at the shoulder and 220 pounds in weight_^<n__^<b_Smallest:_^>b_ 5 inches at the shoulder and 4 pounds in weight_^<n__^<g_
_^<n__^<b_Locomotion:_^>b_ typically, by contracting and relaxing a succession of muscle blocks, called myomeres, alternately on each side of the body_^<n__^<b_Respiration:_^>b_ typically, gills_^<n__^<b_Circulation:_^>b_ closed system, 2-chambered heart (upper atrium, lower ventricle), plus two accessory chambers_^<n__^<b_Diet:_^>b_ varies with the species_^<n__^<b_Development:_^>b_ fertilization and development typically external_^<n__^<b_Classification:_^>b_ classes Agnatha (jawless fish), Chondrichthyes (cartilaginous-skeleton fish), and Osteichthyes (bony-skeleton fish); phylum Vertebrata_^<n__^<b_Number of species:_^>b_ 20,000 or more (estimated)_^<n__^<b_Largest:_^>b_ 60 feet long and over 40,000 pounds in weight_^<n__^<b_Smallest:_^>b_ 0.5 inches long and about 0.05 ounce_^<n__^<g_
_^<n__^<b_Locomotion:_^>b_ tail in young, 2 pairs of legs in adult_^<n__^<b_Respiration:_^>b_ gills in young, lungs in adult_^<n__^<b_Circulation:_^>b_ closed system, 3-chambered (2 atria, 1 ventricle)_^<n__^<b_Diet:_^>b_ largely herbivorous as young, carnivorous as adults_^<n__^<b_Development:_^>b_ fertilization and development typically external_^<n__^<b_Classification:_^>b_ order Anura, class Amphibia, phylum Vertebrata_^<n__^<b_Number of species:_^>b_ more than 3,700 (including toads)_^<n__^<b_Largest:_^>b_ up to 39 inches in body length_^<n__^<b_Smallest:_^>b_ 0.5 inches in body length_^<n__^<g_
_^<n__^<b_Locomotion:_^>b_ 3 pairs of legs, 2 pairs of wings_^<n__^<b_Respiration:_^>b_ paired tubes called tracheae, which communicate with the outside through openings called stigmata_^<n__^<b_Circulation:_^>b_ open system, simple heart_^<n__^<b_Diet:_^>b_ herbivorous_^<n__^<b_Development:_^>b_ fertilization internal, development external_^<n__^<b_Classification:_^>b_ superfamilies Acridoidea (short-horned grasshoppers) and Tettigonioidea (long-horned grasshoppers), class Insecta, phylum Arthropoda_^<n__^<b_Number of species:_^>b_ about 5,000_^<n__^<b_Largest:_^>b_ 4 inches long with a wingspan of 6 inches_^<n__^<b_Smallest:_^>b_ less than 1/2 inch long_^<n__^<g_
_^<n__^<b_Locomotion:_^>b_ 2 pairs of legs_^<n__^<b_Respiration:_^>b_ lungs_^<n__^<b_Circulation:_^>b_ closed system, 4-chambered heart (2 atria, 2 ventricles)_^<n__^<b_Diet:_^>b_ herbivorous_^<n__^<b_Development:_^>b_ fertilization and development are internal_^<n__^<b_Classification:_^>b_ Equus caballus, family Equidae, class Mammalia, phylum Vertebrata_^<n__^<b_Number of breeds:_^>b_ about 100_^<n__^<b_Largest:_^>b_ 75 inches at the withers and 2,600 pounds in weight_^<n__^<b_Smallest:_^>b_ 40 inches at the withers and 300 pounds in weight_^<n__^<g_
_^<n__^<b_Locomotion:_^>b_ four legs_^<n__^<b_Respiration:_^>b_ lungs_^<n__^<b_Circulation:_^>b_ closed system, 4-chambered (2 atria, 2 ventricles)_^<n__^<b_Diet:_^>b_ carnivorous_^<n__^<b_Development:_^>b_ fertilization and development are internal_^<n__^<b_Classification:_^>b_ family Felidae, class Mammalia, phylum Vertebrata_^<n__^<b_Number of species:_^>b_ about 36_^<n__^<b_Largest:_^>b_ 9 feet long (excluding tail)_^<n__^<b_Smallest:_^>b_ 20 inches long (excluding tail)_^<n__^<g_
_^<n__^<b_Locomotion:_^>b_ varies with the species; four basic kinds: lateral (horizontal) undulation, concertina movement, sidewinding, and rectilinear movement_^<n__^<b_Respiration:_^>b_ lungs (the left lung is typically reduced in size or completely lacking)_^<n__^<b_Circulation:_^>b_ closed system, 3-chambered heart (2 atria, 1 ventricle)_^<n__^<b_Diet:_^>b_ carnivorous_^<n__^<b_Development:_^>b_ fertilization internal, development usually external_^<n__^<b_Classification:_^>b_ suborder Serpentes, order Squamata, class Reptilia, phylum Vertebrata_^<n__^<b_Number of species:_^>b_ 2,500 to 3,000_^<n__^<b_Largest:_^>b_ 30 feet or more in length_^<n__^<b_Smallest:_^>b_ 5 inches long_^<n__^<g_
_^<b_Tables_^>b__^<n__^<a!B37764_Endangered Species in the U.S., Selective List_^>a__^<n__^<a!B40315_Life Span of Selected Animals and Plants _^>a__^<n__^<g_
_^<n__^<a!T1371_animal_^>a__^<n__^<a!T1372_animal behavior_^>a__^<n__^<a!T1373_animal cognition_^>a__^<n__^<a!T1374_animal communication_^>a__^<n__^<a!T1375_animal courtship and mating_^>a__^<n__^<a!T15352_heart, animal_^>a__^<n__^<g_
_^<n__^<a!T3732_bird_^>a__^<n__^<a!T3742_birds of prey_^>a__^<n__^<a!T11780_feathers_^>a__^<n__^<a!T12245_flight_^>a__^<n__^<a!T13152_game birds_^>a__^<n__^<a!T25394_perching birds_^>a__^<n__^<a!T30422_songbirds_^>a__^<n__^<a!T30583_sparrow_^>a__^<n__^<g_
Leopard seals are the most ferocious of all seals, preying mainly on penguins but also on other birds and seals. They catch penguins by swimming underwater, then grabbing a bird by its feet and rump. Leopard seals live on the pack ice in summer and migrate north for the winter. _^<g_
Like all penguins, Adelie penguins cannot fly through the air, but they use their paddlelike wings to "fly" through the water. They feed on fish, squid, and shrimp - and in turn are preyed upon by seals. They nest in icy wastelands far from shore, the parents taking turns caring for the eggs. _^<g_
Emperor penguins feed on fish and squid. They breed on the Antarctic coast. The single egg is borne on the feet of the male parent, sheltered within a belly-skin pouch. Unattended eggs and chicks are prey to petrels and other predators._^<g_
The chinstrap penguin hunts by skimming rapidly along the water's surface, grabbing squid and fish without slowing down. Its tongue and mouth are lined with sharp, backward-pointing spines, which help the bird hold onto slippery prey._^<g_
The Weddell seal spends much of its time in the water, but occasionally crawls onto beaches or ice, moving clumsily over the surface. It also may spend time under the ice, obtaining air either through cracks in the ice or from air pockets. It feeds mainly on fish and squid._^<g_
Like all herring, Antarctic herring are an important part of ocean food chains. They are primary consumers, feeding on photosynthesizing plankton. In turn, they are eaten by secondary consumers such as various birds and seals._^<g_
Antarctic cod are also known as cod icefish. There are more than 50 species--roughly half the fish species living in the Antarctic. A glycoprotein in their blood enables some species to live beneath the ice._^<g_
Ross seals live on the outer edge of the pack ice. They have unusually large eyes and very streamlined bodies. Because they cannot turn their hind flippers forward to walk on land, they move awkwardly by hunching along._^<g_
Elephant seals - named for the male's long snout--are the largest carnivores, weighing nearly 7,500 pounds. Some of the young stay on the beach all year, but most adults move to the sea in fall and winter to feed on fish and squid, diving to depths of more than 500 feet._^<g_
Fish living amid the low water temperatures of the Antarctic must be able to prevent ice crystals from forming in their tissues. A protein-carbohydrate compound in their blood acts as an antifreeze, enabling them to do this._^<g_
The dovekie is a small auk that nests in vast colonies on Arctic sea cliffs. It feeds almost exclusively on small marine crustaceans. Like other auks, dovekies are poor flyers because of their small wings. Their structure is better adapted for diving and pursuit under water._^<g_
Common murres breed in huge, densely packed colonies on ledges and steep cliffs. A female lays a single large egg on bare rock. The egg is pear-shaped; if dislodged, it tends to roll in a half circle, thus preventing breakage. Common murres prey mainly on fish, which they catch by "flying" underwater._^<g_
A heavy, powerful bird of prey with a hooked beak and sharp claws, the gyrfalcon eats mainly birds, especially ptarmigans, which it often catches in flight. The gyrfalcon's nest is an untidy platform of sticks and bones, usually on a high cliff ledge._^<g_
Caribou, or reindeer, feed on lichens, herbs, leaves, and buds. They have denser fur than other deer, which helps protect them against the arctic cold. They have unusually large feet and crescent-shaped hooves, which facilitate travel over snow-covered and boggy ground. _^<g_
Ringed seals, which live near the ice edge, propel themselves through the water by moving their hind flippers up and down. They also can stay upright in the water, treading water with their hind flippers. On land, they move clumsily, becoming easy prey for predators._^<g_
The arctic fox has tiny ears, which radiate less heat than large ears, thus helping the animal conserve body heat. It follows polar bears, eating the remains of the bears' kills. This can be a dangerous practice, since polar bears eat arctic foxes._^<g_
The gray, or timber wolf, often hunts in packs, attacking large prey that an individual or pair of wolves could not bring down on its own. Wolves can survive without food for several days, and then may gorge up to one-fifth their body weight at a single feeding._^<g_
Their white fur is effective camouflage for polar bears, helping them steal up unnoticed on prey. They are extremely skilled at catching seals--their principal food--and also eat foxes, birds, and other animals. The dense fur plus a thick layer of fat beneath the skin act as insulation against the cold._^<g_
Broad furry paws help the snowshoe hare move easily across the snow. Its coat is reddish-brown in summer, then turns white for the winter. The seasonal changes help the hare blend into its surroundings, thereby avoiding notice by enemies such as lynx._^<g_
The walrus spends most of its time in shallow open waters near the edge of the polar ice. The soles and palms of its limbs are very rough, providing traction on ice. To feed, a walrus will descend as much as 300 feet, head down, and use its tusks to grab mollusks, starfish, and other animals from the ocean floor._^<g_
Musk oxen have a very dense coat that hangs down from the body. They live in herds. When attacked, a herd forms a compact circle, with the young in the center and the horned adults facing outward. This provides effective defense against wolves, their chief natural enemy._^<g_
Active during the day, the snowy owl feeds mainly on mice and lemmings, but it also preys on a variety of birds. It summers on the tundra, where it builds its nest and raises its young, but migrates south for the winter. _^<g_
Short-tailed weasels are extremely agile and fast-moving. They are skilled predators, feeding mainly on mice, killing with a single bite to the back of the neck. In turn, the weasels are food for foxes, owls, eagles, and other animals._^<g_
Wolverines are ferocious animals that can kill their own prey but prefer to feed on carrion. They are excellent climbers and swimmers, and ward off enemies with a skunklike smell. Their thick, long fur is effective insulation against the arctic cold._^<g_
Most of the Arctic consists of an ice-covered ocean. On land, only the top layer--to a depth of some 3 feet--thaws in the short summer season. Beneath is permafrost, or perennially frozen ground. This prevents ground water from percolating downward; the water stays on the ground's surface or runs into rivers._^<g_
Because temperatures are below freezing most of the time, most precipitation in the Arctic falls as snow. Some areas are covered with snow and ice year-round; elsewhere, the snow melts during the short summer, allowing growth of low-lying mosses, lichens, and other photosynthetic organisms._^<g_
Seals have long streamlined bodies, with limbs modified into flippers--adaptations for a life spent mostly in the water. The freezing and melting of the ice causes harp seals to migrate to breeding grounds off of Greenland, Newfoundland, and the Gulf of St. Lawrence._^<g_
Polar cod live in arctic waters at temperatures below 5 C. During the summer they live at the edge of the pack ice; in fall, they move near to shore, where they breed in the winter. The polar cod's diet consists mainly of plankton. In turn, polar cod are important prey for seals and toothed whales._^<g_
Small, slender fish, smelts are an important food source for larger predatory fishes._^<g_
_^<n__^<b_Definition:_^>b_ an Arctic biome with long, cold winters and a year-round layer of drifting ice on the Arctic Ocean_^<n__^<b_Geographic region:_^>b_ within the Arctic Circle_^<n__^<b_Terrain:_^>b_ generally low-lying along edges of continents, rugged and mountainous on some islands; habitat includes Arctic Ocean and seas_^<n__^<b_Climate:_^>b_ long, cold winters and short, cool summers_^<n__^<b_Precipitation:_^>b_ generally less than 10 inches annually_^<n__^<b_Average annual temperature:_^>b_ below 32 degrees F_^<n__^<b_Soil:_^>b_ thin, with low fertility; top layer underlain by permafrost_^<n__^<b_Dominant vegetation:_^>b_ algae (seas)_^<n__^<g_
_^<n__^<a!T1718_Arctic_^>a__^<n__^<a!T1720_Arctic Ocean_^>a__^<n__^<a!T13741_glaciers and glaciation_^>a__^<n__^<a!T14786_habitat_^>a__^<n__^<a!T16641_iceberg_^>a__^<n__^<a!T24737_pack ice_^>a__^<n__^<a!T25149_patterned ground_^>a__^<n__^<a!T25451_permafrost_^>a__^<n__^<a!T26123_polar climate_^>a__^<n__^<a!T31744_talus_^>a__^<n__^<g_
The blubber of the seal, a thick subcutaneous layer of fat, may make up nearly half of its body weight. It provides insulation, buoyancy, and reserve energy during lactation and the fasting periods characteristic of most seals._^<g_
_^<n__^<b_Definition:_^>b_ a biome on and around the Antarctic continent, supported by the sea_^<n__^<b_Geographic region:_^>b_ mostly within the Antarctic Circle_^<n__^<b_Terrain:_^>b_ rocky, mostly covered with ice; biome includes surrounding Antarctic Ocean, with seasonal or perennial sea ice_^<n__^<b_Climate:_^>b_ long, cold winters and short, cool summers_^<n__^<b_Precipitation:_^>b_ 20 to 40 inches (coastal areas)_^<n__^<b_Average annual temperature:_^>b_ 5 to 14 degrees F (coastal areas)_^<n__^<b_Soil:_^>b_ thin, commonly alkaline, with little humus_^<n__^<b_Dominant vegetation:_^>b_ lichens and mosses (land), algae (sea)_^<n__^<g_
_^<n__^<a!T1448_Antarctica_^>a__^<n__^<a!T13741_glaciers and glaciation_^>a__^<n__^<a!T14786_habitat_^>a__^<n__^<a!T16641_iceberg_^>a__^<n__^<a!T35899_zooplankton_^>a__^<n__^<g_
_^<n__^<b_Definition:_^>b_ dry deserts are regions in which precipitation is regularly too light to support either forests or complete grass cover_^<n__^<b_Geographic regions:_^>b_ typically between approximately 20 and 30 degrees of latitude, in both the Northern and Southern hemispheres_^<n__^<b_Terrain:_^>b_ varied_^<n__^<b_Climate:_^>b_ arid, with great range of temperatures within a specific desert, both annually and daily_^<n__^<b_Precipitation:_^>b_ generally less than 10 inches a year, with great variation from year to year; amount of precipitation does not equal potential evaporation_^<n__^<b_Average annual temperatures:_^>b_ vary depending on latitude_^<n__^<b_Soil:_^>b_ light-colored, shallow, low in organic matter_^<n__^<b_Dominant vegetation:_^>b_ varied, but adapted to the stresses imposed by aridity_^<n__^<g_
The turkey vulture is a graceful flyer. It spends many hours each day gliding on thermals, searching for food by sight and smell. It feeds almost entirely on carrion. Hungry vultures quickly cleanse the habitat of the remains of dead animals._^<g_
The pronghorn is the fastest mammal in the Western Hemisphere, reaching speeds of more than 50 miles per hour for short spurts. Its keen eyesight enables it to see a moving predator as far as 4 miles away. It feeds on cacti and leaves of desert plants._^<g_
The saguaro is the tallest cactus, attaining heights up to 60 feet. It survives long periods of dryness by storing water in its trunk and stems. Its wide-spreading roots, which grow very close to the surface, can rapidly soak up water even during very light rainfalls._^<g_
Smaller and more agile than other skunks, spotted skunks usually stay in burrows or rocky crevices during the daytime. They emerge at dusk, as temperatures cool, to search for worms, insects, birds and their eggs, and small mammals and their young._^<g_
Barrel cacti, shaped like cylinders or flattened globes, have pronounced vertical pleats, which expand like the bellows of an accordion after a rainfall, as the plants soak up water. Most types of barrel cacti have numerous spines, which protect the plants from hungry and thirsty animals._^<g_
Prickly pear cacti, like other cacti, have no leaves, since these lose a lot of water through transpiration. Instead, cacti carry out photosynthesis in their green stems. Prickly pear cacti produce large red fruits, which are favored by gophers as a source of both food and water._^<g_
Bobcats are active at night, using their excellent eyesight and hearing to detect prey. They hunt for rodents, rabbits, other small mammals, and birds, and occasionally attack large mammals. They are solitary except during the mating season._^<g_
Desert tortoises stay in cool underground burrows to escape the heat of the desert day, then come out at dusk to feed on tough grasses and other vegetation. They move slowly, expending as little energy as possible. _^<g_
The American badger is an aggressive animal, with sharp teeth and claws, heavy neck muscles, and leathery skin. It attacks gophers, ground squirrels, and rodents by tearing apart their burrows and eating the prey in their underground homes._^<g_
Collared lizards have long limbs and fringes along the toes to aid them in getting a purchase on shifting sands. They are active during the day, jumping from rock to rock in search of insects and other prey._^<g_
A scorpion has a poisonous sting at the end of the abdomen, which it holds above its back. It uses the poison to immobilize insects, spiders, and other small animals. Scorpions are solitary, nocturnal creatures that attack each other as readily as any other suitable prey._^<g_
Costa's hummingbirds use their slender, pointed bill to feed on nectar and insects and spiders found in desert flowers. The flowers, in turn, depend on the hummingbirds for pollination. The birds often build their cup-shaped nests in branching cacti and dead yuccas. _^<g_
The claret-cup cactus has a ribbed stem protected by barbed bristles. Large bright red flowers are borne below the tip of the stem. The flowers give rise to fleshy fruits that are favorite foods of small desert mammals._^<g_
Gambel's quail lives in thickets of mesquite and other plants, which offer both shade and protection. Its nest is a hollow scraped in the ground at the base of a plant. It eats mesquite and other seeds, as well as the fruits of prickly pear, barrel, and other cacti. _^<g_
_^<n__^<b_Location:_^>b_ Chartres, France, about 90 km (55 mi) southwest of Paris. Constructed on the site of an early Christian basilica that burned down in 1194_^<n__^<b_Purpose:_^>b_ A French Gothic cathedral_^<n__^<b_Benefactors (rebuilding):_^>b_ The cooperative support of nobles and peasants, through their donated money and labor_^<n__^<b_Date completed (rebuilding):_^>b_ 1220_^<n__^<b_Duration of reconstruction:_^>b_ 26 years_^<n__^<b_Dates and nature of major renovations:_^>b__^<n__^<o!E345__^<o!E345_1140-50 - Sculptured bays of the triple Royal Portal were added._^<n__^<o!E345__^<o!E345_1155 - Three magnificent stained-glass windows were added above the triple Royal Portal._^<n__^<o!E345__^<o!E345_1194 - A fire ruined most of the cathedral. Reconstruction was begun._^<n__^<o!E345__^<o!E345_1220 - Reconstruction was completed. The new cathedral had hundreds of stained glass windows and statues._^<n__^<o!E345__^<o!E345_16th century - The ornate North Tower was added._^<n__^<g_
_^<n__^<b_Location:_^>b_ Between the Esquiline and Palatine hills in Rome, Italy_^<n__^<b_Purpose:_^>b_ An amphitheater for the public staging of combat contests and other functions _^<n__^<b_Patrons:_^>b_ Roman emperors Vespasian and Titus_^<n__^<b_Date completed:_^>b_ AD 80_^<n__^<b_Duration of construction:_^>b_ 11 years_^<n__^<b_Building details:_^>b__^<n__^<o!E345__^<o!E345_Number of stories - 4_^<n__^<o!E345__^<o!E345_Height - 49 m (160 ft)_^<n__^<o!E345__^<o!E345_Length - 615 m (118 ft)_^<n__^<o!E345__^<o!E345_Width - 156 m (510 ft)_^<n__^<o!E345__^<o!E345_Arena area - 86 m by 54 m (280 ft by 175 ft)_^<n__^<o!E345__^<o!E345_Seating capacity - 50,000_^<n__^<o!E345__^<o!E345_Exterior wall material - travertine_^<n__^<o!E345__^<o!E345_Interior wall material - tufa_^<n__^<o!E345__^<o!E345_Ramped seating vault material - monolithic concrete_^<n__^<g_
The western diamondback rattlesnake grows to lengths of 80 inches or more. It escapes the summer heat by hunting for mice, birds, and other prey at night. When it feels threatened, it lifts its tail and shakes the rattle, creating a sound that can be heard more than 100 feet away._^<g_
_^<n__^<b_Location:_^>b_ On the west bank of the Nile, situated south of the delta, between Hawara and Abu Ruwaysh_^<n__^<b_Purpose:_^>b_ A funerary monument built for the pharaoh Khufu (Cheops) and his closest relatives_^<n__^<b_Date completed:_^>b_ 2500 BC_^<n__^<b_Duration of construction:_^>b_ approximately 20 years_^<n__^<b_Building details:_^>b__^<n__^<o!E345__^<o!E345_Length of sides at the base - 230 m (756 ft)_^<n__^<o!E345__^<o!E345_Height (when completed) - 147 m (482 ft)_^<n__^<o!E345__^<o!E345_Number of stone blocks - 2.5 million, each weighing 2.5 metric tons_^<n__^<o!E345__^<o!E345_Original outer facing material - limestone_^<n__^<g_
_^<n__^<b_Location:_^>b_ On a 300-ft cliff overlooking the Seine River near Rouen, France_^<n__^<b_Purpose:_^>b_ A safe fortress for the French domains of England's Richard I (the Lion-Hearted)_^<n__^<b_Designer:_^>b_ King Richard I of England_^<n__^<b_Date completed:_^>b_ 1196_^<n__^<b_Note:_^>b_ The fortress served its purpose for several years, but after Richard's death, Philip II of France laid siege to it. The castle was demolished in a massive assault in March 1204, and three months later Rouen fell to the French._^<n__^<g_
Kangaroo rats drink little water, deriving most of what they require from their food. They use their cheek pouches to carry surplus food to the burrow for future use. Sensitive hearing enables kangaroo rats to elude predators such as rattlesnakes._^<g_
_^<n__^<b_Location:_^>b_ Atop the Acropolis in Athens, Greece_^<n__^<b_Purpose:_^>b_ A temple dedicated to Athena Parthenos (Athena the Warrior Maiden)_^<n__^<b_Architect:_^>b_ 5th-century Greek architects Ictinus and Callicrates, with sculpture by Phidias, considered the greatest of the ancient Greek sculptors_^<n__^<b_Date completed:_^>b_ 431 BC_^<n__^<b_Duration of construction:_^>b_ 17 years_^<n__^<b_Notable occupations of the Parthenon:_^>b__^<n__^<o!E345__^<o!E345_Athens City State - used building as a temple_^<n__^<o!E345__^<o!E345_Empire of Alexander the Great - used building as a temple_^<n__^<o!E345__^<o!E345_Roman Empire - used building as a church_^<n__^<o!E345__^<o!E345_Byzantine Empire - used building as a church_^<n__^<o!E345__^<o!E345_Ottoman Empire - used the building as a Turkish powder magazine_^<n__^<b_Notable events:_^>b__^<n__^<o!E345__^<o!E345_Sept. 16, 1687 - a direct hit by Venetian artillery caused the powder in the Parthenon to explode, scattering debris across the Acropolis._^<n__^<o!E345__^<o!E345_1802-03 - Some building remnants were taken to France by the duc de Choiseul, while most of the material was sent to Britain by the 7th earl of Elgin._^<n__^<o!E345__^<o!E345_1922-23 - Greek archaeologist Nicolas Balanos collected the remaining fragments of the temple and restored a number of columns and parts of the entablature that they carried._^<n__^<g_
_^<n__^<b_Location:_^>b_ Liberty Island in the New York City harbor_^<n__^<b_Purpose: _^>b_A gift from the French to the American people to honor the 1876 centennial celebration_^<n__^<b_Exterior designer:_^>b_ Frederic Auguste Bartholdi_^<n__^<b_Interior support designer:_^>b_ Gustave Eiffel_^<n__^<b_Pedestal designer:_^>b_ Richard Morris Hunt_^<n__^<b_Date completed:_^>b_ 1884_^<n__^<b_Duration of construction:_^>b_ 9 years_^<n__^<b_Notable dates in the statue's construction:_^>b__^<n__^<o!E345__^<o!E345_1875 - Frederic Auguste Bartholdi's monumental design is commissioned by the French government to be presented to the American public as a gift to honor the American centennial._^<n__^<o!E345__^<o!E345_1884 - The structure is completed and delivered, in sections, to the United States._^<n__^<o!E345__^<o!E345_1884 - The torch is displayed at the World's Fair in Philadelphia to help raise funds to assemble the statue in the New York Harbor._^<n__^<o!E345__^<o!E345_1886 - The statue is unveiled._^<n__^<o!E345__^<o!E345_1903 - The famous sonnet by Emma Lazarus, "The New Colossus," is inscribed on the base of the statue._^<n__^<o!E345__^<o!E345_1986 - Torch with new gilded flame and reinforced interior support are added as part of the statue's centennial._^<n__^<g_
_^<n__^<b_Location:_^>b_ On the Jumna River in Agra, India_^<n__^<b_Purpose:_^>b_ A representation of the throne of God in paradise and a mausoleum for the emperor's beloved consort Arjumand Banu Begum_^<n__^<b_Designer:_^>b_ Shah Jahan, Mogul emperor of India (r. 1628-58)_^<n__^<b_Date completed:_^>b_ 1648_^<n__^<b_Duration of construction:_^>b_ 17 years_^<n__^<b_Building details:_^>b__^<n__^<o!E345__^<o!E345_Height - 57 m (187 ft)_^<n__^<o!E345__^<o!E345_Platform area - 29 sq m (313 sq ft)_^<n__^<o!E345__^<o!E345_Symmetry - the domed structure is perfectly symmetrical along four axes_^<n__^<o!E345__^<o!E345_Mausoleum facade material - white marble_^<n__^<o!E345__^<o!E345_Surrounding tower facade material - red sandstone_^<n__^<g_
Pack rats (also known as wood rats) gained their name from their habit of packing non-edible objects into their dens. Desert pack rats build rounded nests 2 to 4 feet high amid cacti, yucca, and brush._^<g_
_^<n__^<b_Location:_^>b_ Near the banks of the Potomac River in Washington, D.C._^<n__^<b_Purpose:_^>b_ Residence for the president of the United States_^<n__^<b_Architect:_^>b_ James Hoban_^<n__^<b_Date completed:_^>b_ 1800_^<n__^<b_Duration of construction:_^>b_ 8 years_^<n__^<b_Dates and nature of major renovations:_^>b__^<n__^<o!E345__^<o!E345_1807 - Benjamin Latrobe, the principal architect of the Capitol, added pavilions at either end of the building._^<n__^<o!E345__^<o!E345_1815 - Rebuilt by Hoban after it was burned by the British (1814) in the War of 1812._^<n__^<o!E345__^<o!E345_1826 - Hoban added the semicircular South Portico proposed by Latrobe._^<n__^<o!E345__^<o!E345_1829 - Hoban completed the rectangular North Portico, also designed by Latrobe._^<n__^<o!E345__^<o!E345_1902 - Architecture firm McKim, Mead, and White added the East Gallery and the Executive Office Wing._^<n__^<o!E345__^<o!E345_1948 - Deemed structurally unsound, the building was gutted and its interior structure replaced with steel framing._^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P49130_Chartres Cathedral, France_^>a__^<n__^<a!P38950_Colosseum, Rome_^>a__^<n__^<a!P39165_Parthenon, Athens_^>a__^<n__^<a!P38900_Pyramids at Giza, Egypt_^>a__^<n__^<a!P39315_Statue of Liberty, New York_^>a__^<n__^<a!P39026_Taj Mahal_^>a__^<n__^<a!P46369_White House, Washington, D.C._^>a__^<n__^<g_
Pocket mice have fur-lined external cheek pouches for carrying food back to their burrows. They live mainly on seeds and other plant products, and obtain all the water they need from their food._^<g_
_^<b_Pictures_^>b__^<n__^<a!P39006_Pyramid of Khafre, Egypt_^>a__^<n__^<a!P38900_Pyramids of Giza_^>a__^<n__^<a!P46909_Pyramids of King Zoser_^>a__^<n__^<a!P37390_Sphinx_^>a__^<n__^<a!P37076_Pyramids of Egypt_^>a__^<n__^<g__^<b_Map_^>b__^<n__^<a!M50433_Egypt, Ancient_^>a__^<n__^<g_
_^<b_Picture_^>b__^<n__^<a!P45311_Richard I, king of England_^>a__^<n__^<g_
_^<b_Picture_^>b__^<n__^<a!P48214_Capitol of the United States, Washington, D.C. _^>a__^<n__^<g__^<b_Map_^>b__^<n__^<a!M44097_Washington, D.C., City Center_^>a__^<n__^<g_
_^<n__^<a!T1713_architecture_^>a__^<n__^<a!T6122_castle_^>a__^<n__^<a!T10686_Egypt, ancient_^>a__^<n__^<a!T14085_Gothic art and architecture_^>a__^<n__^<a!T14338_Greek architecture_^>a__^<n__^<a!T16803_Indian art and architecture_^>a__^<n__^<a!T23362_neoclassicism (art)_^>a__^<n__^<a!T27983_Roman art and architecture_^>a__^<n__^<a!T29215_sculpture_^>a__^<n__^<g_
_^<n__^<a!T1139_Amiens Cathedral_^>a__^<n__^<a!T1691_arch and vault_^>a__^<n__^<a!T6655_Chartres_^>a__^<n__^<a!T6656_Chartres Cathedral_^>a__^<n__^<a!T7339_clerestory_^>a__^<n__^<a!T14085_Gothic art and architecture_^>a__^<n__^<a!T23273_nave_^>a__^<n__^<a!T27465_Reims Cathedral_^>a__^<n__^<a!T30815_stained glass_^>a__^<n__^<a!T32969_triforium_^>a__^<n__^<g_
_^<n__^<a!T1685_arcade_^>a__^<n__^<a!T1691_arch and vault_^>a__^<n__^<a!T7660_Colosseum_^>a__^<n__^<a!T13747_gladiators_^>a__^<n__^<a!T27983_Roman art and architecture_^>a__^<n__^<a!T28008_Rome (Italy)_^>a__^<n__^<a!T28010_Rome, ancient_^>a__^<n__^<a!T32593_Titus, Roman Emperor_^>a__^<n__^<a!T33921_Vespasian, Roman Emperor_^>a__^<n__^<g_
_^<n__^<a!T26909_pyramids_^>a__^<n__^<a!T10685_Egypt_^>a__^<n__^<a!T10686_Egypt, ancient_^>a__^<n__^<a!T18322_Khufu, King of Egypt_^>a__^<n__^<a!T25602_pharaoh_^>a__^<n__^<a!T13737_Giza_^>a__^<n__^<a!T5429_Cairo (Egypt)_^>a__^<n__^<a!T8852_Dahshur_^>a__^<n__^<a!T16734_Imhotep_^>a__^<n__^<g_
_^<n__^<a!T6122_castle_^>a__^<n__^<a!T6668_chateau_^>a__^<n__^<a!T12519_fortification_^>a__^<n__^<a!T21898_Middle Ages_^>a__^<n__^<a!T25649_Philip II, King of France (Philip Augustus)_^>a__^<n__^<a!T27675_Richard I, King of England_^>a__^<n__^<a!T28136_Rouen_^>a__^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P41121_Bobcat_^>a__^<n__^<a!P49023_Pronghorn_^>a__^<n__^<a!P49249_Saguaro National Monument, Arizona_^>a__^<n__^<a!P49199_Scorpion_^>a__^<n__^<a!P39612_Tortoise, desert _^>a__^<n__^<g_
_^<n__^<a!T2869_Bartholdi, Frederic Auguste_^>a__^<n__^<a!T10703_Eiffel, Alexandre Gustave_^>a__^<n__^<a!T10913_Ellis Island_^>a__^<n__^<a!T16425_Hunt, Richard Morris_^>a__^<n__^<a!T19245_Lazarus, Emma_^>a__^<n__^<a!T30903_Statue of Liberty_^>a__^<n__^<a!T30904_Statue of Liberty National Monument_^>a__^<n__^<g_
_^<n__^<a!T475_Agra_^>a__^<n__^<a!T16382_Humayun, Mogul Emperor of India_^>a__^<n__^<a!T16803_Indian art and architecture_^>a__^<n__^<a!T17196_Islamic art and architecture_^>a__^<n__^<a!T22249_Mogul art and architecture_^>a__^<n__^<a!T29556_Shah Jahan, Mogul Emperor of India_^>a__^<n__^<a!T31714_Taj Mahal_^>a__^<n__^<g_
_^<n__^<a!T5786_Capitol of the United States_^>a__^<n__^<a!T15889_Hoban, James_^>a__^<n__^<a!T23362_neoclassicism (art)_^>a__^<n__^<a!T26501_president of the United States_^>a__^<n__^<a!T34493_Washington, D.C._^>a__^<n__^<a!T34915_White House_^>a__^<n__^<g_
_^<n__^<a!T5383_cacti and other succulents_^>a__^<n__^<a!T9460_desert_^>a__^<n__^<a!T9461_desert life_^>a__^<n__^<a!T10390_dust devil_^>a__^<n__^<a!T14786_habitat_^>a__^<n__^<a!T28710_sand dune_^>a__^<n__^<a!T28728_sandstorm and dust storm_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D42236_--Famous Buildings_^>a__^<n__^<b_----Chartres Cathedral_^>b__^<n__^<a!D43604_----Colosseum_^>a__^<n__^<a!D43159_----Great Pyramid_^>a__^<n__^<a!D43889_----Medieval Castle_^>a__^<n__^<a!D43478_----Parthenon_^>a__^<n__^<a!D44088_----Statue of Liberty_^>a__^<n__^<a!D43956_----Taj Mahal_^>a__^<n__^<a!D44156_----White House_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D42236_--Famous Buildings_^>a__^<n__^<a!D43743_----Chartres Cathedral_^>a__^<n__^<b_----Colosseum_^>b__^<n__^<a!D43159_----Great Pyramid_^>a__^<n__^<a!D43889_----Medieval Castle_^>a__^<n__^<a!D43478_----Parthenon_^>a__^<n__^<a!D44088_----Statue of Liberty_^>a__^<n__^<a!D43956_----Taj Mahal_^>a__^<n__^<a!D44156_----White House_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D42236_--Famous Buildings_^>a__^<n__^<a!D43743_----Chartres Cathedral_^>a__^<n__^<a!D43604_----Colosseum_^>a__^<n__^<b_----Great Pyramid_^>b__^<n__^<a!D43889_----Medieval Castle_^>a__^<n__^<a!D43478_----Parthenon_^>a__^<n__^<a!D44088_----Statue of Liberty_^>a__^<n__^<a!D43956_----Taj Mahal_^>a__^<n__^<a!D44156_----White House_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D42236_--Famous Buildings_^>a__^<n__^<a!D43743_----Chartres Cathedral_^>a__^<n__^<a!D43604_----Colosseum_^>a__^<n__^<a!D43159_----Great Pyramid_^>a__^<n__^<b_----Medieval Castle_^>b__^<n__^<a!D43478_----Parthenon_^>a__^<n__^<a!D44088_----Statue of Liberty_^>a__^<n__^<a!D43956_----Taj Mahal_^>a__^<n__^<a!D44156_----White House_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D42236_--Famous Buildings_^>a__^<n__^<a!D43743_----Chartres Cathedral_^>a__^<n__^<a!D43604_----Colosseum_^>a__^<n__^<a!D43159_----Great Pyramid_^>a__^<n__^<a!D43889_----Medieval Castle_^>a__^<n__^<b_----Parthenon_^>b__^<n__^<a!D44088_----Statue of Liberty_^>a__^<n__^<a!D43956_----Taj Mahal_^>a__^<n__^<a!D44156_----White House_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D42236_--Famous Buildings_^>a__^<n__^<a!D43743_----Chartres Cathedral_^>a__^<n__^<a!D43604_----Colosseum_^>a__^<n__^<a!D43159_----Great Pyramid_^>a__^<n__^<a!D43889_----Medieval Castle_^>a__^<n__^<a!D43478_----Parthenon_^>a__^<n__^<b_----Statue of Liberty_^>b__^<n__^<a!D43956_----Taj Mahal_^>a__^<n__^<a!D44156_----White House_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D42236_--Famous Buildings_^>a__^<n__^<a!D43743_----Chartres Cathedral_^>a__^<n__^<a!D43604_----Colosseum_^>a__^<n__^<a!D43159_----Great Pyramid_^>a__^<n__^<a!D43889_----Medieval Castle_^>a__^<n__^<a!D43478_----Parthenon_^>a__^<n__^<a!D44088_----Statue of Liberty_^>a__^<n__^<b_----Taj Mahal_^>b__^<n__^<a!D44156_----White House_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D42236_--Famous Buildings_^>a__^<n__^<a!D43743_----Chartres Cathedral_^>a__^<n__^<a!D43604_----Colosseum_^>a__^<n__^<a!D43159_----Great Pyramid_^>a__^<n__^<a!D43889_----Medieval Castle_^>a__^<n__^<a!D43478_----Parthenon_^>a__^<n__^<a!D44088_----Statue of Liberty_^>a__^<n__^<a!D43956_----Taj Mahal_^>a__^<n__^<b_----White House_^>b__^<n__^<g_
_^<n__^<b_Definition:_^>b_ a biome dominated by trees_^<n__^<b_Geographic region:_^>b_ subarctic, temperate, and tropical areas of the world_^<n__^<b_Terrain:_^>b_ varied_^<n__^<b_Climate:_^>b_ varied, depending on latitude and elevation_^<n__^<b_Precipitation:_^>b_ varied--e.g., 30 to 60 inches (northern deciduous); 15 to 30 inches (northern coniferous); 30 to 100 inches (tropical deciduous); 40 to 80 inches (tropical montane)_^<n__^<b_Average annual temperatures:_^>b_ varied_^<n__^<b_Soil:_^>b_ generally rich in organic matter_^<n__^<b_Dominant vegetation:_^>b_ trees; typically, conifer forests are found in cooler, drier environments whereas broad-leaved forests are found in warmer, moister environments_^<n__^<g_
The wings of Eurasian sparrow hawks are shorter and narrower than the wings of other birds of prey, making it easier to navigate through dense forests in pursuit of prey. These birds feed mainly on birds, but also capture insects and small mammals. Those that summer in northern climes migrate southward to warmer places in autumn._^<g_
Black woodpeckers perform thousands of pecks per day as they search for bark- and wood-boring insects in forest trees. Tits, nuthatches, and tree creepers also feed on insects pried loose by the woodpeckers. Together, the birds play an important role in regulating the insect populations._^<g_
Tawny owls are night hunters, depending on their excellent hearing and enormous black eyes to find prey. They devour mice and sleepy songbirds that they startle from nighttime roosts. At dawn, the owls retreat to their own roosts, usually on high branches of tall trees._^<g_
The European red squirrel, like other tree squirrels, takes refuge from enemies and builds nests in trees. It eats foods produced by trees, such as fruits, buds, and the bark of twigs. It has many uses for is bushy tail, including blanket and umbrella._^<g_
The green woodpecker uses its long tongue--which can protrude a considerable distance out of the mouth and which has a spiny tip--to lick ants off the ground and from branches and tree trunks. In winter, when ants remain in their nests to keep warm, the woodpecker scratches open the nests to feast._^<g_
Fallow deer feed on grass, leaves, and other plant matter. They are gregarious animals, generally spending most of their time in groups. They depend on their excellent senses of sight, smell, and hearing to detect danger, and quickly flee at the sign of wolves and other predators._^<g_
Bracket fungi are common agents of wood decomposition in forests. They grow on both live and dead trees. Those growing on living trees typically obtain nutrients only from dead wood cells, but they produce chemicals that may kill living cells and lead to the death of the tree._^<g_
The peacock butterfly is a common species in European habitats, and among the first butterflies to appear in early spring, since the adults live over the winter. Like all butterflies, it feeds exclusively on nectar, which it drinks through a long tube formed by the joining of mouthparts._^<g_
The European wild rabbit digs burrows that may form extensive interconnecting systems known as warrens. These serve as homes in which the rabbits are safe and can rest. The rabbits are active primarily from dusk to dawn, feeding on low-lying vegetation._^<g_
The English oak is a sturdy tree that grows to heights of 100 feet or more. The crowns of neighboring trees may form an almost complete cover so that little direct sunlight reaches the forest floor in summer. The tree's nuts, called acorns, are a favorite food of squirrels._^<g_
In spring, when the ground is damp and before the oaks and other deciduous trees have leafed out, the forest floor is colored by blossoming bluebells and other wildflowers. _^<g_
Wild boars rest during the day, often under a rock ledge or fallen tree, or beneath dense vegetation. At night they forage, using their tusks to tear the ground in search of roots and tubers. The young have brown coats horizontally striped with white; as they mature they develop the adult coloring._^<g_
Primroses grow in shady spots that have moist, loamy soil. They die back each winter but renew themselves from buds on the rootstock each spring. They bloom in spring, depending on insects to carry pollen from one flower to another._^<g_
Great tits are active during the day, feeding mainly on insects, spiders, fruit, seeds, and nuts. They have a streak of curiosity that often leads to tasty tidbits. Companies in Britain had to create bird-proof bottle caps after tits discovered how to pry open the tops of milk bottles left on front steps by the milkman._^<g_
Bramble is a common name for prickly-stemmed berry bushes such as raspberries. Underground parts are perennial while the stems, called canes, live for two years. Flowers and fruits are produced on second-year canes. The flowers are usually white, and pollinated by insects._^<g_
Badgers use their broad feet and long claws to dig underground homes, constantly remodeling by adding new rooms, entrances, and exits. They rest in the burrows during the day, then hunt at night, eating both plants and small animals._^<g_
Mushrooms, like other fungi, do not contain chlorophyll and cannot manufacture their own food. Most of them obtain nourishment from decaying organic matter such as dead wood, humus, and manure. They are most likely to be seen when the weather is warm and moist._^<g_
Also known as lords-and-ladies, cuckoopint grows a foot high and sprouts large purple-spotted foliage. The flower is followed by a cluster of poisonous red berries. The leaves and corms (bulblike parts of the stem) are acrid. Starch in the ripened corms is used as food._^<g_
The mole's body is highly specialized for digging through the ground. Its forefeet are powerfully built digging instruments with a spadelike shape. Although most moles spend their lives tunneling underground, some species are also semiaquatic._^<g_
Meadow voles eat almost their own weight in vegetable matter each day, consuming seeds, bark, roots, and leaves. They can give birth at five weeks of age and can produce a new litter almost every three weeks. Their population is kept in check by their many enemies. Meadow voles constitute a major food source for many important fur-bearing animals._^<g_
_^<n__^<a!T9242_deciduous plant_^>a__^<n__^<a!T12450_forests and forestry_^>a__^<n__^<a!T14786_habitat_^>a__^<n__^<a!T31705_taiga_^>a__^<n__^<a!T32921_tree_^>a__^<n__^<g_
Black-footed ferrets are mostly nocturnal and feed almost exclusively on prairie dogs. They move into a colony of these rodents, using the burrows for shelter and the occupants for food. When the colony has been depleted, the ferrets move to a new colony._^<g_
Wilson's phalarope is a freshwater bird, summering on North American grasslands, then migrating southward for the winter. It typically builds its grass-lined nest near the edge of quiet shallow waters. It uses its long beak to grab mosquito larvae, diving beetles, and other food. _^<g_
Cucumber beetles feed on leaves, blossoms, and stems of a variety of plants; in agricultural areas, both adults and larvae are serious pests. Cucumber beetles also are carriers of bacteria that cause a disease known as bacterial wilt, which causes plants to wilt and eventually die._^<g_
Sunflowers have a fibrous root system; stout, rough stems; and blossoms composed of many flowers: bright yellow ray flowers and numerous small disk flowers. Like other flowering plants that grow in grasslands, sunflowers are important food sources for a variety of animals._^<g_
Purple coneflowers bloom in late summer and autumn. Their brightly colored petals attract insects such as bees. As the insects fly from one flower to another they carry pollen, thereby enabling the coneflowers to reproduce. _^<g_
_^<n__^<b_Definition:_^>b_ temperate habitat in which grasses are the dominant vegetation and trees are lacking or rare_^<n__^<b_Geographic region:_^>b_ North America (prairies and plains), South America (pampas), Eurasia (steppe), South Africa (veldt)_^<n__^<b_Terrain:_^>b_ flat to rolling_^<n__^<b_Climate:_^>b_ distinct wet and dry seasons; long droughts are common_^<n__^<b_Precipitation:_^>b_ 10 to 30 inches per year_^<n__^<b_Average annual temperatures:_^>b_ vary depending on location; typically warm in summer, cold in winter_^<n__^<b_Soil:_^>b_ highly fertile (rich in nutrients) and deep_^<n__^<b_Dominant vegetation:_^>b_ grasses_^<n__^<g_
The killdeer's diet includes earthworms, snails, insects, seeds, and grain. It builds its nest on the ground. If an intruder approaches, the setting bird sneaks away, feigning a broken wing and calling "kill-dee, kill-dee," thereby diverting the predator's attention from the eggs._^<g_
Red-tailed hawks are large birds of prey that are at home in many kinds of habitats. They hunt while soaring or hovering in the air, and while sitting on a perch, using their excellent eyesight to spot mice, gophers, prairie dogs, rabbits, and other prey. _^<g_
Coyotes feed primarily on small mammals, birds, and--particularly in winter--carrion of large game animals. They also prey on deer, antelope, and domestic animals, hunting in pairs or bigger groups to take down the large animals. A coyote's howl seems to be a means of identifying its location to other members of the species._^<g_
Prairie dogs are short-legged, burrowing squirrels that feed mainly on grasses. Their homes, built 10 to 16 feet underground, provide refuge against hawks, eagles, and other large predators. However, the prairie dog's prime predator, the black-footed ferret, hunts it in its burrow._^<g_
Bison are grazers, feeding on a variety of grasses. Adult females and their offspring tend to gather in herds of 50 or more, while adult males are either solitary or live in small, all-male herds. During mating seasons, however, the males join the female herds and fight for a potential mate by ramming heads with their rivals._^<g_
Prairie rattlesnakes, active mainly during the day, feed on rodents and other warm-blooded animals. In late autumn, those that live in areas with cold winters gather in caves, coiling around one another and hibernating until spring._^<g_
Pocket mice have external fur-lined cheek pouches that they stuff with seeds and greens--their principal foods--to eat or store in their burrows. They are preyed on by numerous secondary consumers, including snakes, coyotes, and birds of prey._^<g_
The thirteen-lined ground squirrel, resplendent in a decorative coat, is mainly a grass eater, though it also eats birds' eggs and insects such as grasshoppers. Active during the day, it is a shy animal that hurries back to its burrow at the first sign of danger. But even in its burrow it isn't safe from predators such as snakes._^<g_
_^<n__^<b_Galaxy:_^>b_ Milky Way_^<n__^<b_Diameter:_^>b_ 3.7 billion miles_^<n__^<b_Number of stars:_^>b_ 1_^<n__^<b_Number of Planets:_^>b_ 9_^<n__^<b_Number of known comets:_^>b_ 1,000 _^<n__^<b_Number of orbit-chartered asteroids:_^>b_ 1,600 (thousands more observed)_^<n__^<b_Number of known satellites:_^>b_ 65_^<n__^<g_
_^<n__^<b_IMPORTANT ASTEROIDS_^>b__^<n__^<b_Ceres:_^>b_ The largest and first discovered asteroid, found in 1801 by Giuseppe Piazzi. It has a 593-mile diameter._^<n__^<b_Juno:_^>b_ One of the largest asteroids, discovered in 1804 by Karl Ludwig Harding. It has a diameter of 118 miles._^<n__^<b_Vesta:_^>b_ The only asteroid visible to the unaided eye, discovered in 1807 by Heinrich W. M. Olbers. It has a diameter of 336 miles._^<n__^<b_Eros:_^>b_ Used by early astronomers to determine Earth's average distance from the Sun. It was discovered in 1898 by Carl Gustav Witt._^<n__^<b_Hidalgo:_^>b_ Has longest elliptical orbit and furthest aphelion point from the Sun. It was discovered in Mexico in 1924 by German astronomers._^<n__^<b_Amor:_^>b_ Approaches within 10 million miles of Earth. It was discovered in 1932._^<n__^<b_Apollo:_^>b_ Passes within orbits of Earth and Venus. It was discovered in 1932 by Reinmuth._^<n__^<b_Hermes:_^>b_ Came within 437,000 miles of Earth in 1937. It was discovered in 1937 by Reinmuth._^<n__^<g_
_^<n__^<b_IMPORTANT NORTHERN HEMISPHERE ANNUAL METEOR SHOWERS_^>b__^<n__^<b_Quadrantids:_^>b_ Peak activity occurs on January 3, radiating within the Bootes constellation._^<n__^<b_Alpha Aurigids:_^>b_ Peak activity occurs on February 8, radiating within the Auriga constellation._^<n__^<b_Virginids:_^>b_ Peak activity occurs on March 20, radiating within the Virgo constellation. _^<n__^<b_Lyrids:_^>b_ Peak activity occurs on April 21, radiating within the Lyra constellation._^<n__^<b_Eta Aquarids:_^>b_ Peak activity occurs on May 4, radiating within the Aquarius constellation._^<n__^<b_Ophiuchids:_^>b_ Peak activity occurs on June 20, radiating within the Ophiuchus constellation._^<n__^<b_Delta Aquarids:_^>b_ Peak activity occurs on July 29, radiating within the Aquarius constellation._^<n__^<b_Perseids:_^>b_ Peak activity occurs on August 12, radiating within the Perseus constellation._^<n__^<b_Kappa Cygnids:_^>b_ Peak activity occurs on August 20, radiating within the Cygnus constellation._^<n__^<b_Alpha Aurigids:_^>b_ Peak activity occurs on September 22, radiating within the Auriga constellation._^<n__^<b_Draconids:_^>b_ Peak activity occurs on October 9, radiating within the Draco constellation._^<n__^<b_Orionids:_^>b_ Peak activity occurs on October 21, radiating within the Orion constellation._^<n__^<b_Taurids:_^>b_ Peak activity occurs on November 1, radiating within the Taurus constellation._^<n__^<b_Leonids:_^>b_ Peak activity occurs on November 17, radiating within the Leo constellation._^<n__^<b_Geminids:_^>b_ Peak activity occurs on December 13, radiating within the Gemini constellation._^<n__^<b_Ursids:_^>b_ Peak activity occurs on December 22, radiating within the Ursa Major constellation._^<n__^<g_
_^<n__^<b_IMPORTANT DATES IN THE STUDY OF COMETS_^>b__^<n__^<b_16th Century:_^>b_ Tycho Brahe determines that comets are not atmospheric phenomena, considerably farther away from the Earth than the Moon._^<n__^<b_17th Century:_^>b_ Sir Isaac Newton determines that the comet of December 1680 followed a very elongated, parabolic orbit._^<n__^<b_17th Century:_^>b_ Edmond Halley finds that the orbits of the comets of 1531, 1607, and 1682 are almost identical, and concludes that they were a single comet, and he correctly predicted its return in 1758._^<n__^<b_1908:_^>b_ A tremendous blast occurs in the Tunguska region of Russia. Some scientists speculate that it was caused by a comet impact._^<n__^<b_1983:_^>b_ Comet IRAS- Araki-Alcock, comes within 2.9 million miles of Earth--the closest known comet approach in more than 200 years._^<n__^<b_1986:_^>b_ Halley's comet makes it's most recent pass of Earth._^<n__^<b_1997:_^>b_ Newly-discovered comet Hale-Bopp comes within 9 million miles of Earth._^<n__^<g_
_^<b_Tables_^>b__^<n__^<a!B43592_Characteristics of Planets_^>a__^<n__^<a!B37865_Surface Escape Velocity, by Planet _^>a__^<n__^<g_
_^<b_Table_^>b__^<n__^<a!B40707_Meteor Showers, Important Annual in the Northern Hemisphere_^>a__^<n__^<g_
_^<b_Picture_^>b__^<n__^<a!P39034_Earth_^>a__^<n__^<g__^<b_Tables_^>b__^<n__^<a!B43592_Planets, Characteristics of _^>a__^<n__^<a!B43468_Satellites in Circular Earth Orbit, Data on _^>a__^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P49353_Jupiter's south pole viewed from Voyager 1_^>a__^<n__^<a!P39042_Jupiter view from Voyager_^>a__^<n__^<g__^<b_Table_^>b__^<n__^<a!B43592_Planets, Characteristics of _^>a__^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P49088_Mariner 9_^>a__^<n__^<a!P49356_Mars landscape viewed from Viking_^>a__^<n__^<a!P39044_Mars view from Viking_^>a__^<n__^<a!P39534_Viking 1 on Mars_^>a__^<n__^<g__^<b_Table_^>b__^<n__^<a!B40571_Mars, Characteristics of _^>a__^<n__^<g_
_^<b_Picture_^>b__^<n__^<a!P49355_Mercury from Mariner 10_^>a__^<n__^<g__^<b_Table_^>b__^<n__^<a!B40680_Mercury, Characteristics of _^>a__^<n__^<g_
_^<b_Picture_^>b__^<n__^<a!P49880_Meteor showers_^>a__^<n__^<g__^<b_Table_^>b__^<n__^<a!B40707_Meteor Showers, Important Annual in the Northern Hemisphere_^>a__^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P39055_Neptune view from Voyager_^>a__^<n__^<a!P49333_Neptune view from Voyager 2_^>a__^<n__^<g__^<b_Table_^>b__^<n__^<a!B43592_Planets, Characteristics of_^>a__^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P49342_Mimas, Saturn satellite_^>a__^<n__^<a!P39062_Saturn view from Voyager_^>a__^<n__^<a!P49343_Saturn's rings viewed from Voyager 1_^>a__^<n__^<a!P49341_Saturn's satellite Titan from Voyager 1_^>a__^<n__^<a!P39536_Voyager/Saturn approaches Saturn_^>a__^<n__^<g__^<b_Table_^>b__^<n__^<a!B43490_Saturn, Rings and Satellites of _^>a__^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P39066_Uranus view from Voyager_^>a__^<n__^<a!P49352_Uranus view from Voyager 2_^>a__^<n__^<g__^<b_Table_^>b__^<n__^<a!B43592_Planets, Characteristics of_^>a__^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P39521_Pioneer spacecraft_^>a__^<n__^<a!P39068_Venus_^>a__^<n__^<a!P49349_Venus from Magellan_^>a__^<n__^<a!P49351_Venus landscape_^>a__^<n__^<g__^<b_Tables_^>b__^<n__^<a!B43592_Planets, Characteristics of _^>a__^<n__^<a!B44054_Soviet Venus Probes _^>a__^<n__^<g_
_^<n__^<a!T7901_conjunction_^>a__^<n__^<a!T8944_Danjon, Andre Louis_^>a__^<n__^<a!T21673_Mercury (planet)_^>a__^<n__^<a!T21062_Mariner_^>a__^<n__^<a!T21773_meteorite craters_^>a__^<n__^<a!T30357_solar system_^>a__^<n__^<a!T32864_transit_^>a__^<n__^<g_
_^<n__^<a!T183_achondrite_^>a__^<n__^<a!T6969_chondrite_^>a__^<n__^<a!T21771_meteor and meteorite_^>a__^<n__^<a!T21772_Meteor Crater_^>a__^<n__^<a!T21773_meteorite craters_^>a__^<n__^<a!T30357_solar system_^>a__^<n__^<a!T33159_Tunguska fireball_^>a__^<n__^<g_
_^<n__^<a!T254_Adams, John Couch_^>a__^<n__^<a!T554_airglow_^>a__^<n__^<a!T19533_Leverrier, Urbain Jean Joseph_^>a__^<n__^<a!T23384_Neptune_^>a__^<n__^<a!T25961_Planet X_^>a__^<n__^<a!T30357_solar system_^>a__^<n__^<a!T33009_Triton (astronomy)_^>a__^<n__^<g_
_^<n__^<a!T554_airglow_^>a__^<n__^<a!T10800_electroglow_^>a__^<n__^<a!T15667_Herschel, Sir William_^>a__^<n__^<a!T22122_Miranda_^>a__^<n__^<a!T25961_Planet X_^>a__^<n__^<a!T30357_solar system_^>a__^<n__^<a!T33538_Uranus (astronomy)_^>a__^<n__^<g_
_^<n__^<a!T2072_astrogeology_^>a__^<n__^<a!T7901_conjunction_^>a__^<n__^<a!T8944_Danjon, Andre Louis_^>a__^<n__^<a!T21062_Mariner_^>a__^<n__^<a!T21773_meteorite craters_^>a__^<n__^<a!T30357_solar system_^>a__^<n__^<a!T32864_transit_^>a__^<n__^<a!T33839_Venera_^>a__^<n__^<a!T33854_Venus_^>a__^<n__^<g_
Lister's keyhole limpet is named for the hole in the center of its shell. It lives on the undersides of rocks, grazing on microscopic algae. When the water recedes, the limpet uses strong muscles to pull its shell tight against the rock, thereby keeping its soft body from drying out in the open air. _^<g_
The Atlantic plate limpet has an oval grayish shell decorated with brown streaks and bars. The animal clings to rocks in tide pools, grazing on microscopic algae. When the water recedes, the limpet uses strong muscles to pull its shell tight against the rock, thereby keeping its soft body from drying out in the open air. _^<g_
The shell of the rough keyhole limpet has a coarse exterior and a hole in the center. This animal lives on rocks and grazes on microscopic algae. When the water recedes, the limpet uses strong muscles to pull its shell tight against the rock, thereby keeping its soft body from drying out in the open air. _^<g_
Fiddler crabs are active during the day, and hide in their burrows at night. As the tide recedes, the crabs run over the rocks, looking for food. A male fiddler crab has an enormous front claw that it waves about when fighting other males and trying to attract a female. _^<g_
The soft body of the black tegula snail is protected by a whorled shell. The animal clings to rocks._^<g_
Ceramiums are red algae with a branching body, or thallus. They usually are red in color, due to the pigment phycoerythrin, but bleaching turns some greenish, yellowish, or even white. When covered with water, ceramiums have a bushy appearance; out of water they collapse in a limp mass._^<g_
Barnacles are common in the upper intertidal zone. When they are covered with water, they open their shells and use hairs on their feet to catch tiny animals and algae as they drift by. When the tide recedes, barnacles close their shells to prevent drying._^<g_
Codium is a green algae with a much-branched body. The branches are thick and ropelike and up to 3 feet long. Growth is most active during the warm summer months. In some places, codium grows so densely, that it suffocates mollusks and other invertebrates._^<g_
Rockweed, a brown algae, is common in the intertidal zone, often covering acres with a dense mass of slippery fronds. A rootlike holdfast attaches each organism to a rock; the fronds are flattened and branch repeatedly. Swollen air-filled bladders are scattered along the branches; these enable the fronds to float on the water's surface._^<g_
The common sea star is a predator that is particularly fond of mussels. It uses the tube feet on the underside of its arms to pry open a mussel's shell. If the sea star loses an arm in an accident or to a predator, it can regenerate the missing part. _^<g_
Blue mussels live in the mid-intertidal zone; they are unable to withstand the dry conditions in the upper intertidal zone. They cling to rocks by means of extremely tough filaments called byssus threads. They feed on microscopic organisms, and in turn are eaten by starfish._^<g_
Ruddy turnstones use their pointed bill to search for mollusks, worms, eggs, and other food. With the bill they can lift stones, dig holes in wet sand, and rummage through a pile of seaweed. When a ruddy turnstone senses danger, it warns other birds with a loud alarm cry. _^<g_
Irish moss is a red algae that often grows in dense masses. It is harvested by people and used as a source of carrageenin, a gelatinizing substance that has many commercial uses._^<g_
Sea anemones have stinging cells that stun small prey, which are then pulled into the mouth at the top center of the round body. When the tide recedes, sea anemones contract, pulling tentacles into the mouth and closing the mouth. This prevents the animals from drying out at low tide. _^<g_
Semipalmated plovers eat small mollusks and crustaceans, marine worms, and various insects, including larvae of the salt-marsh mosquito. They are swift runners, good swimmers, and strong flyers. At sunset, flocks gather over the high-tide mark to sleep._^<g_
Razor clams live on the ocean floor in quiet coastal waters. They move along the bottom by contracting the two valves of the shell and using their large muscular foot. When a razor clam dies or is eaten by a predator, its long, thin shell may be washed up onto beaches._^<g_
When covered with water, the tentacles of the green anemone move about, making this animal look like a small blossom. Like other sea anemones, the green anemone has a suckerlike base that firmly attaches it to rocks and other solid substrates. _^<g_
Dasya, a genus of red algae, gets its name from the Greek word meaning "hairy." Fronds are long and sinuous, and covered with short, hairlike branches. This is a comparatively fragile algae; its fronds are often torn into fragments by the waves._^<g_
Sponges are common invertebrates in the low intertidal zone, living in moist, shady areas. Water enters a sponge's body through tiny pores in the outer covering. It passes into a central cavity, where special cells remove microscopic organisms and food particles. The water then leaves through a large opening at the top of the animal. _^<g_
Sea squirts are small invertebrates that live in the low intertidal zone, in moist, shady places beneath overhanging rocks. The posterior end of a sea squirt's body is attached to an object or buried in mud or sand. The anterior end has two siphons. Water carrying food enters through one siphon. Waste water leaves through the other siphon._^<g_
Hermit crabs have soft bodies that fit perfectly into empty snail shells. As a hermit crab outgrows one shell, it finds another, larger shell in which to live. Moving from one shell to another is a dangerous procedure, leaving the crab especially vulnerable to predators._^<g_
Sea grapes are sea squirts that live in dense clusters that look like bunches of grapes. Common in shallow water on stones, wharf piles, and other substrates, they feed on tiny particles that they filter from the water. The surface of their bodies often is encrusted with debris--and sometimes with colonies of other sea squirts._^<g_
A rock crab uses its legs, which are densely covered with stiff hairs, to remove small food particles from the water. The particles are passed forward from one leg to the next until they reach the mouth. The crab depends on its eyes and sensory organs on its long, slender antennae to gather information about the surroundings. _^<g_
The calico scallop is named for its colorful shell, which has about 20 ribs. It is highly motile. To move through the water, it quickly opens and closes its valves several times; water is forcefully thrust out in one direction, propelling the scallop in the opposite direction._^<g_
Sand dollars have a hard, circular shell that is densely covered with very short, movable spines. They live partly buried in sand. The mouth is on the underside of the shell, surrounded by five strong teeth, which are used to tear algae--the main food of sand dollars._^<g_
Like other sea stars, the blood star depends on the tiny tube feet on the bottom of its arms to follow and overtake prey. It wraps its arms around the prey, pushes its stomach out of its mouth, and digests the prey outside its body. Then it sucks its full stomach back inside. _^<g_
Laminaria is a genus of large kelp that are characterized by broad, leathery fronds, flexible stalks, and massive holdfasts that prevent the organisms from being ripped from rocks by crashing waves. Laminaria grow in the low intertidal zone._^<g_
A fanworm is a marine worm that has a feather duster-like fan of tentacles. Bits of plankton cling to tiny hairs on the tentacles. With a constant brushing motion, the hairs sweep food into the worm's mouth. At the first sign of danger, the worm quickly withdraws its tentacles, pulling them inside the tube in which it lives._^<g_
_^<n__^<b_Definition:_^>b_ area between the high and low tidemarks of marine coasts_^<n__^<b_Geographic region:_^>b_ worldwide_^<n__^<b_Substrate:_^>b_ varies_^<n__^<b_Zones:_^>b_ typically, four: splash zone (supralittoral fringe), upper intertidal zone (upper mid-littoral), mid-intertidal zone (lower mid-littoral), and low intertidal zone (infralittoral fringe)_^<n__^<b_Water temperature:_^>b_ varies, depending on geographic location, ocean currents, etc._^<n__^<b_Dominant vegetation:_^>b_ algae_^<n__^<g_
_^<n__^<a!T3049_beach and coast_^>a__^<n__^<a!T3802_bivalve_^>a__^<n__^<a!T14786_habitat_^>a__^<n__^<a!T17049_intertidal life_^>a__^<n__^<a!T25783_piddock_^>a__^<n__^<a!T33365_Ulothrix_^>a__^<n__^<g_
The scarlet macaw, one of the largest and most brightly colored of the world's parrots, feeds on seeds, fruits, nuts, and other plant matter. Mating for life, it makes its nest in tree hollows high above the jungle floor._^<g_
Named for its long, spiderlike limbs, the spider monkey is completely arboreal. It uses its hands to swing from branch to branch. Its tail, which is longer than the body, can be used to pick up things. Spider monkeys associate in small troops. Plant matter and insects are the mainstays of their diet._^<g_
The tapir spends a lot of time up to its nose in water, thus avoiding biting insects and predators such as jaguars. It browses on grasses and other plants found in shallow water and on riverbanks. It is very territorial and quick to fight other tapirs that trespass on its territory._^<g_
The two-toed sloth spends most of its life hanging upside down from the branch of a tree, even mating and giving birth in this position. It rests during the day and moves slowly at night, feeding on fruits, leaves, and other plant matter. If attacked by a jaguar or other enemy, it uses its strong claws to defend itself._^<g_
The emerald tree snake moves easily through jungle treetops, using its strong tail to steady itself on slippery branches and trunks. When it locates a lizard or bird--its main prey--it sinks its fangs into the victim, then coils around the animal and squeezes, killing by suffocation. It swallows the animal whole._^<g_
Spoonbills are large wading birds with a long, flattened bill that is widened and rounded at the tip, forming a spoon that the birds use to sift and strain for small crustaceans and other food. Gregarious birds, they generally feed in flocks and nest in colonies._^<g_
The Amazon turtle, like other cold-blooded animals, needs the Sun's heat to warm its body into action. _^<g_
Growing in quiet, sunlit waters, Victoria water lilies produce leaves that grow up to 6 feet in diameter. The leaves are strong enough to support even medium-sized creatures eager to sunbathe or survey the surroundings. _^<g_
Jaguars are the largest carnivores in the South American jungle, preying on peccaries, capybaras, tapirs, turtles, fish, and even crocodiles. Powerful and swift on land, they are also excellent climbers and swimmers. Solitary animals, they fiercely defend territory and recently killed prey._^<g_
Male blue morpho butterflies, with their wings of iridescent blue, are among the world's most beautiful creatures. In contrast, the females are brownish. Morpho butterflies spend most of their time in the jungle's tallest trees, though they occasionally descend to the ground to drink from puddles._^<g_
Pacas are large, strong rodents that hunt at night, feeding on fruits, leaves, roots, and other plant matter. They move silently through the underbrush but when disturbed will race up trees, jump into water, or disappear into a hole. If cornered, they bite their attackers._^<g_
Squirrel monkeys live in troops of 10 to 100 individuals, with complex rules of social behavior. They spend most of their time in the upper branches of tall trees, where they feed mainly on fruits but also eat insects and spiders, which they catch in the palm of the hand._^<g_
The scarlet ibis uses its long, slim, down-curving bill to pick up crustaceans, insects, and small fish. The birds live in colonies, often on islands with mangrove trees and other marshland plants. Within the colony, each mated pair defends a small territory, where it builds an intricate basket-shaped nest._^<g_
The Brazilian rhinoceros beetle is named after the dramatic horn on its head. Males use the horn to fight with one another. The larvae feed on decaying matter while the adults drink tree sap and the juice of soft fruits. _^<g_
The keel-billed toucan has a large, strong beak that isn't heavy because it is honeycombed with air chambers. It eats fruits and berries, plus insects, small reptiles, and the eggs and young of other birds. It is a skilled flyer and climber. It is a gregarious bird, roosting communally and communicating in hoarse squawks._^<g_
Cattleya orchids are epiphytes that grow on the trunks of jungle trees. They have a short stem; leathery, lily-like leaves; and large showy flowers. The flowers attract insects, which carry pollen from one flower to another. _^<g_
Several species of South American frogs produce potent poisons that are used by Indians as deadly additions to arrowheads, hence the name. Arrow poison frogs are brightly colored, serving to warn would-be predators to stay away._^<g_
Giant otters live in and along slow-moving rivers, building their dens in the riverbank or under tree roots. Superb swimmers, they use their webbed feet, streamlined body, and rudderlike tail to propel themselves swiftly through the water. Their diet consists mainly of fish._^<g_
The discus--named for its round, disk-shaped body--lives in weedy, slow-moving jungle streams, hiding and hunting among fallen branches and underwater plants. It feeds on worms, larval and adult insects, and other invertebrates. _^<g_
The giant arapaima is a massive fish that weighs up to 200 pounds. It has huge eyes, a bony-plated head, and a large swim bladder that can function as a lung. Its preferred diet is fish, but it also eats crustaceans and reptiles._^<g_
Piranhas benefit their habitat by feeding mainly on diseased and injured fish and other animals, thereby reducing the likelihood of epidemics among river organisms. Spilled blood from one piranha's efforts attracts other piranhas, and they swarm until the prey is completely eaten._^<g_
_^<n__^<b_Definition:_^>b_ "jungle" generally refers to a tropical, highly stratified rain forest in which the tallest trees form a dense canopy_^<n__^<b_Geographic region:_^>b_ tropics_^<n__^<b_Terrain:_^>b_ varied_^<n__^<b_Climate:_^>b_ tropical, damp, humid_^<n__^<b_Precipitation:_^>b_ 70 to 200 inches per year; usually well distributed throughout the year_^<n__^<b_Average annual temperatures:_^>b_ 70-80 degrees F_^<n__^<b_Soil:_^>b_ commonly poor, with low level of nutrients that is continually renewed by the vegetation_^<n__^<b_Dominant vegetation:_^>b_ tall, broad-leaved evergreen trees_^<n__^<g_
_^<n__^<a!T12450_forests and forestry_^>a__^<n__^<a!T14786_habitat_^>a__^<n__^<a!T17897_jungle and rain forest_^>a__^<n__^<g_
Alpine choughs are crowlike birds that are seen on mountains up to elevations of 18,000 feet. They are skilled gliders. Their diet consists largely of insects, which they catch with their sharp, long bills. In summer and fall, they fly down into valleys to feast on cherries and other fruits._^<g_
Golden eagles are large birds of prey, with a wingspan of about 7 feet. They fly low over open areas, hunting small and medium-sized mammals and birds. Sometimes they harass other birds to give up their prey. They also feed on carrion. _^<g_
The snow leopard's high-set eyes enable it to peer over the edge of rocks with the least possible exposure of itself. Strong and agile, it is capable of bringing down wild sheep, goats, and other large animals. During the summer, snow leopards prowl at elevations up to 19,000 feet. As winter approaches, they move down the mountain._^<g_
Bharal are also called blue sheep because of the bluish color of their coat. They live on slopes close to cliffs, grazing on grasses, herbs, and lichens. Their main enemies are snow leopards. Males have long horns that curve backwards; females have tiny horns._^<g_
Pikas are small, pudgy relatives of rabbits and hares, with large ears and short legs. They feed on grasses and other plants, storing some of this food in their burrows for the winter. If a pika spots a predator, it emits a high-pitched warning cry, then dives for its burrow._^<g_
Gentians are perennials with deep blue flowers. Nectar secreted by the flowers attracts bees, which then carry pollen from one flower to another._^<g_
Accentors, also known as hedge sparrows, are predominantly earth-dwellers; their brown and gray plumage blends with the bare rocks and open soil of their mountain homes. They build their nests on low bushes or on the ground, sometimes among rocks. They feed on insects and other invertebrates, as well as berries and seeds._^<g_
The wall creeper is adept at climbing steep rock faces in search of ants, spiders, and other prey. An exceptionally long claw on each hind toe helps the bird grasp even minute projections on rocks. Wall creepers nest among rocks, deep in a narrow crevice or hole._^<g_
Alpine voles are small rodents with stout bodies and short, rounded ears. They live in burrows or small cavelike spaces among the rocks. Their vegetarian diet consists mainly of grasses herbs, and seeds. They are preyed on by numerous mammals and birds. _^<g_
_^<n__^<b_Definition:_^>b_ a biome on a mountain, elevated above the surrounding terrain, with thinner air, cooler temperatures, and a shorter growing season; term frequently refers to the Alpine tundra biome above the timberline_^<n__^<b_Geographic region:_^>b_ worldwide_^<n__^<b_Terrain:_^>b_ steep, rocky_^<n__^<b_Climate:_^>b_ varies; often distinctly different on opposite sides of a mountain_^<n__^<b_Precipitation:_^>b_ varies; higher on upwind side than downwind side_^<n__^<b_Average annual temperatures:_^>b_ varies, depending on geographic location and elevation; upwind side tends to have a more even temperature range than downwind side; temperature decreases about 1 degree F for every 330-foot rise in elevation_^<n__^<b_Soil:_^>b_ generally thin and not very fertile_^<n__^<b_Dominant vegetation:_^>b_ above timberline, perennial herbs and other small plants that hug the ground_^<n__^<g_
African fish eagles live near lakes, swamps, and rivers. They use their excellent eyesight to spot fish while perched on trees or flying through the air. They either snatch fish from the water or dive into the water in pursuit of the prey. Afterwards, they will perch on sunny treetops to dry their feathers._^<g_
Termites are common insects on the African savanna. They live in colonies that may have a population of several million individuals, building dark, warm nests that rise like miniature mountains._^<g_
Elephants are gregarious animals, often associating in herds of 25 to 30. An elephant spends most of its time collecting food. To maintain its size, it must eat hundreds of pounds of plant material every day._^<g_
Weaver birds have heavy, conical bills, which they use to crush the seeds of grasses and other plants. They are highly sociable; dozens may hang their swinging nests from a single tree._^<g_
Acacias - called thorns in eastern Africa - are common trees on the savanna. They can tolerate long periods of drought and their thorns protect them from most browsers. For giraffes, however, acacia leaves are a favorite food. The trees have an umbrella shape, and many animals spend the hot hours of midday resting in their shade. _^<g_
Giraffes live alone or in small groups. They are browsers, feeding mainly on the leaves and new shoots of trees and tall bushes. When this supply is spent, they feed on low bushes and shrubs by spreading their legs and kneeling down, a position that leaves them vulnerable to attacks by lions._^<g_
Wildebeests, also called gnus, usually live in small herds, but may congregate in herds of up to 1,000 animals during migration or on a new flush of grass. They eat grasses and the leaves of small bushes. They are swift runners, escaping lions, leopards, hyenas, and other predators by outrunning them._^<g_
The black rhinoceros eats leaves, shoots, fruits, and roots. It stays close to a waterhole, or wallow, taking a daily mud bath to control body temperature and gain relief from biting insects. Its eyesight is poor but its hearing and sense of smell are highly developed._^<g_
Spotted (laughing) hyenas have strong jaws that enable them to crack and crush the bones of carcasses. They also attack young antelopes and other mammals, and eat fruit. Gregarious, nocturnal creatures, they live and hunt in groups. Their young are raised in underground burrows._^<g_
The hammerkop, or hammerhead, is a wading bird with a heavy bill that looks like the head of a hammer. It is most active at dusk, when it wades through streams and uses its bill to catch fish, frogs, crustaceans, and water bugs. It builds huge domed nests, usually in the low fork of a tree, often over water._^<g_
The kudu is an extremely wary antelope. It hides during the day, coming out to feed in the evening and early morning. It eats grasses and other plant matter. Agile and swift, kudus quickly flee at the first sign of predators, warning each other of the danger by barking loudly._^<g_
Impalas escape lions and other predators by zigzagging and leaping as they run. They feed on grasses and on the leaves of bushes. In the dry season, impalas gather near water in herds of up to 100 animals. During the rainy season, females and young form herds led by a single adult male. Other males form their own groups._^<g_
The hippopotamus spends most of its day sleeping on river shores or lying in the water with only its eyes and nostrils above the surface. Its skin produces an oily liquid that protects against the Sun's drying rays and the effects of lengthy immersions in water. Hippos are plant eaters, feeding at night on land._^<g_
Burchell's zebra lives in herds that often include hartebeest, wildebeest, and other gregarious mammals. They graze mostly in the early morning and the evening, going at intervals to waterholes or streams to drink._^<g_
The white-faced whistling duck is a social creature, living in flocks that may number in the hundreds. It lives in a variety of freshwater habitats, though it prefers areas with mud or sandbars for roosting. It obtains most of its food by diving, and feeds on aquatic insects, mollusks, crustaceans, and aquatic plant seeds._^<g_
Malachite kingfishers are swift flyers that feed on fish as well as dragonflies and other insects found in or near water. They are most common around swamps and lakes, except during the breeding season, when they prefer rivers, making their nests in the rivers' banks._^<g_
Thomson's gazelles live in herds. They graze at dawn and dusk. During the dry season, they also eat fruits and seeds. The slightest sign of danger panics a herd, and it races off. These gazelles can outrun both lions and leopards, but they have a more difficult time escaping cheetahs. _^<g_
Lions live in groups called prides. They rest during the heat of the day and hunt at night. Favored prey include zebras, wildebeests, and other animals large enough to satisfy the hunger of the entire group. Usually, a female makes the actual kill, jumping onto the prey and killing it by biting the throat or the nape of the neck._^<g_
The electric catfish is a belligerent and voracious fish that will even fight with members of its own species. It has an electric organ just under the skin that runs from the head to the front of the tail. An adult can release a charge of up to 350 volts. It uses this ability to stun and kill prey. _^<g_
Elephantfish are long-faced freshwater fish that are active mostly at night. They maintain a weak electric field around themselves which allows them to detect nearby objects that interrupt the pattern of this field._^<g_
The dwarf elephantfish, like other members of the family Mormyridae, has a long, flexible snout curved into a trunk, which is used to probe in the mud for food. Also like other mormyrids, it has modified muscles near its tail that produce mild electric shocks. The electricity appears to be used to locate food._^<g_
Naked mole rats are hairless except for a few whiskers. They live in underground colonies of about 30 animals, seldom coming above ground. They dig elaborate burrows; soil tossed out of the hole forms a high mound near the entrance. They eat roots and tubers._^<g_
African lungfish have lungs as well as gills, which permits them to rise to the surface for a breath of air. They are pugnacious creatures that are quick to fight, even with one another. During the dry season they burrow in the mud and form a thick mucous cocoon, which becomes encapsulated in a shell of dry mud._^<g_
Agama lizards live in a variety of habitats over much of Africa. Strongly built, with long legs and sharp eyesight, these reptiles are great killers of insects. Though they enjoy basking in the sun, they seek shade during the hottest times of the day. Their color changes as they move from sun to shade. _^<g_
_^<n__^<b_Definition:_^>b_ tropical grassland with scattered shrubs and trees_^<n__^<b_Geographic region:_^>b_ tropics around the world_^<n__^<b_Terrain:_^>b_ generally flat_^<n__^<b_Climate:_^>b_ tropical_^<n__^<b_Precipitation:_^>b_ 4 to 16 inches a year; distinct wet and dry seasons; long droughts are common_^<n__^<b_Average annual temperatures:_^>b_ warm or hot all year round_^<n__^<b_Soil:_^>b_ generally thin, and not very fertile_^<n__^<b_Dominant vegetation:_^>b_ tall grasses_^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P36333_Giraffe_^>a__^<n__^<a!P36335_Hippopotamus_^>a__^<n__^<a!T-1_Hyena with its prey_^>a__^<n__^<a!P49911_Kudu_^>a__^<n__^<a!P47296_Queen Elizabeth National Park, Uganda_^>a__^<n__^<a!P40864_Termite_^>a__^<n__^<a!P36207_Wildebeest_^>a__^<n__^<g_
The tall, stately demoiselle crane lives and travels in flocks. It summers on steppes in eastern Europe and throughout central Asia, then flies to warmer climes for the winter. Cranes perform dramatic courtship dances, with both members of a pair leaping high into the air, then bowing before one another._^<g_
The Bactrian (two-humped) camel feeds on grasses and other vegetation. When food and water are not readily available, it depends on stored fats in its hump. Its thick coat provides insulation. Bactrian camels can run for several hours without stopping, and can outrace horses over long distances._^<g_
Asian wild asses live in herds. They eat grasses, herbs, and bark, and can survive long periods without water. The herd constantly watches for wolves and other predators, and flees at the first sign of danger._^<g_
Saigas are small antelopes with a large head and large nostrils. In winter, the nostrils warm the icy air before it reaches the animal's lungs. In summer, the nostrils filter out dust raised by herds as they run around the dry ground. Saigas are among the most important grazers on the steppe, feeding mainly on herbs and lichens._^<g_
Mixed among the grasses in moister portions of the steppe are peonies and other herbaceous plants with showy flowers. _^<g_
Blue grass has a dense fibrous root system that helps it survive during periods of drought. It and other grasses are the primary source of food for animals of the steppes. Some animals can digest the silica-rich leaves of grasses. Other animals eat grass roots or seeds. And still other animals eat the plant-eaters._^<g_
Marmots eat grasses and other plant matter. They hibernate through the winter, huddled together in underground dens. In spring, when they first scamper from the dens, they seek a sunny rock on which to warm their bodies._^<g_
Rose-colored starlings feed mainly on fruits and seeds, though they also catch insects. Small birds, they are adept at both walking and flying. They move in bands and live and breed in large groups; a nesting colony may contain thousands of breeding pairs. _^<g_
Wild tulips and other hardy wildflowers, interspersed among the grasses that dominate steppes, burst into colorful bloom in the spring. A tulip plant has a large underground bulb; this specialized structure serves primarily for food storage but also for reproduction._^<g_
The burrowing of the suslik, a large short-tailed ground squirrel of eastern Europe and northern Asia, contributes to soil development and fertility and to biological activity in soils._^<g_
Steppe lemmings are small rodents that feed on lichens, mosses, and grasses. Their population is cyclical, depending on available food. When their populations soar, many are eaten by birds of prey and other predators._^<g_
Black-bellied hamsters forage at night, stuffing food into their cheek pouches and storing it in their underground homes. Seeds and other plant matter make up the bulk of their diet, but they also eat meat. In autumn, the hamsters prepare to hibernate. They cram food into the cheek pouches, then curl up for a winter's sleep._^<g_
Lesser mole rats are rodents that live where the soil is good for burrowing. Their main sense organ is the flattened snout, which has a row of bristles on either side. Burrowing is done with sharp incisors, and the snout packs loose soil into the walls. Mole rats eat roots and bulbs and may come out at night for seeds and grass._^<g_
_^<n__^<b_Definition:_^>b_ arid, temperate grassland, often flat and devoid of trees_^<n__^<b_Geographic region:_^>b_ the term general refers to grasslands of central Eurasia_^<n__^<b_Terrain:_^>b_ more or less level_^<n__^<b_Climate:_^>b_ temperate_^<n__^<b_Precipitation:_^>b_ 12 to 16 inches a year; seasonal and variable_^<n__^<b_Average annual temperatures:_^>b_ hot in summer, cold in winter_^<n__^<b_Soil:_^>b_ fertile, well-drained_^<n__^<b_Dominant vegetation:_^>b_ short grasses_^<n__^<g_
_^<n__^<b_Definition:_^>b_ a marshy-plain habitat north of the tree line characterized by permafrost and the alternate freezing and thawing of the topsoil_^<n__^<b_Geographic region:_^>b_ north of the timberline in North America, Europe, and Asia_^<n__^<b_Terrain:_^>b_ more or less flat; surface characteristically bumpy, with low mounds_^<n__^<b_Climate:_^>b_ long, cold winters; short, cool summers_^<n__^<b_Precipitation:_^>b_ generally less than 14 inches a year_^<n__^<b_Average annual temperatures:_^>b_ generally below 32 degrees F_^<n__^<b_Soil:_^>b_ low fertility, acidic, and boggy; top layer underlain by permanently frozen soil (permafrost)_^<n__^<b_Dominant vegetation:_^>b_ lichens and grasses_^<n__^<g_
Like other hawks, Everglade kites have excellent eyesight, a hooked beak, and sharp talons. They feed exclusively on snails that live in watery marshes, hunting in early morning and late afternoon, when the snails are near the surface of the water._^<g_
The prothonotary warbler can often be found hopping about on a half-submerged log or clinging to a tree trunk, looking for beetles, spiders, and other prey, which it snaps up with its short, sharp-pointed bill._^<g_
Spanish moss is an epiphyte; it lacks roots and derives moisture and nutrients from the air. It grows in drooping masses from tree branches, particularly on cypresses and oaks. Its seeds are carried by the wind, lodging and germinating on rough tree bark._^<g_
Raccoons are omnivorous but prefer aquatic food. They fish by sitting on the edge of the water or walking through the shallows of a lake or stream. Raccoons prefer mature forests where water is readily available. After looking for food at night, they spend the day resting in their dens._^<g_
Flamingos have a large, downward-bent bill and a large fleshy tongue. They feed mainly on algae and diatoms, which they filter from the mud on the bottom of brackish and saltwater lakes and lagoons. _^<g_
Saw grass is actually a sedge, a perennial adapted to inhabiting wet soil. It has a rootlike underground stem from which arises a tuft of leaves. The leaves have harsh cutting edges, hence the name. Saw grass plays an important role in binding and stabilizing swamp soil._^<g_
Wild pine is an epiphyte, or air plant, that grows on trees, thereby getting sun on its leaves. It is not a parasite; it obtains moisture and nutrients from rainwater, debris, and minerals that leach from the host trees. The wild pine's stiff, grayish-green leaves resemble those of its relative, the pineapple._^<g_
Roseate spoonbills are wading birds recognized by the long, flattened bill that is widened and rounded at the tip, forming a spoon. The bird uses its bill to sift through watery mud for mollusks, crustaceans, and other prey. Nests are built in low trees or bushes, in rookeries with herons, ibises, and other water birds._^<g_
The alligator spends much of its time completely still, warming itself in the sun. A strongly muscled, powerful animal that is more at home in water than on land, it is at the top of various food chains in the swamp, eating any animal smaller than itself--including other alligators. _^<g_
The colorful purple gallinule favors swamps and marshes filled with pickerelweed. Its long toes help it walk on lily pads and floating vegetation. It eats seeds and small animals such as frogs and snails. It builds its nest suspended from marsh plants or in willow thickets. _^<g_
The toes of green tree frogs end in adhesive pads that enable them to cling to tree trunks. Their coloration blends into the surroundings, helping them escape the notice of predators. They feed on insects. _^<g_
Water lilies grow in quiet waters. They have large floating leaves that arise from a submerged rootstock. Flowers are usually large and often brightly colored; they too float on the surface, with their stalks reaching down to the mud below._^<g_
Painted turtles prefer shallow, quiet water. They also bask in the sun on rocks or fallen trees, sometimes in groups of a dozen or more. They eat aquatic plants, insects, worms, fish, frogs, and mollusks._^<g_
Anhingas are slender web-footed birds with very long necks that allow them to make rapid, darting stabs at prey. They eat mainly fish, such as catfish and pickerel, but also take frogs, water snakes, aquatic insects, and even young alligators._^<g_
The sunfish is a small, mottled fish that lives in quiet lakes and ponds that contain a lot of vegetation. The most familiar sunfish species, the bluegill, can reach a weight of 1.75 kg (4.75 lb) and a length of 25 cm (10 in)._^<g_
Water hyacinths float on the water's surface, their long, feathery roots trailing downward. They live in places such as ponds, quiet streams, and irrigation ditches. Their stalks of blue-violet flowers rise about a foot above the leaves. _^<g_
Manatees are grazers that are especially active at night. They have a thick upper lip with two wide lobes that hang down. In the front of the mouth are horny plates instead of incisors; these are used for harvesting and grinding underwater plants._^<g_
Dark spots on the back of a leopard frog help camouflage the animal; unless it moves, it is likely to escape the notice of a predator. Adults subsist primarily on insects. Like other amphibians, they have a thin skin and need to live in places with fairly high humidity._^<g_
The oxeye tarpon feeds primarily on other fish. It has a large mouth, with rows of fine sharp teeth covering the jaws, tongue, and roof of the mouth. _^<g_
The muskrat is awkward on land but an excellent swimmer and diver, paddling with its hind feed and using is flat, hairless tail as a rudder. It lives in a burrow or cone-shaped lodge and feeds primarily on cattails and bulrushes. _^<g_
_^<n__^<b_Definition:_^>b_ forested wetland_^<n__^<b_Geographic region:_^>b_ throughout most of world_^<n__^<b_Terrain:_^>b_ usually flat and low-lying_^<n__^<b_Climate:_^>b_ varied, depending on locale_^<n__^<b_Precipitation:_^>b_ varied_^<n__^<b_Average annual temperatures:_^>b_ varied, depending on locale_^<n__^<b_Soil:_^>b_ varied; generally high in dead organic matter_^<n__^<b_Dominant vegetation:_^>b_ flood-tolerant trees or shrubs_^<n__^<g_
_^<n__^<a!T11467_Everglades_^>a__^<n__^<a!T14786_habitat_^>a__^<n__^<a!T30006_Sirenia_^>a__^<n__^<a!T31522_swamp, marsh, and bog_^>a__^<n__^<a!T34548_water table_^>a__^<n__^<g_
Tree snails, protected by a spiral-like shell, use their broad, flat foot to creep along leaves and trunks. They use their tooth-covered radula to scrape bits of food from the plant surface._^<g_
Spicules are rapid-moving jets of gas which shoot up from the low chromosphere into the corona. Each lasts for about five minutes, and may reach a height of 10,000 miles._^<g_
Faculae are bright, irregular veinlike magnetic areas of the photosphere which surround sunspots. They are visible in white light near the edge of the Sun, and live much longer than sunspots (typically several months)._^<g_
The chromosphere is an irregular layer of gases that extends from the photosphere (visible edge of the Sun) to join with the overlying corona. The temperature gradient is reversed in the chromosphere; temperature increases with distance outward from the Sun._^<g_
The photosphere is the outer layer of the Sun. It is home to the most familiar solar phenomena, such as sunspots and prominences. Nearly all of the Sun's light and heat are emitted there._^<g_
Convective cells transfer heat in a circulatory process from hotter regions below to cooler regions above. Numerous convective cells in this region keep the gases in the outer layers well mixed._^<g_
There are two types of ray craters on Mercury's surface. The older ones are thought to be relics of the planet's creation billions of years ago. The younger ones may consist of materials blasted out by impacts against the planet. Craters have avoided erosion because of Mercury's lack of an active atmosphere. Large ray craters on Mercury have diameters of approximately 125 miles._^<g_
One of Mercury's two "hot spots" (points at which the Sun can be directly overhead when Mercury is nearest the Sun), Caloris Basin is a plain 800 miles wide. It may have been formed by impact from a projectile with asteroid dimensions._^<g_
Mercury appears to have a partially molten iron or iron-nickel core. Relatively large (75 percent of its radius), the core is presumed to be responsible for Mercury's magnetic field, which is weaker than Earth's but strong enough to disrupt the solar wind._^<g_
Venus's atmosphere includes dense cloud cover consisting primarily of sulfuric acid droplets and solid sulfur. There are several layers to the atmosphere, of varying thickness and haziness._^<g_
Observations at several sites indicate that Venus's crust consists largely of granite and basaltic rock. Radioactive isotopes of uranium, thorium, and potassium have been found there. Venus is dominated by low-lying volcanic plains, but there are also continent-sized highland regions with mountain ranges, volcanoes, and rift systems._^<g_
Earth's continental land masses have risen above the mantle because they consist of low-density rock. The continents are thought to have drifted from two great supercontinents, Gondwanaland and Pangea, 200 million years ago._^<g_
The oceans sprung up initially from hydrated silicates in the Earth's mantle, probably due to volcanism. The oceans have grown gradually since. Ocean basins were created when the continents drifted from their original positions. The Indian Ocean is thought to have formed when India slid past Australia and rammed into Asia. The Indian Ocean is at the convergence of the African, Indian, and Antarctic crustal plates._^<g_
Beneath the crust of the Earth is the mantle, made of rock under great pressure; it periodically yields to stresses and can flow very slowly. It is thought to consist of molten iron and nickel, and is responsible for most of the planet's mass and volume. Earth's mantle is thought to be convecting due to the heat given off by the decay of radioactive materials. _^<g_
Temperature measurements indicate that there is a residual water-ice cap at Mars's north pole, but no comparable cap has been detected at its south pole. Polar caps are made of dust and ice. They hold most, if not all, of the water on Mars that once created craters and rivers there._^<g_
Among its diverse topography, Mars has numerous craters resulting from meteorites and comets landing there in the first billion years of the planet's existence. They consist of raised rims surrounded by heaps of ejected materials._^<g_
Mars appears to have a more rigid crust than Earth, and a weaker magnetic field. As a result, Mars lacks the protective magnetic shield that deflects much of the Sun's harmful radiation._^<g_
Jupiter's atmosphere is believed to have three layers of clouds, each of differing chemical composition and each colored by different chemicals. The lowest layer consists of water ice or droplets; the middle, crystals of a compound of ammonia plus hydrogen sulfide; the lowest, ammonia ice. The clouds exhibit color banding parallel to the equator. The bands are disrupted by irregularities, the largest of which is the Great Red Spot._^<g_
At the very center of Jupiter there may be a rocky core. It is uncertain what caused Jupiter's core to form. The fact that the planet radiates more energy than it receives from the Sun indicates the presence of an internal source of energy._^<g_
Jupiter is composed primarily of hydrogen (approximately 88 percent) and helium (approximately 11 percent). Temperature and pressure increases toward the center of the planet are responsible for changes in the hydrogen's state from gas, to liquid, to liquid metal. Deep in the interior of Jupiter, tremendous pressure is thought to compresses hydrogen into a hot, molten metal. _^<g_
Located between Saturn's A and B rings, the Cassini division is named for Giovanni Domenico Cassini. He found that Saturn's ring is double rather than continuous and consists of a swarm of tiny satellites, each of which follows its own orbit in nearly the same plane. Astronomers believe the ring system may be the remains of a moon that broke up long ago, or perhaps material that might have formed a moon but never did._^<g_
Saturn has a deep fluid envelope made almost entirely of hydrogen and helium, with traces of methane, ethane, phosphine, and acetylene. Below Saturn's relatively opaque cloud layer is an extensive clear hydrogen-helium atmosphere. Beneath that, there is a gaseous layer, a liquid metallic hydrogen layer, and a dense core made of rocks and perhaps liquid water, methane, and ammonia. The ratio of hydrogen to helium is believed to decrease with depth._^<g_
Uranus's thin outer atmosphere consists of hydrogen, helium, and neon. It covers a dense and icy atmosphere of water, ammonia, and methane. The apparent blue green color of the planet is caused by methane's absorption of red light._^<g_
A set of at least 11 narrow, dark rings, which may be made of chunks of ice with a dark coating, circles the planet. The absence of small particles in the rings means possibly that they are relatively young, or are replaced by the breakup of small satellites. Images from Voyager 2 indicate the possible existence of 100 or more additional smaller rings of smaller particles._^<g_
The Great Dark Spot, a large, dark storm system that is part of Neptune's fast-moving weather system, seems to have moved; in fact, the original system has died down and a new one has sprouted in Neptune's northern hemisphere._^<g_
"Scooter," a comparatively small, dark storm system with a bright core of feathery clouds, was first spotted by Voyager 2. It is so named because, in relation to the Great Dark Spot, it travels quickly around Neptune's atmosphere._^<g_
Neptune's atmosphere consists mainly of hydrogen and helium, but also includes methane, which gives the planet its deep blue color. Methane is present in crystal form in the dynamic, rapidly changing cirrus clouds which surround it. Neptune's fierce weather system is caused by heat rising from deep within the planet. Beneath the atmosphere there seems to be a superheated "ocean" of water, methane, and ammonia; the planet may have a rocky core. _^<g_
Pluto is believed to have two bright polar ice caps, probably consisting of frozen nitrogen, possibly also including solid methane and carbon monoxide._^<g_
The methane frost of Pluto's crust is highly reflective and unevenly distributed. It is believed that some of the methane frost sublimates from solid to gas as a result of exposure to the Sun. The light and dark areas may indicate that different areas of Pluto's surface are covered with frost during different seasons._^<g_
_^<n__^<b_Main elements in body:_^>b_ oxygen, hydrogen, carbon, nitrogen (together account for nearly 95% of total body weight)_^<n__^<b_Main compound:_^>b_ water (roughly 60% of total body weight)_^<n__^<b_Number of cells at conception:_^>b_ 1_^<n__^<b_Number of cells in adult:_^>b_ 100 trillion_^<n__^<b_Main types of tissues:_^>b_ epithelial, muscle, nerve, connective_^<n__^<b_Largest organ:_^>b_ skin (about 20 square feet in adult)_^<n__^<g_
Blood leaves the heart by way of the aortic arch and travels through smaller and smaller arteries into capillaries, from which oxygen and nutrients pass to the cells of body tissues._^<g_
The pulmonary artery circulates oxygen-poor blood to the lungs, where oxygen is absorbed and carbon dioxide is released._^<g_
The four pulmonary veins carry oxygen-enriched blood back to the left atrium of the heart._^<g_
_^<n__^<b_Weight:_^>b_ about 10 to 12 ounces (about 0.5% of total body weight)_^<n__^<b_Length of cardiac cycle (diastole and systole):_^>b_ 0.8 seconds_^<n__^<b_Average heart rate, newborn baby:_^>b_ up to 150 beats a minute_^<n__^<b_Average heart rate, adult:_^>b_ about 72 beats a minute; more than 2.5 billion beats in an average lifetime_^<n__^<b_Amount of blood pumped:_^>b_ about 5 quarts per minute_^<n__^<b_Pacemaker location:_^>b_ where superior vena cava joins the right atrium_^<n__^<b_"Lub" sound:_^>b_ closing of tricuspid and mitral valves_^<n__^<b_"Dub" sound:_^>b_ closing of pulmonary and aortic valves _^<n__^<b_Volume of each heart chamber:_^>b_ about 2.5 ounces_^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P50056_Artificial heart_^>a__^<n__^<a!P45257_Harvey's illustration of blood circulation_^>a__^<n__^<a!P50120_Heart-lung machine_^>a__^<n__^<g_
In addition to secreting digestive enzymes, the pancreas secretes insulin and glucagon, which help maintain proper blood sugar levels._^<g_
_^<n__^<b_Amount of blood:_^>b_ about 6 quarts (adult)_^<n__^<b_Blood components:_^>b_ fluid (plasma) and formed elements (red blood cells, white blood cells, platelets)_^<n__^<b_Total length of blood vessels:_^>b_ over 65,000 miles_^<n__^<b_Largest artery:_^>b_ aorta_^<n__^<b_Largest veins:_^>b_ inferior and superior vena cava_^<n__^<b_Capillary size:_^>b_ about 0.04 inch long and 8 to 10 microns in diameter_^<n__^<b_Total surface area of capillaries:_^>b_ about 1.5 acres_^<n__^<b_Common disorders:_^>b_ heart attack, stroke, hypertension, aneurysm, Raynaud's disease, thrombophlebitis, varicose veins_^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P50056_Artificial heart_^>a__^<n__^<a!P45257_Harvey's illustration of blood circulation_^>a__^<n__^<a!P50120_Heart-lung machine_^>a__^<n__^<g_
_^<n__^<b_Length of esophagus:_^>b_ 9 to 10 inches (adult)_^<n__^<b_Length of stomach:_^>b_ less than 8 inches_^<n__^<b_Capacity of stomach:_^>b_ about 3.5 pounds of food (adult)_^<n__^<b_Length of small intestine:_^>b_ 16.4 to 19.7 feet (adult)_^<n__^<b_Length of large intestine:_^>b_ about 5 feet (adult)_^<n__^<b_Length of appendix:_^>b_ 1 to 8 inches_^<n__^<b_Stool production:_^>b_ approximately 9 ounces daily, of which 10 to 20% is bacteria_^<n__^<b_Common disorders:_^>b_ stomachache, constipation, diarrhea, dysentery, appendicitis, ulcers, gallstones, cancer_^<n__^<g_
_^<n_Distance from Earth (mean): 398,115 km; 238,869 mi; .0025AU_^<n_Length of year (in Earth time): 365.26 days_^<n_Average orbital speed: 1.1 km/sec; .64 mi/sec_^<n_Rotation period (in Earth time): 27 days_^<n_Mass (Earth=1): .012_^<n_Density (g/cu cm): 3.34_^<n_Diameter at equator: 3,476 km; 2,160 mi_^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P39484_Apollo 11: Lunar Module rises from the Moon_^>a__^<n__^<a!P49321_Apollo 11: Aldrin and U.S. flag_^>a__^<n__^<a!P49396_Apollo 11: Armstrong's footprint on the Moon_^>a__^<n__^<g__^<b_Table_^>b__^<n__^<a!B40405_Luna Flights_^>a__^<n__^<g__^<b_Movie_^>b__^<n__^<a!C38254_Apollo 11 Moon Landing_^>a__^<n__^<g_
_^<n_Distance from Earth (mean): 398,115 km; 238,869 mi; .0025AU_^<n_Rotation period (in Earth time): 27 days_^<n_Synodic revolution period (time between repeated lunar phases): 29 days, 12 hours_^<n_Sidereal revolution period (1 revolution around Earth): 27 day, 7 hours_^<n_Average reflectivity: 10%_^<n_Length of day (in Earth time): 14 days_^<n__^<g_
The pituitary gland is located in the brain. Human growth hormone is secreted from its anterior lobe._^<g_
The thyroid glands, along with the parathyroid glands, produce a number of hormones, such as thyroxine._^<g_
The adrenal glands (located on top of the kidneys) are composed of two different layers, each of which functions as a separate gland: the cortex, which secretes the hormones aldosterone and the corticosteroids; and the medulla, which makes epinephrine and norepinephrine._^<g_
In addition to secreting digestive enzymes, the pancreas secretes insulin and glucagon, which help maintain proper blood sugar levels._^<g_
Ovaries secrete sex hormones including estrogens, progesterone, and the peptide hormone relaxin._^<g_
Testes secrete male sex hormones, or androgens, including testosterone._^<g_
_^<n__^<b_Largest vessels:_^>b_ thoracic duct and right lymphatic duct; enter left and right subclavian veins, respectively_^<n__^<b_Largest organ in system:_^>b_ spleen (3.5 to 8.0 ounces)_^<n__^<b_Types of tonsils:_^>b_ palatine (between the arches that extend from the uvula to the floor of the mouth); lingual (on the upper surface of each side of the back of the tongue); pharyngeal, usually referred to as the adenoids (at the back of the throat)_^<n__^<b_Spleen blood flow:_^>b_ all of the blood passes through the spleen about every 90 minutes_^<n__^<b_Distribution of lymph nodes:_^>b_ most abundant in the neck, armpit, groin, and around the large blood vessels in the abdomen and chest_^<n__^<b_Common disorders:_^>b_ edema, tonsillitis, lymphoma (including Hodgkin's disease)_^<n__^<g_
In humans, blood filters through the spleen once every 90 minutes. The spleen filters out waste products and worn-out red blood cells._^<g_
_^<n__^<b_Number of muscles:_^>b_ about 700 (skeletal)_^<n__^<b_Weight of muscles:_^>b_ about 40 to 50% of body weight_^<n__^<b_Largest muscle:_^>b_ buttock (formed of 3 gluteal muscles)_^<n__^<b_Smallest muscle:_^>b_ stapedius (in middle ear)_^<n__^<b_Common disorders:_^>b_ myositis, paralysis, muscular dystrophy, myasthenia gravis_^<n__^<g_
_^<b_Table_^>b__^<n__^<a!B37927_Exercise, Effect on Cardiovascular System_^>a__^<n__^<g_
_^<n__^<a!T22901_muscle_^>a__^<n__^<a!T22902_muscle contraction_^>a__^<n__^<a!T32074_tendon_^>a__^<n__^<a!T32566_tissue, animal and plant_^>a__^<n__^<g_
_^<n__^<b_Flexor muscles:_^>b_ bring adjacent body parts closer together _^<n__^<b_Extensor muscles:_^>b_ move adjacent body parts apart_^<n__^<b_Abductor muscles:_^>b_ move a part away from the rest of the body_^<n__^<b_Adductor muscles:_^>b_ move a part toward the rest of the body_^<n__^<b_Pronator muscles:_^>b_ turn a part, such as the hand, face up_^<n__^<b_Supinator muscles:_^>b_ turn a part, such as the hand, face down_^<n__^<g_
_^<b_Table_^>b__^<n__^<a!B37927_Exercise, Effect on Cardiovascular System_^>a__^<n__^<g_
_^<n__^<a!T22901_muscle_^>a__^<n__^<a!T22902_muscle contraction_^>a__^<n__^<a!T32074_tendon_^>a__^<n__^<a!T32566_tissue, animal and plant_^>a__^<n__^<g_
_^<n__^<b_Skeletal muscles, shape:_^>b_ cigar-shaped, 20 to 80 microns in diameter_^<n__^<b_Skeletal muscles, control:_^>b_ controlled by central nervous system_^<n__^<g_
_^<b_Table_^>b__^<n__^<a!B37927_Exercise, Effect on Cardiovascular System_^>a__^<n__^<g_
_^<n__^<a!T22901_muscle_^>a__^<n__^<a!T22902_muscle contraction_^>a__^<n__^<a!T32074_tendon_^>a__^<n__^<a!T32566_tissue, animal and plant_^>a__^<n__^<g_
_^<n__^<b_Basic unit:_^>b_ neuron (nerve cell)_^<n__^<b_Weight of brain:_^>b_ about 51 ounces (adult)_^<n__^<b_Cells in brain:_^>b_ about 100 billion neurons and 10 trillion glial cells_^<n__^<b_Synapses in brain:_^>b_ about 100 quadrillion_^<n__^<b_Cerebral cortex, thickness:_^>b_ 0.06 to 0.1 inch_^<n__^<b_Cerebral cortex, area:_^>b_ about 388 square inches_^<n__^<b_Spinal cord diameter:_^>b_ about 0.4 inch_^<n__^<b_Neurons, length of axon:_^>b_ from less than 0.04 inch in brain to as much as 40 inches (from spinal cord to foot)_^<n__^<b_Common disorders:_^>b_ headache, stroke, tumors, epilepsy, paralysis, multiple sclerosis, Parkinson's disease, Alzheimer's disease, cerebral palsy, multiple sclerosis, Down syndrome_^<n__^<g_
_^<n__^<a!T4569_brain (I)_^>a__^<n__^<a!T10471_ear_^>a__^<n__^<a!T11561_eye_^>a__^<n__^<a!T23398_nervous system_^>a__^<n__^<a!T23426_neurobiology_^>a__^<n__^<a!T23903_nose_^>a__^<n__^<a!T24770_pain_^>a__^<n__^<a!T27417_reflex_^>a__^<n__^<a!T29401_senses and sensation_^>a__^<n__^<a!T30675_spinal cord_^>a__^<n__^<a!T31882_taste and smell_^>a__^<n__^<a!T32695_tongue_^>a__^<n__^<g_
_^<n__^<b_Location of eye:_^>b_ in a bony socket, the orbit_^<n__^<b_Muscles attached to eye:_^>b_ 6_^<n__^<b_Lacrimal glands:_^>b_ near outer portion of eyebrows; produce tear fluid_^<n__^<b_Meibomian glands:_^>b_ in eyelid; produce an oily fluid_^<n__^<b_Size of eyeball:_^>b_ about 1 inch in diameter_^<n__^<b_Light-sensitive cells on retina:_^>b_ rods (important in black-white vision), cones (responsible for color vision)_^<n__^<b_Number of light-sensitive cells:_^>b_ about 130 million per retina_^<n__^<g_
_^<n__^<a!T4569_brain (I)_^>a__^<n__^<a!T10471_ear_^>a__^<n__^<a!T11561_eye_^>a__^<n__^<a!T23398_nervous system_^>a__^<n__^<a!T23426_neurobiology_^>a__^<n__^<a!T23903_nose_^>a__^<n__^<a!T24770_pain_^>a__^<n__^<a!T27417_reflex_^>a__^<n__^<a!T29401_senses and sensation_^>a__^<n__^<a!T30675_spinal cord_^>a__^<n__^<a!T31882_taste and smell_^>a__^<n__^<a!T32695_tongue_^>a__^<n__^<g_
The sclera - the opaque, white, outermost layer of the eye wall - is commonly known as the white of the eye. The sclera covers approximately five-sixths of the surface of the eyeball._^<g_
The choroid is the thin vascular tissue that separates the inner part of the sclera from the photosensitive part of the eye, the retina. The choroid is heavily pigmented and interlaced with blood vessels._^<g_
The retina - the innermost layer of the eye wall - is extremely sensitive to light, converting the energy of light waves into nerve impulses, which are transmitted along the optic nerve to the brain._^<g_
The lens is an elastic structure composed of a jellylike material that is transparent in a healthy eye. The lens and its supporting ligament divide the interior of the eyeball. There are three fluid-filled chambers in the eye._^<g_
The cornea is a transparent, colorless continuation of the sclera that lies directly over the pupil of the eye. The cornea contains no blood vessels, but has many nerve endings and is extremely sensitive to touch. It's kept moist by the constant secretion of tears from glands in the eyelids._^<g_
The aqueous body, which helps maintain the forward curve of the cornea, contains a watery solution called aqueous humor, which closely resembles plasma in composition._^<g_
The iris - the colored portion of the eye - is a diaphragm in the eye that, through contraction and expansion, controls the amount of light entering the eye. The central opening in the iris is the pupil._^<g_
The vitreous body - the largest of the eye's fluid spaces and the one occupying the central cavity of the eyeball - is a chamber filled with a jellylike substance called vitreous humor, which contains important nutrients for eye cells and maintains intraocular pressure._^<g_
The optic nerve contains fibers to the brain that emenate from the optic disk. The optic disk, located in the nasal half of the eyeball, is the area where nerve fibers have displaced all other retinal cells, making this region of the eye insensitive to light. This area is commonly known as the blind spot._^<g_
_^<n__^<b_Length of ear canal:_^>b_ less than 1 inch_^<n__^<b_Middle ear:_^>b_ filled with air_^<n__^<b_Inner ear:_^>b_ filled with fluid_^<n__^<b_Length of cochlear tube:_^>b_ nearly 1.5 inch_^<n__^<b_Number of hair cells in inner ear:_^>b_ about 25,000_^<n__^<b_Human hearing range:_^>b_ between 30 and 20,000 cycles per second (Hertz)_^<n__^<b_Characteristics of sound:_^>b_ amplitude (intensity), pitch, tone (quality)_^<n__^<g_
_^<n__^<a!T4569_brain (I)_^>a__^<n__^<a!T10471_ear_^>a__^<n__^<a!T11561_eye_^>a__^<n__^<a!T23398_nervous system_^>a__^<n__^<a!T23426_neurobiology_^>a__^<n__^<a!T23903_nose_^>a__^<n__^<a!T24770_pain_^>a__^<n__^<a!T27417_reflex_^>a__^<n__^<a!T29401_senses and sensation_^>a__^<n__^<a!T30675_spinal cord_^>a__^<n__^<a!T31882_taste and smell_^>a__^<n__^<a!T32695_tongue_^>a__^<n__^<g_
_^<n__^<b_Skin area:_^>b_ about 20 square feet (adult)_^<n__^<b_Skin weight:_^>b_ about 8.5 to 10 pounds (adult)_^<n__^<b_Skin thickness:_^>b_ from about 0.04 inch (eyelids) to about 0.08 to 0.12 inch (back, palms, soles)_^<n__^<b_Areas with heavy concentration of touch receptors:_^>b_ tongue, lips, finger pads_^<n__^<b_Areas with low concentration of touch receptors:_^>b_ back, legs_^<n__^<g_
_^<n__^<a!T4569_brain (I)_^>a__^<n__^<a!T10471_ear_^>a__^<n__^<a!T11561_eye_^>a__^<n__^<a!T23398_nervous system_^>a__^<n__^<a!T23426_neurobiology_^>a__^<n__^<a!T23903_nose_^>a__^<n__^<a!T24770_pain_^>a__^<n__^<a!T27417_reflex_^>a__^<n__^<a!T29401_senses and sensation_^>a__^<n__^<a!T30675_spinal cord_^>a__^<n__^<a!T31882_taste and smell_^>a__^<n__^<a!T32695_tongue_^>a__^<n__^<g_
_^<n__^<b_Passages in nose:_^>b_ two, separated by the nasal septum_^<n__^<b_Ciliated cells in nose:_^>b_ millions_^<n__^<b_Goblet cells, in nasal lining:_^>b_ produce mucus_^<n__^<b_Number of sinuses:_^>b_ about 12 on each side of nose, embedded within facial bones_^<n__^<g_
_^<n__^<a!T4569_brain (I)_^>a__^<n__^<a!T10471_ear_^>a__^<n__^<a!T11561_eye_^>a__^<n__^<a!T23398_nervous system_^>a__^<n__^<a!T23426_neurobiology_^>a__^<n__^<a!T23903_nose_^>a__^<n__^<a!T24770_pain_^>a__^<n__^<a!T27417_reflex_^>a__^<n__^<a!T29401_senses and sensation_^>a__^<n__^<a!T30675_spinal cord_^>a__^<n__^<a!T31882_taste and smell_^>a__^<n__^<a!T32695_tongue_^>a__^<n__^<g_
_^<n__^<b_Taste receptors:_^>b_ sweet, salt, sour, bitter_^<n__^<b_Number of taste buds:_^>b_ from hundreds to tens of thousands, depending on individual_^<n__^<b_People who are supertasters:_^>b_ up to 1,100 taste buds per square centimeter of tongue; 20% of population_^<n__^<b_People who are medium tasters:_^>b_ average 184 taste buds per square centimeter; 60% of population_^<n__^<b_People who are nontasters:_^>b_ as few as 11 buds per square centimeter; 20% of population_^<n__^<b_Nerves from each taste bud:_^>b_ chorda tympani (sends signals to brain), trigeminal (senses pain, temperature, touch)_^<n__^<g_
_^<n__^<a!T4569_brain (I)_^>a__^<n__^<a!T10471_ear_^>a__^<n__^<a!T11561_eye_^>a__^<n__^<a!T23398_nervous system_^>a__^<n__^<a!T23426_neurobiology_^>a__^<n__^<a!T23903_nose_^>a__^<n__^<a!T24770_pain_^>a__^<n__^<a!T27417_reflex_^>a__^<n__^<a!T29401_senses and sensation_^>a__^<n__^<a!T30675_spinal cord_^>a__^<n__^<a!T31882_taste and smell_^>a__^<n__^<a!T32695_tongue_^>a__^<n__^<g_
_^<n__^<b_Ovary size:_^>b_ comparable to a large grape_^<n__^<b_Testis size:_^>b_ about 2 inches long, 1 inch thick_^<n__^<b_Ovum size:_^>b_ about 1/300 inch in diameter_^<n__^<b_Sperm size:_^>b_ about 1/230 inch long_^<n__^<b_Number of ova:_^>b_ about 400 during a woman's reproductive lifetime_^<n__^<b_Number of sperm:_^>b_ millions produced daily; 300 million to 400 million in an ejaculate_^<n__^<b_Reproductive hormones:_^>b_ sex hormones (androgens, estrogen, progestins), gonadotropins_^<n__^<b_Commons disorders:_^>b_ sexually transmitted diseases (herpes, chlamydia, syphilis, etc.), cancer_^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P39983_Human fetus at 12 weeks_^>a__^<n__^<a!P39961_Human fetus at 14 weeks_^>a__^<n__^<a!P39963_Human fetus at 5 months_^>a__^<n__^<a!P39979_Human fetus at 5-6 weeks_^>a__^<n__^<a!P39981_Human fetus at 7 weeks_^>a__^<n__^<a!P39977_Ovum, human_^>a__^<n__^<a!P39974_Sperm, human_^>a__^<n__^<g_
_^<n__^<a!T1925_artificial insemination_^>a__^<n__^<a!T9507_development, human_^>a__^<n__^<a!T10673_egg_^>a__^<n__^<a!T10946_embryo_^>a__^<n__^<a!T11912_fertilization_^>a__^<n__^<a!T16771_in vitro fertilization_^>a__^<n__^<a!T26475_pregnancy and birth_^>a__^<n__^<a!T27529_reproduction_^>a__^<n__^<a!T27530_reproductive system, human_^>a__^<n__^<a!T29529_sexual intercourse_^>a__^<n__^<a!T30641_sperm_^>a__^<n__^<g_
The reproductive structures include the two ovaries, which produce the ovum, and the uterus, which is where babies grow until they are ready to be born. Each ovary is connected to the top of the uterus by a fallopian tube._^<g_
Each menstrual cycle, a mature oocyte (egg) is released from the ovary, and the lining of the uterus thickens to create an environment suitable for the development of a fetus. If fertilization does not occur, the lining is shed._^<g_
The vagina is the sheath that receives the penis during intercourse. The vagina is linked to the interior of the uterus, or womb, by the cervical canal._^<g_
The urethra receives fluids from the seminal vesicles, prostate, and Cowper's gland._^<g_
The penis is used both for transporting sperm into the female reproductive system and for eliminating urine._^<g_
After sperm are produced in the seminiferous tubules, they move through the testes to another duct system, the epididymis. There they age for approximately two weeks before moving to the vas deferens._^<g_
The uppermost layer of the Earth's mantle lies just below the crust. It is cool and hence strong, whereas the underlying mantle is warmer, contains partial melting and low strength. The transitional area between the upper mantle and the mantle is termed the Mohorovicic discontinuity, or simply, the Moho._^<g_
_^<n__^<b_Number of breaths, at rest:_^>b_ about 12 to 14 a minute (adult)_^<n__^<b_Lung capacity:_^>b_ 5 quarts of air (adult)_^<n__^<b_Number of alveoli:_^>b_ about 350 million per lung_^<n__^<b_Respiratory surface of alveoli:_^>b_ about 375 square feet per lung_^<n__^<b_Amount of air taken in with each breath:_^>b_ about 20.5 cubic inches_^<n__^<b_Amount of oxygen removed from air, at rest:_^>b_ about 250 milliliters per minute_^<n__^<b_Amount of carbon dioxide exhaled, at rest:_^>b_ about 200 milliliters per minute_^<n__^<b_Aerobic capacity:_^>b_ maximum sustained rate of oxygen consumption during exercise; usually 8 to 12 times the resting rate_^<n__^<b_Common disorders:_^>b_ bronchitis, pneumonia, asthma, cancer, emphysema_^<n__^<g_
_^<n__^<b_Main types of joints:_^>b_ fibrous, cartilaginous, synovial_^<n__^<b_Fibrous joints:_^>b_ bones held together by ligaments_^<n__^<b_Cartilaginous joints:_^>b_ bones held together by cartilage_^<n__^<b_Synovial joints:_^>b_ joints enclosed in a sleevelike capsule and freely movable; about 90% of all joints_^<n__^<b_Greatest range of motion:_^>b_ ball-and-socket joints_^<n__^<b_Largest joint:_^>b_ knee_^<n__^<b_Common disorders:_^>b_ dislocation, fracture, arthritis, osteoporosis_^<n__^<g_
_^<n__^<b_Size of kidney:_^>b_ about 4.4 inches long_^<n__^<b_Number of nephrons:_^>b_ at least 1 million per kidney_^<n__^<b_Size of a nephron:_^>b_ microscopic_^<n__^<b_Length of a nephron:_^>b_ about 1.8 inches_^<n__^<b_Length of ureter:_^>b_ 16 to 18 inches_^<n__^<b_Composition of urine:_^>b_ excess water, waste products of metabolism (urea, uric acid, etc.), excess ions (sodium, potassium, chloride, etc.)_^<n__^<b_Common disorders:_^>b_ kidney stones, tumors, damage from toxic agents and systemic and infectious diseases (e.g., analgesics, diabetes, mononucleosis)_^<n__^<g_
After waste liquid is processed in the kidney, it moves through the connecting tubes into the bladder. The bladder stores the urine until it is eliminated from the body._^<g_
Urine is passed out of the body through the urethra, which in males also serves as the conduit for the reproductive system._^<g_
The small intestine is the main site of digestion and absorption of food nutrients. Muscles surrounding the small intestine propel food through its components (the duodenum, the jejunum, and the ileum)._^<g_
Digestion begins in the mouth, where food is broken down through chewing. Enzymes in salivary secretions promote digestion._^<g_
Through peristalsis (rhythmic contractions of the muscular walls), the esophagus transfers food from the pharynx to the stomach. There, preliminary digestion takes place. _^<g_
The East Room, scene of many historic White House events, was designated by Hoban as the "Public Audience Room." It normally contains little furniture and is traditionally used for large gatherings, such as dances, after-dinner entertainments, concerts, weddings, funerals, award presentations, press conferences, and bill-signing ceremonies. _^<g_During the Civil War years and administration of Abraham Lincoln there was much activity in the East Room. At one time during the war Union troops occupied the room._^<g_Seven Presidents have lain in state in the East Room, including John F. Kennedy in November 1963. _^<g_
The State Dining Room, which now seats as many as 140 guests, was originally much smaller and served at various times as a drawing room, office, and Cabinet Room. Not until the Andrew Jackson administration was it called the "State Dining Room," although it had been used for formal dinners by previous Presidents._^<g_As the nation grew, so did the invitation list to official functions at the White House. After the renovation of 1902 by architects McKim, Mead & White, the room size was enlarged. Carved into the mantel below George P. A. Healy's portrait of President Lincoln is an inscription from a letter written by John Adams on his second night in the White House: I pray Heaven to Bestow the Best of Blessings on THIS HOUSE and on All that shall hereafter Inhabit it. May none but honest and Wise Men ever rule this roof. _^<g__^<g_
The "elliptic saloon," with the Yellow Oval Room above and the Diplomatic Reception Room below it, formed the most elegant architectural feature of Hoban's plans for the White House. The Blue Room has always been used as a reception room except for a brief period during the administration of John Adams when it served as the south entrance hall. During the Madison Administration, architect Benjamin Latrobe designed a suite of classical-revival furniture for the room, but only some working drawings remain; the furnishings were destroyed in the fire of 1814. _^<g_The color blue was first acquired during the administration of Martin Van Buren in 1837; he redecorated the oval salon and began the tradition of the "blue room". _^<g_
Although intended by White House architect James Hoban to be the "Common Dining Room," the Green Room has served many purposes since the White House was first occupied in 1800. The inventory of February 1801 indicates that it was first used as a "Lodging Room." Thomas Jefferson, the second occupant of the White House, used it as a dining room with a "canvas floor cloth, painted green," foreshadowing the present color scheme. James Madison made it a sitting room since his Cabinet met in the East Room next door, and the Monroes used it as the "Card Room." _^<g_The Green Room walls are covered with delicate green watered-silk fabric, originally chosen by Mrs. Jacqueline Kennedy in 1962, and support elegant paintings of various people and scenes._^<g_
In the early 19th Century, the Red Room - so named because the walls are covered by a red twill satin fabric with a gold scroll design in the border - served as "the President's Antichamber" for the Cabinet Room or President's Library next door. During the Madison Administration the antechamber became the "Yellow Drawing Room" and the scene of Dolley Madison's fashionable Wednesday night receptions. The room has usually served as a parlor or sitting room; recent Presidents have had small dinner parties here._^<g_
The Diplomatic Reception Room serves as an entrance to the White House from South Grounds for the family and for ambassadors arriving to present their credentials to the President. In the past, the area has had diverse uses: as a boiler and furnace room and as the site of President Franklin D. Roosevelt's fireside chats._^<g_
The Vermeil Room, sometimes called the Gold Room, was last refurbished in 1991; it serves as a display room and, for formal occasions, as a ladies' sitting room. The vermeil collection contains pieces from different services and includes the work of English Regency silversmith Paul Storr (1771-1844), the French Empire silversmith Jean-Baptiste-Claude Odiot (1763-1850), and Philip Rundell of London._^<g_
The Map Room was used by President Franklin D. Roosevelt as a situation room from which to follow the course of World War II and now serves as a private meeting room for the President or the First Lady. _^<g_In the room is a medicine chest that is believed to have belonged to President and Mrs. James Madison, and to have been rescued from the White House just before the building was burned during the War of 1812. A rare 1755 French version of a map charted by colonial surveyors Joshua Fry and Peter Jefferson (Thomas Jefferson's father) hangs on the east wall, covering a case of world maps presented by the National Geographic Society._^<g_
The "Presidential Collection Room," now the China Room, was designated by Mrs. Woodrow Wilson in 1917 to display the growing collection of White House china. The room was redecorated in 1970, retaining the traditional red color scheme determined by the portrait of Mrs. Calvin Coolidge--painted by Howard Chandler Christy in 1924. President Coolidge, who was scheduled to sit for Christy, was too occupied that day with events concerning the Teapot Dome oil scandal. So the President postponed his appointment, and Mrs. Coolidge posed instead._^<g_Almost every past President is represented in the China Room either by state or family china or glassware and an array of presidential china is on display there._^<g_
"Tubs Buckets and a variety of Lumber" cluttered Room 17 of the basement in February 1801, according to the first official White House inventory. The room served mainly as a laundry area until Theodore Roosevelt's renovation of the Ground Floor in 1902, when it was designated a "Gentlemen's Ante-Room." In 1935, it was remodeled as a library, and in 1961 a committee was appointed to select works representative of a full spectrum of American thought and tradition for the use of the President, his family, and his staff. This wide-ranging collection is still being augmented with Presidential papers._^<g_
Bitter cress, an herb of the mustard family, has a perennial rootstock, which each spring gives rise to erect annual stems that reach heights of 18 inches. It blooms in spring, and the flowers give rise to fruits that open explosively when mature, throwing the seeds up to 5 feet away from the plant._^<g_
Himalayan ibex are exceptional jumpers and climbers. The males grow massive backward-curving horns, which they use during mating season to duel each other. Except during mating season, males live in all-male herds, while does and young form their own groups. Ibex graze on grasses and herbs. _^<g_
Saxifrage is a small, hardy perennial herb native to mountains and rocky places in temperate America and Europe. The name saxifrage means "rock-splitter," which refers to the persistent manner in which the roots of these plants burrow into rocky hillsides and among stone crevices._^<g_
Bumblebees nest in cavities in the ground, such as old mouse or bird nests. In temperate climates, only the mated queens survive the winter. When spring arrives the queens select nesting sites and build wax cells in which the young are reared. The queen then gathers pollen and nectar to feed the young._^<g_
Long-horned meadow grasshoppers, named for their long antennae, are superb jumpers, relying on their strongly muscled hind legs to leap out of the reach of hungry predators. They are herbivorous, feeding on the prairie's grasses._^<g_
Gigartina belongs to the red algae, though it generally is dark brown or purplish in color. The fronds are covered with short bumps and may be curled at the edges. It grows in the lower intertidal zone, on the edges of tide pools and on rocks beaten by waves. _^<g_
Thick beds of green sea urchins are often found in the low intertidal zone. Their spines discourage predators. By moving the spines, a sea urchin can move short distances. Mingled among the spines are tubelike feet with suckers at the tips, which are used to attach the animal firmly to a rock or other solid surface._^<g_
_^<b_Pictures_^>b__^<n__^<a!P39499_Atlas rocket launches Mercury spacecraft_^>a__^<n__^<a!P49325_Chimpanzee in Mercury space flight_^>a__^<n__^<a!P39505_Explorer 1 launch_^>a__^<n__^<g__^<b_Tables_^>b__^<n__^<a!B44108_Vostok Program Flights _^>a__^<n__^<a!B44101_Voskhod Program Flights _^>a__^<n__^<g_
_^<n__^<a!T2077_astronaut_^>a__^<n__^<a!T11534_Explorer_^>a__^<n__^<a!T17907_Juno (rocket)_^>a__^<n__^<a!T21675_Mercury program_^>a__^<n__^<a!T23154_National Aeronautics and Space Administration_^>a__^<n__^<a!T27911_rockets and missiles_^>a__^<n__^<a!T28865_satellite, artificial_^>a__^<n__^<a!T30545_space programs, national_^>a__^<n__^<a!T30766_Sputnik_^>a__^<n__^<a!T33737_Vanguard_^>a__^<n__^<a!T34231_Vostok_^>a__^<n__^<a!T34230_Voskhod_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D46669_--Space Exploration_^>a__^<n__^<b_----Early Efforts_^>b__^<n__^<a!D47264_----Race to the Moon_^>a__^<n__^<a!D47812_----Looking Beyond_^>a__^<n__^<g_
_^<n__^<b_Sputnik I_^>b__^<n__^<b_Launch date:_^>b_ October 5, 1957_^<n__^<b_Diameter:_^>b_ 23 in_^<n__^<b_Weight:_^>b_ 184 lb_^<n__^<b_Scientific purpose:_^>b_ To investigate outer space and establish communications with Earth._^<n__^<b_Note:_^>b_ First successful deployment of an object into space. Served as the starting bell in the space race between the Soviet Union and the United States. _^<n__^<g__^<n__^<b_Sputnik 2_^>b__^<n__^<b_Launch date:_^>b_ November 3, 1957_^<n__^<b_Weight:_^>b_ 2,980 lb_^<n__^<b_Scientific purpose:_^>b_ To discover if living organisms could survive space conditions._^<n__^<b_Note:_^>b_ A dog named Laika was kept alive for ten days on the life supplies stored in Sputnik 2, proving that life could survive the conditions of space._^<n__^<g__^<n__^<b_Sputnik 3_^>b__^<n__^<b_Launch date:_^>b_ May 15, 1958_^<n__^<b_Weight:_^>b_ 2,980 lb_^<n__^<b_Scientific purpose:_^>b_ To conduct geophysical experiments in space._^<n__^<b_Note:_^>b_ Sputnik 3, containing many experiments, operated successfully for two years before orbital decay caused it to reenter the atmosphere and burn up._^<n__^<g_
_^<n__^<b_Explorer Program_^>b__^<n__^<b_Dates of operation:_^>b_ 1958-78_^<n__^<b_Number of missions:_^>b_ More than 50, using a variety of craft._^<n__^<b_Primary goal:_^>b_ To investigate Earth's shape, surface, atmosphere, ionosphere, and magnetosphere, and later, to investigate interplanetary space._^<n__^<g__^<n__^<b_Major Contributions of the Explorer Series_^>b__^<n__^<b_Explorer 1_^>b_ discovered, during the International Geophysical Year (1957-58), the Van Allen radiation belts that surround the Earth._^<n__^<b_Explorer 6_^>b_ transmitted the first televised cloud cover picture of Earth._^<n__^<b_Explorer 11_^>b_ was the first to find gamma rays from space._^<n__^<b_Explorer 35_^>b_ reported that the Moon had no detectable magnetic field._^<n__^<b_Explorer 38_^>b_ detected low-frequency radio waves from Jupiter._^<n__^<g_
_^<n__^<b_Vostok_^>b__^<n__^<b_Command module diameter:_^>b_ 7 ft 6 in_^<n__^<b_Command module weight:_^>b_ 4,600 lb_^<n__^<b_Total weight:_^>b_ 10,400 lb_^<n__^<b_Crew capacity:_^>b_ 1_^<n__^<g__^<n__^<b_Key Vostok Milestones_^>b__^<n__^<b_First man in space:_^>b_ Yuri Gagarin, April 12, 1961_^<n_-Gagarin reached a maximum altitude of 203 mi, and made one orbit of Earth._^<n__^<b_First woman in space:_^>b_ Valentina Tereshkova, June 16, 1963_^<n_-Tereshkova flew for 70.8 hours and made 48 orbits of Earth._^<n__^<g__^<n__^<b_Voskhod_^>b__^<n__^<b_Command module diameter:_^>b_ 7 ft 6 in_^<n__^<b_Command module weight:_^>b_ 4,600 lb_^<n__^<b_Total weight:_^>b_ 12,530 lb_^<n__^<b_Crew capacity:_^>b_ 3_^<n__^<g__^<n__^<b_Key Voskhod Milestones_^>b__^<n__^<b_First multiple-occupant space flight:_^>b_ Oct. 12, 1964_^<n__^<b_First tethered space walk:_^>b_ Aleksei Leonov, Mar. 18, 1965_^<n__^<g__^<b_Note:_^>b_ Because of an apparent emphasis on political significance at the expense of scientific goals and crew safety, the Voskhod has become a symbol of the dangers of politically motivated space projects._^<g_
_^<n__^<b_Project Mercury_^>b__^<n__^<b_Dates of operation:_^>b_ 1958-63_^<n__^<b_Number of manned flights:_^>b_ 6_^<n__^<b_Primary goal:_^>b_ Launching a man into orbit and returning him safely to Earth_^<n__^<g__^<n__^<b_Key Mercury Milestones_^>b__^<n__^<b_- Nov. 21, 1960:_^>b_ An emergency backup safety rocket is activated to lift the Mercury spacecraft away from the launch vehicle when the Redstone launcher rocket fails._^<n__^<b_- Jan. 31, 1961:_^>b_ A 37-lb chimpanzee named Ham is carried on a suborbital flight, from which he is recovered unharmed._^<n__^<b_- May 5, 1961:_^>b_ Navy Lt. Comdr. Alan B. Shepard, Jr., is launched 303 mi downrange aboard Mercury-Redstone 3. The capsule, Freedom 7, reaches an altitude of 116 mi._^<n__^<b_- July 1, 1961:_^>b_ After splashdown, Virgil I. Grissom narrowly escapes drowning when a hatch blows out prematurely and his capsule fills with water. He is rescued by a helicopter, but the capsule, Liberty Bell 7, sinks and is not recovered._^<n__^<b_- Feb. 20, 1962:_^>b_ Marine Lt. Col. John H. Glenn, Jr., flies a three-orbit (4 hr 55 min) mission in the Mercury-Atlas 6 spacecraft, becoming the first American to fly in orbit._^<n__^<g__^<n__^<b_Mercury Spacecraft_^>b__^<n__^<b_Capsule height:_^>b_ 9 ft 7 in_^<n__^<b_Capsule weight:_^>b_ Less than 3,000 lb_^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P49084_Apollo Lunar Excursion Module_^>a__^<n__^<a!P39494_Apollo spacecraft docks with Soyuz_^>a__^<n__^<a!P39497_Apollo-Soyuz astronauts_^>a__^<n__^<g_
_^<n__^<a!T1572_Apollo program_^>a__^<n__^<a!T13373_Gemini program_^>a__^<n__^<a!T20249_Lunar Excursion Module_^>a__^<n__^<a!T20251_Lunar Rover_^>a__^<n__^<a!T22479_Moon_^>a__^<n__^<a!T23154_National Aeronautics and Space Administration_^>a__^<n__^<a!T27911_rockets and missiles_^>a__^<n__^<a!T30539_Soyuz_^>a__^<n__^<a!T30541_space exploration_^>a__^<n__^<a!T30545_space programs, national_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D46669_--Space Exploration_^>a__^<n__^<a!D46760_----Early Efforts_^>a__^<n__^<b_----Race to the Moon_^>b__^<n__^<a!D47812_----Looking Beyond_^>a__^<n__^<g_
_^<n__^<b_Project Gemini_^>b__^<n__^<b_Dates of operation:_^>b_ 1965-66_^<n__^<b_Number of manned flights:_^>b_ 10_^<n__^<b_Primary goal:_^>b_ To perfect space rendezvous and docking techniques for use on lunar missions and to explore the effects of extravehicular activity in space._^<n__^<b_First extravehicular activity:_^>b_ June 3, 1965, Gemini 4_^<n__^<b_First space rendezvous:_^>b_ December 15, 1965, Geminis 6 & 7_^<n__^<b_First space docking:_^>b_ March 16, 1966, Gemini 8 and Agena target rocket_^<n__^<g__^<n__^<b_Gemini Spacecraft_^>b__^<n__^<b_Length:_^>b_ 19 ft_^<n__^<b_Diameter:_^>b_ 10 ft (at the blunt end)_^<n__^<b_Weight:_^>b_ 8,000 lb_^<n__^<b_Crew capacity:_^>b_ 2_^<n__^<g_
_^<n__^<b_Soyuz Program_^>b__^<n__^<b_Dates of operation:_^>b_ 1967-present_^<n__^<b_Number of manned flights:_^>b_ 80+ (1997)_^<n__^<b_Primary goal:_^>b_ Originally, to land humans on the surface of the Moon and return them safely to Earth. Following the success of the U.S. Apollo program, to carry crews and cargo to and from Soviet/Russian space stations_^<n__^<g__^<n__^<b_Soyuz Components_^>b__^<n__^<b_Command Module:_^>b_ Carries the crew. Original crew capacity was 3. That capacity was reduced to 2 after safety equipment was added in 1971. The improved Soyuz T model, introduced in 1979, restored crew capacity to 3, while maintaining the added safety equipment._^<n__^<g__^<b_Equipment Module:_^>b_ Attached to the rear of the command module, it contains electrical power equipment and rocket engines._^<g__^<b_Orbital Module:_^>b_ Provides additional working space and is attached forward of the command module. Improved docking equipment was attached to the module in the Soyuz TM model, introduced in 1987._^<g_
_^<n__^<b_Apollo Program_^>b__^<n__^<b_Dates of operation:_^>b_ 1968-75_^<n__^<b_Number of manned flights:_^>b_ 15_^<n__^<b_Primary goal:_^>b_ To land humans on the surface of the Moon and return them safely to Earth_^<n__^<b_Number of successful lunar landings:_^>b_ 6_^<n__^<b_First Moon landing:_^>b_ July 20, 1969, Apollo 11_^<n__^<b_Second Moon landing:_^>b_ November 19, 1969, Apollo 12_^<n__^<b_Third Moon landing:_^>b_ February 5, 1971, Apollo 14_^<n__^<b_Fourth Moon landing:_^>b_ July 30, 1971, Apollo 15_^<n__^<b_Fifth Moon landing:_^>b_ April 20, 1972, Apollo 16_^<n__^<b_Sixth (Last) Moon landing:_^>b_ December 11, 1972, Apollo 17_^<n__^<g__^<n__^<b_Combined Command and Service Module (CSM)_^>b__^<n__^<b_Length:_^>b_ 34 ft_^<n__^<b_Diameter:_^>b_ 10 ft (at the blunt end)_^<n__^<b_Crew capacity:_^>b_ 3_^<n__^<b_Cabin oxygen pressure:_^>b_ 5 lb/sq in_^<n__^<b_Engine thrust:_^>b_ 21,500 lb_^<n__^<g_
_^<n__^<b_First Moon Landing_^>b__^<n__^<b_Mission:_^>b_ Apollo 11_^<n__^<o!E345__^<o!E345__^<b_CSM:_^>b_ Columbia_^<n__^<o!E345__^<o!E345__^<b_LEM:_^>b_ Eagle_^<n__^<b_Astronauts:_^>b_ Neil A. Armstrong, Col. Edwin "Buzz" Aldrin, Lt. Col. Michael Collins_^<n__^<b_Launch date:_^>b_ July 16, 1969_^<n__^<b_Lunar touchdown date:_^>b_ July 20, 1969_^<n__^<o!E345__^<o!E345__^<b_Touchdown site:_^>b_ Mare Tranquillitatis (Sea of Tranquillity)_^<n__^<o!E345__^<o!E345__^<b_First step on lunar surface:_^>b_ Neil Armstrong, 10:56 PM EDT_^<n__^<o!E345__^<o!E345__^<b_Extravehicular activity duration:_^>b_ 2 hours, 13 minutes_^<n__^<o!E345__^<o!E345__^<b_Collections:_^>b_ 53.61 lb of rock and dirt samples_^<n__^<b_Lunar liftoff:_^>b_ July 22, 1969, 12:56 AM EDT_^<n__^<b_Pacific splashdown date:_^>b_ July 24, 1969_^<n__^<g__^<b_Note:_^>b_ In his autobiography, Buzz Aldrin described the pressures of returning to public life after his Moon journey, and his subsequent nervous breakdown and recovery. Neil Armstrong went on to serve as vice-chairman of a presidential commission appointed to investigate the destruction of the Space Shuttle Challenger in 1986, and Michael Collins became the director of the National Air and Space Museum of the Smithsonian Institution._^<g_
The numerous experimental devices deployed on the lunar surface have told us much about Earth's lone satellite. _^<g__^<n__^<b_Passive seismic:_^>b_ A total of 16 seismometers occur, but the Moon is seismically quieter than Earth._^<n__^<b_Lunar surface magnetometer:_^>b_ To measure solar and terrestrial magnetic fields._^<n__^<b_Solar wind spectrometer:_^>b_ To measure solar wind speed, direction, and density._^<n__^<b_Suprathermal ion detector:_^>b_ Ions from interplanetary storms and solar flares detected heat flow. Determined surface soil mean temperature of -67_^<o!E336_ C (90_^<o!E336_ F); at 90 cm (35 in) depth, -45_^<o!E336_ C (-49_^<o!E336_ F)._^<n__^<b_Lunar geology:_^>b_ Eyewitness accounts and photographs of the terrain._^<n__^<b_Laser-ranging retro-reflector:_^>b_ Laser on Earth and reflector on Moon determine mean lunar distance to within 5.9 in (13 cm)._^<n__^<b_Cosmic ray detector:_^>b_ Tracks in lexan and mica furnish information on cosmic ray sources._^<n__^<b_Portable magnetometer:_^>b_ Measurements of permanent magnetic fields show lunar materials magnetized 3-4 billion years ago._^<n__^<b_Traverse gravimeter:_^>b_ Information on substructure of Moon._^<n__^<b_Soil mechanics:_^>b_ Penetrometer shows lunar soil behavior similar to Earth soils._^<n__^<b_Far UV camera-spectrograph:_^>b_ Ultraviolet spectra of selected celestial sources._^<n__^<b_Lunar ejecta and meteorites:_^>b_ Film sensors detect high-velocity particle impacts._^<n__^<b_Lunar atmospheric composition:_^>b_ Mass spectrometer finds traces of argon, neon, hydrogen, and helium._^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P49440_Hubble Space Telescope, repair_^>a__^<n__^<a!P39529_Space Shuttle Challenger_^>a__^<n__^<a!P39527_Space Shuttle Discovery_^>a__^<n__^<a!P49339_Space Shuttle EVA_^>a__^<n__^<a!P41973_Voyager spacecraft_^>a__^<n__^<g__^<b_Tables_^>b__^<n__^<a!B43438_Soviet/Russian Space Stations _^>a__^<n__^<g_
_^<n__^<a!T22114_Mir_^>a__^<n__^<a!T23154_National Aeronautics and Space Administration_^>a__^<n__^<a!T25874_Pioneer_^>a__^<n__^<a!T27911_rockets and missiles_^>a__^<n__^<a!T28618_Salyut_^>a__^<n__^<a!T30087_Skylab_^>a__^<n__^<a!T30545_space programs, national_^>a__^<n__^<a!T30546_Space Shuttle_^>a__^<n__^<a!T30547_space station_^>a__^<n__^<a!T30549_Space Telescope_^>a__^<n__^<a!T34020_Viking_^>a__^<n__^<a!T34237_Voyager_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D46669_--Space Exploration_^>a__^<n__^<a!D46760_----Early Efforts_^>a__^<n__^<a!D47264_----Race to the Moon_^>a__^<n__^<b_----Looking Beyond_^>b__^<n__^<g_
_^<n__^<b_Viking Program_^>b__^<n__^<b_Primary goal:_^>b_ To explore the environments of Mars and its moons, Phobos and Deimos, and to land on the surface of Mars._^<n__^<g__^<n__^<b_Viking 1_^>b__^<n__^<b_Launch date:_^>b_ Aug. 20, 1975_^<n__^<b_Date of touchdown on Mars:_^>b_ July 20, 1976_^<n__^<b_Touchdown site on Mars:_^>b_ dry basin in the Chryse Planitia region_^<n__^<g__^<n__^<b_Viking 2_^>b__^<n__^<b_Launch date:_^>b_ Sept. 9, 1975_^<n__^<b_Date of touchdown on Mars:_^>b_ Sept. 3, 1976_^<n__^<b_Touchdown site on Mars:_^>b_ rocky plain of Utopia Planitia_^<n__^<g__^<b_Note:_^>b_ The craft discovered more water than was expected. The ice of the north polar cap is almost entirely made up of frozen water._^<g_
_^<n__^<b_Hubble Space Telescope (HST)_^>b__^<n__^<b_Dates of operation:_^>b_ 1990-present_^<n__^<b_Purpose:_^>b_ To allow greater, more accurate views of the universe, from beyond the image-compromising atmosphere._^<n__^<g__^<n__^<b_HST Instruments_^>b__^<n__^<b_Faint-object camera:_^>b_ has a small field of view, examines the ultraviolet, visible, and near-infrared regions of the spectrum_^<n__^<b_Wide-angle camera:_^>b_ has a field 40 times wider than the above camera, but less resolution_^<n__^<b_Photometer:_^>b_ measures the intensity of a beam of light ranging beyond visible light into the ultraviolet and infrared portions of the electromagnetic spectrum_^<n__^<b_High-resolution spectrograph:_^>b_ examines with high resolution power the component wavelengths of radiation beams_^<n__^<g__^<n__^<b_HST Housing_^>b__^<n__^<b_Diameter:_^>b_ 4.3 m (14 ft)_^<n__^<b_Length:_^>b_ 13 m (43 ft)_^<n__^<b_Distance from Earth:_^>b_ 613 km (381 mi)_^<n__^<g__^<b_Note:_^>b_ A 1993 Space Shuttle mission was required to repair a faulty HST mirror and to install a corrective camera for the main mirror. HST observations suggest the existence of 50 billion more galaxies than had previously been supposed._^<g_
_^<n__^<b_Salyut Space Station_^>b__^<n__^<b_Dates of operation:_^>b_ 1971-86_^<n__^<b_Number of stations deployed:_^>b_ 7_^<n__^<b_Scientific purpose:_^>b_ An Earth-orbiting laboratory, providing life-support for extended periods of human habitation, and working areas for crews conducting experiments and observations in space._^<n__^<g__^<n__^<b_Deployment Dates_^>b__^<n__^<b_Salyut 1:_^>b_ Apr. 19, 1971_^<n__^<b_Salyut 2:_^>b_ April 1973--did not function and never received cosmonauts_^<n__^<b_Salyut 3:_^>b_ June 1974_^<n__^<b_Salyut 4:_^>b_ Dec. 26, 1974_^<n__^<b_Salyut 5:_^>b_ June 22, 1976_^<n__^<b_Salyut 6:_^>b_ Sept. 29, 1977_^<n__^<b_Salyut 7:_^>b_ Apr. 19, 1982_^<n__^<g__^<n__^<b_Salyut Craft_^>b__^<n__^<b_Length:_^>b_ 13.5 m (44.3 ft)_^<n__^<b_Weight:_^>b_ 18,400 kg (40,565 lb)_^<n__^<b_Diameter:_^>b_ 4 m (13 ft)_^<n__^<g__^<b_Note:_^>b_ The retired Salyut 7, unused after 1986, remained in orbit until 1991, when it burned up while reentering the atmosphere._^<g_
_^<n__^<b_Space Shuttle Program_^>b__^<n__^<b_Dates of operation:_^>b_ 1981-present_^<n__^<b_Number of missions:_^>b_ 85+ (as of 1997)_^<n__^<b_Purpose:_^>b_ To provide and operate a reusable, large-crew spacecraft suitable for a wide range of scientific, commercial, retrieve-and-repair, and other missions._^<n__^<g__^<n__^<b_Shuttle Components_^>b__^<n__^<b_Orbiter_^>b__^<n__^<b_-Wingspan:_^>b_ 23.79 m (78.06 ft)_^<n__^<b_-Length:_^>b_ 37.2 m (122.2 ft)_^<n__^<b_-Payload bay:_^>b_ 4.6 m (15 ft) wide and 18.3 m (60 ft) long_^<n__^<b_-Main engine thrust (3):_^>b_ 213,000 kg (470,000 lb) per engine_^<n__^<b_-Classification during launch and in orbit:_^>b_ spaceship_^<n__^<b_-Classification after reentry:_^>b_ hypersonic glider_^<n__^<g__^<n__^<b_External tank_^>b__^<n__^<b_-Width:_^>b_ 8.38 m (27.56 ft)_^<n__^<b_-Height:_^>b_ 47 m (154.2 ft)_^<n__^<b_-Fuel capacity:_^>b_ 709,750 kg (1,565,000 lb) of liquefied propellants_^<n__^<g__^<n__^<b_Solid rocket boosters (2)_^>b__^<n__^<b_-Width:_^>b_ 3.7 m (12.14 ft)_^<n__^<b_-Height:_^>b_ 45.5 m (149.16 ft)_^<n__^<b_-Thrust:_^>b_ 1.20 million kg (2.65 million lb) per rocket_^<n__^<g_
_^<n__^<b_Pioneer Program_^>b__^<n__^<b_Dates of operation:_^>b_ 1958-95_^<n__^<b_Number of missions:_^>b_ 13, using a variety of craft._^<n__^<b_Primary goal:_^>b_ Lunar, solar/interplanetary and planetary exploration._^<n__^<g__^<n__^<b_Major Milestones of the Pioneer Program_^>b__^<n__^<b_Pioneer 5_^>b_, the first truly deep-space probe launched by the United States, reported on the interplanetary magnetic field and the solar wind out to more than 36 million km (22 million mi) from Earth._^<n__^<b_Pioneer 10_^>b_, the first spacecraft to pass through the asteroid belt between Mars and Jupiter, left the known solar system in 1983 after transmitting numerous photos of Jupiter and its moons._^<n__^<b_Pioneer 11_^>b_ discovered new rings around Saturn in 1979 and continued transmitting signals to Earth from beyond the solar system until 1995, when NASA stopped monitoring the weakened signals._^<n__^<b_Pioneer Venus 1 and Venus 2_^>b_ descended into Venus's atmosphere, found large amounts of argon-36 gas and proof that the planet is warmer over the polar regions than over the equator._^<n__^<g_
_^<n__^<b_Voyager Program_^>b__^<n__^<b_Primary goal:_^>b_ To explore the outer, giant planets of the solar system and their satellites._^<n__^<g__^<n__^<b_Voyager 1_^>b__^<n__^<b_Launch site:_^>b_ Kennedy Space Center_^<n__^<b_Launch date:_^>b_ Sept. 5, 1977_^<n__^<b_Closest approach to Jupiter:_^>b_ 170,000 mi, Mar. 5, 1979_^<n__^<b_Closest approach to Saturn:_^>b_ 78,000 mi, Nov. 12, 1980 _^<n__^<g__^<n__^<b_Voyager 2_^>b__^<n__^<b_Launch site:_^>b_ Cape Canaveral_^<n__^<b_Launch date:_^>b_ Aug. 20, 1977_^<n__^<b_Closest approach to Jupiter:_^>b_ 400,000 mi, July 9, 1979_^<n__^<b_Closest approach to Saturn:_^>b_ 63,000 mi, Aug. 25, 1981_^<n__^<b_Closest approach to Uranus:_^>b_ 50,000 mi, Jan. 24, 1986_^<n__^<b_Closest approach to Neptune:_^>b_ 3,100 mi, Aug. 25, 1989_^<n__^<g__^<b_Note:_^>b_ Scientists hope that at least one of the probes will continue to transmit data until it reaches the heliopause, the outer limit of the Sun's magnetic influence._^<g_
_^<n__^<b_Skylab Space Station_^>b__^<n__^<b_Dates of operation:_^>b_ 1973-74_^<n__^<b_Number of visiting crews:_^>b_ 3_^<n__^<b_Scientific purpose:_^>b_ An Earth-orbiting laboratory, providing living and working areas for crews conducting experiments and observations._^<n__^<g__^<n__^<b_Skylab Craft Sections (3)_^>b__^<n__^<b_Apollo telescope mount (ATM):_^>b_ carried instruments for observing the Sun in the visible, ultraviolet, and X-ray portions of the spectrum._^<n__^<b_Multiple docking adapter (MDA):_^>b_ held the controls for the telescope array and provided the docking port for the Apollo spacecraft that carried the crews to and from the Earth._^<n__^<b_Air-lock module (AM):_^>b_ housed various life-support, electrical, and communications systems. _^<n__^<g__^<b_Note:_^>b_ After 3 successful missions of 28, 59, and 84 days respectively, Skylab was deemed too impractical to continue until reusable spacecraft could be developed to supply it. The vessel decayed more rapidly than expected and on July 11, 1979, it entered the Earth's atmosphere and disintegrated, showering debris over the Indian Ocean and uninhabited regions of Australia._^<g_
_^<n__^<b_Mir Space Station_^>b__^<n__^<b_Dates of operation:_^>b_ 1986-present_^<n__^<b_Scientific purpose:_^>b_ An Earth-orbiting laboratory, providing life support for extended periods of human habitation, and working areas for crews conducting experiments and observations in space._^<n__^<g__^<n__^<b_Mir Craft_^>b__^<n__^<b_Length:_^>b_ 17 m (56 ft)_^<n__^<b_Diameter:_^>b_ 4 m (13 ft)_^<n__^<b_Number of docking ports:_^>b_ 5_^<n__^<b_Number of private compartments:_^>b_ 2_^<n__^<g__^<b_Note:_^>b_ The retired Salyut 7, unused after 1986, remained in orbit until 1991, when it burned up while reentering the atmosphere._^<g_
_^<n__^<a!T549_aircraft_^>a__^<n__^<a!T550_aircraft, military_^>a__^<n__^<a!T561_airship_^>a__^<n__^<a!T2331_aviation_^>a__^<n__^<a!T12339_Fokker, Anthony Hermann Gerard_^>a__^<n__^<a!T12340_Fokker D-VII_^>a__^<n__^<a!T13522_Germany, history of_^>a__^<n__^<a!T14083_Gotha (aircraft)_^>a__^<n__^<a!T27713_Richthofen, Manfred, Freiherr von_^>a__^<n__^<a!T27714_Rickenbacker, Eddie_^>a__^<n__^<a!T30443_Sopwith Camel_^>a__^<n__^<a!T30554_SPAD_^>a__^<n__^<a!T35394_World War I_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D39540_--Aviation_^>a__^<n__^<a!D42230_----The Birth of Flight_^>a__^<n__^<b_----WW I_^>b__^<n__^<a!D36478_----The Golden Age_^>a__^<n__^<a!D38097_----Air Power in WW II_^>a__^<n__^<a!D38521_----The Jet Age_^>a__^<n__^<a!D38640_----New Horizons_^>a__^<n__^<a!D38734_----Principles of Flight_^>a__^<n__^<g_
_^<b_Pictures_^>b__^<n__^<a!P47367_Boeing, William Edward_^>a__^<n__^<a!P47581_Curtiss Jenny_^>a__^<n__^<a!P48037_Ford Trimotor_^>a__^<n__^<a!P48506_Hughes, Howard_^>a__^<n__^<a!P48756_Piper Cub_^>a__^<n__^<a!P45027_R-34 at Mineola, NY_^>a__^<n__^<g_
_^<n__^<a!T549_aircraft_^>a__^<n__^<a!T561_airship_^>a__^<n__^<a!T2331_aviation_^>a__^<n__^<a!T2816_barnstorming_^>a__^<n__^<a!T4106_Boeing, William Edward_^>a__^<n__^<a!T5330_Byrd, Richard E._^>a__^<n__^<a!T8708_Curtiss Jenny_^>a__^<n__^<a!T9124_DC-3_^>a__^<n__^<a!T10473_Earhart, Amelia_^>a__^<n__^<a!T12433_Ford Trimotor_^>a__^<n__^<a!T15814_Hindenburg_^>a__^<n__^<a!T16342_Hughes, Howard_^>a__^<n__^<a!T19745_Lindbergh, Charles A._^>a__^<n__^<a!T26360_postal services_^>a__^<n__^<a!T35812_Zeppelin, Ferdinand, Graf von_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D39540_--Aviation_^>a__^<n__^<a!D42230_----The Birth of Flight_^>a__^<n__^<a!D48582_----WW I_^>a__^<n__^<b_----The Golden Age_^>b__^<n__^<a!D38097_----Air Power in WW II_^>a__^<n__^<a!D38521_----The Jet Age_^>a__^<n__^<a!D38640_----New Horizons_^>a__^<n__^<a!D38734_----Principles of Flight_^>a__^<n__^<g_
_^<n__^<a!T549_aircraft_^>a__^<n__^<a!T550_aircraft, military_^>a__^<n__^<a!T1996_Asia, history of (II)_^>a__^<n__^<a!T2331_aviation_^>a__^<n__^<a!T2402_B-29 Superfortress_^>a__^<n__^<a!T2403_B-52 Stratofortress_^>a__^<n__^<a!T3958_blitzkrieg_^>a__^<n__^<a!T4776_Britain, Battle of_^>a__^<n__^<a!T8207_Corsair (aircraft)_^>a__^<n__^<a!T10145_Dresden_^>a__^<n__^<a!T11397_Europe, history of (I)_^>a__^<n__^<a!T13522_Germany, history of_^>a__^<n__^<a!T14569_Grumman, Leroy_^>a__^<n__^<a!T16460_Hurricane (aircraft)_^>a__^<n__^<a!T21739_Messerschmitt Bf-109_^>a__^<n__^<a!T21926_Midway, Battle of_^>a__^<n__^<a!T22950_Mustang (aircraft)_^>a__^<n__^<a!T24710_P-38 Lightning_^>a__^<n__^<a!T24711_P-40_^>a__^<n__^<a!T27079_radar_^>a__^<n__^<a!T30702_Spitfire_^>a__^<n__^<a!T31263_Stuka_^>a__^<n__^<a!T35397_World War II_^>a__^<n__^<a!T35814_Zero (aircraft)_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D39540_--Aviation_^>a__^<n__^<a!D42230_----The Birth of Flight_^>a__^<n__^<a!D48582_----WW I_^>a__^<n__^<a!D36478_----The Golden Age_^>a__^<n__^<b_----Air Power in WW II_^>b__^<n__^<a!D38521_----The Jet Age_^>a__^<n__^<a!D38640_----New Horizons_^>a__^<n__^<a!D38734_----Principles of Flight_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D39540_--Aviation_^>a__^<n__^<a!D42230_----The Birth of Flight_^>a__^<n__^<a!D48582_----WW I_^>a__^<n__^<a!D36478_----The Golden Age_^>a__^<n__^<a!D38097_----Air Power in WW II_^>a__^<n__^<b_----The Jet Age_^>b__^<n__^<a!D38640_----New Horizons_^>a__^<n__^<a!D38734_----Principles of Flight_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D39540_--Aviation_^>a__^<n__^<a!D42230_----The Birth of Flight_^>a__^<n__^<a!D48582_----WW I_^>a__^<n__^<a!D36478_----The Golden Age_^>a__^<n__^<a!D38097_----Air Power in WW II_^>a__^<n__^<a!D38521_----The Jet Age_^>a__^<n__^<b_----New Horizons_^>b__^<n__^<a!D38734_----Principles of Flight_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D39540_--Aviation_^>a__^<n__^<a!D42230_----The Birth of Flight_^>a__^<n__^<a!D48582_----WW I_^>a__^<n__^<a!D36478_----The Golden Age_^>a__^<n__^<a!D38097_----Air Power in WW II_^>a__^<n__^<a!D38521_----The Jet Age_^>a__^<n__^<a!D38640_----New Horizons_^>a__^<n__^<b_----Principles of Flight_^>b__^<n__^<g_
_^<n__^<a!T2331_aviation_^>a__^<n__^<a!T549_aircraft_^>a__^<n__^<a!T2621_balloon_^>a__^<n__^<a!T3943_Bleriot, Louis_^>a__^<n__^<a!T6546_Chanute, Octave_^>a__^<n__^<a!T7213_Civil War, U.S._^>a__^<n__^<a!T8707_Curtiss, Glenn Hammond_^>a__^<n__^<a!T12245_flight_^>a__^<n__^<a!T12651_Franco-Prussian War_^>a__^<n__^<a!T12805_French Revolution_^>a__^<n__^<a!T13796_glider_^>a__^<n__^<a!T19694_Lilienthal, Otto_^>a__^<n__^<a!T22449_Montgolfier brothers_^>a__^<n__^<a!T35439_Wright, Orville and Wilbur_^>a__^<n__^<g_
_^<n__^<a!D36046_Interactivities_^>a__^<n__^<a!D39540_--Aviation_^>a__^<n__^<b_----The Birth of Flight_^>b__^<n__^<a!D48582_----WW I_^>a__^<n__^<a!D36478_----The Golden Age_^>a__^<n__^<a!D38097_----Air Power in WW II_^>a__^<n__^<a!D38521_----The Jet Age_^>a__^<n__^<a!D38640_----New Horizons_^>a__^<n__^<a!D38734_----Principles of Flight_^>a__^<n__^<g_
Assistant Professor History, United States Military Academy, West Point, N.Y._^<g_
School of Business Administration, University of Virginia, Charlottesville._^<g_
Former Head of Department of Biotechnology, Institute for Industrial Research and Standards, Dublin, Ireland._^<g_
Assistant Professor of Clinical Medicine, College of Physicians and Surgeons, Columbia University, New York, N.Y._^<g_
Professor of Sociology, University of California, San Diego._^<g_
University Veterinarian, Rutgers University, Piscataway, N.J._^<g_
National Institute of Standards and Technology, Boulder, Colo._^<g_
Professor of Law, University of Illinois, Champaign._^<g_
Associate Professor of Medicine, Division of Endocrinology, Yale University School of Medicine, New Haven, Conn._^<g_
Research Associate Scientist, Institute of Arctic and Alpine Research, University of Colorado, Boulder._^<g_
Emeritus Professor of Psychiatry, Connecticut Mental Health Center, Yale University, New Haven, Conn._^<g_
Freelance Writer._^<g_
Staff Writer._^<g_
Freelance Writer._^<g_
Freelance Writer._^<g_
Staff Writer._^<g_
Freelance Writer._^<g_
Staff Writer._^<g_
Henry R. Luce Professor, College of the Holy Cross, Worcester, Mass._^<g_
Associate Professor, Department of Learning Resources and Technologies, Eastern Michigan University, Ypsilanti._^<g_
Department of Anthropology, University of California, Santa Barbara._^<g_
Associate Professor, Rush Medical College, Chicago, Ill._^<g_
Author of _^<i_Czechoslovak Armored Vehicles 1918-1945_^>i_, _^<i_Slovak Army 1939-1945_^>i_._^<g_
Senior Fellow, The Brookings Institution._^<g_
NASA Astronomical Data Center, Bethesda, Md._^<g_
Consultant in Forensic Medicine._^<g_
Professor of Architecture, The City College of New York, New York City._^<g_
Consultant to the Shipping Industry._^<g_
Brookhaven National Laboratory, Upton, N.Y._^<g_
Marine Resources Development Foundation, Key Largo, Fla._^<g_
Assistant Professor of Medicine, Director of Respiratory Care Services, University of Washington, Seattle._^<g_
Department of Ophthalmology, University of Florida Medical Center, Gainesville._^<g_
Research Assistant Professor, Department of Pharmacology and Toxicology, School of Medicine and Health Sciences, University of North Dakota, Grand Forks._^<g_
International Romani Union._^<g_
Consultant, Lecturer, and Writer; Emeritus Associate Professor, Washington University, St. Louis, Mo._^<g_
Department of Chemistry, James Madison University, Harrisonburg, Va._^<g_
Electron Microscope Facility, Clemson University, Clemson, S.C._^<g_
Professor, Department of Resource Economics, University of Massachusetts, Amherst._^<g_
Associate Professor, Department of Geography, University of Nevada, Reno._^<g_
Director of Body Imaging, South Nassau Communities Hospital, Oceanside, N.Y._^<g_
Associate Professor, Department of Health Policy and Administration, Pennsylvania State University, University Park._^<g_
Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, Ohio._^<g_
Sir Frederic C. Bartlett Professor of Psychology, University of Wisconsin, Madison._^<g_
Department of Psychology, Emory University, Atlanta, Ga._^<g_
Professor of Anthropology, Central Michigan University, Mount Pleasant._^<g_
Pulmonary Fellow, University of Washington Medical Center, University of Washington, Seattle._^<g_
Hawaii Institute of Geophysics and Planetology, University of Hawaii at Manoa, Honolulu, Hawaii._^<g_
_^<a!T7366_William Jefferson Clinton_^>a_, 51, was sworn in for his second term as _^<a!T26501_president of the United States _^>a_on Jan. 20, 1997, on the steps of the U.S. Capitol. In his Inaugural Address, he called for "a new sense of responsibility for a new century" and an end to the "politics of bickering." (Reuters/ Jim Bourg/Archive Photos)_^<g_
On Feb. 23, 1997, researchers at the Roslin Institute in Scotland reported the first successful _^<a!T7384_cloning_^>a_ of an adult animal-a Dorset _^<a!T29644_sheep_^>a_ named Dolly. Human cloning, still a far-off scientific prospect, became the subject of heated ethical debate among pundits, policy makers, and the general public. (Reuters/Ian Waldie/Archive Photos)_^<g_
The "_^<a!T7706_comet_^>a_ of the century," Hale- Bopp, made its closest approach to Earth (122 million miles) and its most dramatic appearance in March 1997. According to astronomers, the spectacular two-tailed "dirty snowball" had last appeared some 4,300 years before. (Associazone Astronomica Cortina)_^<g_
On May 13, 1997, Eldrick _^<a!T35335_"Tiger" Woods_^>a_-age 21-became the youngest player ever to win the Masters _^<a!T13970_Golf_^>a_ Tournament and the first black to win any major pro golf tournament. His 72-hole score of 270 (18 under par) set a Masters record, as did his margin of victory (12 strokes) over the second-place finisher. (Reuters/Gary Hershorn/Archive Photos)_^<g_
Thirty-nine members of a spiritual _^<a!T27483_cult_^>a_ called "Heaven's Gate" are found dead at their rented estate in Rancho Santa Fe, Calif. Written and videotaped messages reveal that their deaths are a mass-suicide for the purpose of achieving a "higher level of reality" and embarking on an alien spacecraft they believe is trailing the Comet Hale-Bopp._^<g_
Ending a four-month standoff, the Peruvian military on April 22, 1997, storms the Japanese ambassador's residence in Lima, where _^<a!T33168_Tupac Amaru _^>a_ guerrillas are still holding 72 hostages. One of the hostages is killed, the rest freed. Fourteen rebels and two soldiers also die in the raid._^<g_
In the California _^<a!T7203_civil trial_^>a_ of _^<a!T29956_O. J. Simpson_^>a_ for the stabbing deaths of his former wife, Nicole Brown Simpson, and her friend, Ronald Goldman, the jury finds the former football star liable. Damages total $33.5 million._^<g_
The British newspaper _^<i_Observer_^>i_ reports on Feb. 23, 1997, that a team of scientists in Edinburgh, Scotland, has created the first genetic _^<a!T7384_clone_^>a_ of an adult animal-a Dorset _^<a!T29644_sheep_^>a_ named Dolly._^<g_
_^<a!T35335_Tiger Woods_^>a_, 21, emerges as the new superstar of _^<a!T13970_golf _^>a_ by winning the Masters Tournament with a record 72-hole score of 270, or 18 under par._^<g_
_^<a!T9388_Deng Xiaoping_^>a_, the paramount leader of contemporary _^<a!T6872_China _^>a_ who survived purges in the 1960s and 1970s to lead his nation to sweeping capitalist reform, dies in Beijing on Feb. 19, 1997, at age 92._^<g_
On April 15, 1997, exactly 50 years after he trotted onto the field for his first game as a major leaguer-thereby breaking _^<a!T2900_baseball's_^>a_ long-standing barrier against African American players-_^<a!T27877_Jackie Robinson _^>a_ is remembered by the baseball community and the entire nation._^<g_
The disappearance of _^<a!T10473_Amelia Earhart_^>a_ has been the subject of unending theorizing, both well-meaning and malicious, serious and cinematic. Some believe that her Lockheed Elektra crashed in the sea; others contend that she was taken prisoner by Japan; and some believe that she is still alive today, on a tiny island somewhere in the Pacific._^<g_
_^<a!T10627_Thomas Edison's _^>a_"invention factory" from 1876 to 1886, the _^<a!T21629_Menlo Park_^>a_ (N.J.) Laboratory looked like an ordinary white farmhouse, measuring 100 ft long and 30 ft wide. Today, the site of the laboratory is marked by a 130-ft concrete tower, topped by a giant replica of Edison's original incandescent lamp._^<g_
More than 10 years elapsed between the time_^<a!T11723_ Philo T. Farnsworth_^>a_ demonstrated his first all-electronic_^<a!T32025_ television_^>a_ system and the launch of regular television service by the National Broadcasting Company-a subsidiary of RCA. Regular TV service began as part of the opening ceremonies for the New York World's Fair in April 1939._^<g_
The voice in this classic radio recording belonged to Herb Morrison of WLS, an NBC-Blue affiliate station in Chicago. Contrary to popular accounts, Morrison's commentary was not broadcast live. It was not aired until many hours after the _^<a!T15814_Hindenburg _^>a_explosion._^<g_
Of the 18 men who held the office of _^<a!T26501_president of the United States_^>a_ in the 20th century, none have had greater impact than the six shown in these videos: _^<a!T28033_Theodore Roosevelt_^>a_,_^<a!T35140_Woodrow Wilson_^>a_, _^<a!T28032_Franklin Roosevelt_^>a_, _^<a!T17694_Lyndon Johnson_^>a_, _^<a!T23737_Richard Nixon_^>a_, and _^<a!T27317_Ronald Reagan_^>a_. Whether by guiding the nation through tumultuous events, defining philosophies of government, or setting the moral tone, these are the leaders who shaped the American century. (A separate video selection is available for John F. Kennedy.)_^<g_
_^<a!T3709_Biological locomotion_^>a_ is the process-and study-of how animals move, a function as varied as the animal kingdom itself. The _^<a!T6172_caterpillar_^>a_, _^<a!T30229_snake_^>a_, _^<a!T10463_eagle_^>a_, _^<a!T18022_kangaroo_^>a_, _^<a!T6701_cheetah_^>a_, and _^<a!T13711_giraffe_^>a_ reflect the diversity of movements and physical features used by animals to hunt, evade predators, and achieve the basic motility needed to survive in their respective environments._^<g_
The encyclopedia articles _^<a!T8297_counterculture_^>a_ and _^<a!T34008_Vietnam War_^>a_ establish many of the themes you will encounter on this Guided Tour._^<g_
Before rummaging through the items in this Tour, take a few minutes to read the article on _^<a!T1511_antique collecting_^>a_._^<g_
An introduction to this fascinating subject is provided by three main articles in the encyclopedia: _^<a!T2827_baroque art and architecture_^>a_;_^<a!T2828_baroque literature_^>a_; and _^<a!T2829_baroque music_^>a_._^<g_
To get you in the right mood for this Tour, look over the articles _^<a!T7404_clown_^>a_ and _^<a!T7703_comedy_^>a_._^<g_
The article _^<a!T10589_economics_^>a_ provides a solid framework for this Tour's core discipline._^<g_
The articles _^<a!T11033_engineering_^>a_ and_^<a!T7202_civil engineering_^>a_ are good starting points for this Tour of the world's technological marvels._^<g_
The encyclopedia articles on _^<a!T30732_sports, history of_^>a_; _^<a!T22901_muscle_^>a_; and _^<a!T30053_skeleton, human_^>a_-as well as others you might find on your own-will help you enjoy this special Tour._^<g_
Before starting your excursion to Greece in the 5th century BC, peruse the article _^<a!T14336_Greece, ancient_^>a_._^<g_
Background reading on the great characters of world fiction can be found in the survey articles on _^<a!T19820_literature_^>a_; _^<a!T1094_American literature_^>a_; _^<a!T12802_French literature_^>a_; and others._^<g_
Overview articles on this important and exciting field include: _^<a!T21498_medicine_^>a_; _^<a!T21500_medicine, history of_^>a_; and _^<a!T21493_medical instrumentation_^>a_._^<g_
Prime yourself for this Tour by reading the background articles on _^<a!T24641_outlaws_^>a_ and _^<a!T26138_police_^>a_._^<g_
Take the article _^<a!T24987_Paris (France)_^>a_ as your point of departure for this trip to the "City of Light."_^<g_
The general survey article on _^<a!T26686_Protestantism_^>a_ provides a solid introduction to this broad subject._^<g_
Begin your exploration of "The Sea Around Us" by reading the encyclopedia articles _^<a!T24104_ocean and sea_^>a_ and _^<a!T24117_oceanography_^>a_._^<g_
Background information on the history, geography, peoples, and cultures of Spanish American can be found in the following articles: _^<a!T19144_Latin America, history of_^>a_; _^<a!T30482_South America_^>a_; and_^<a!T6345_Central America_^>a_._^<g_
Professor of Pediatrics, Univeristy of Texas Medical Branch, Galveston._^<g_
Associate Professor, Department of Religious Studies, Arizona State University, Tempe._^<g_
_^<b_GROLIER'S ONLINE KNOWLEDGE EXPLORER_^>b_ provides special Internet access to an unparalleled archive of in-depth, supplementary information on the subject of your choice._^<g_Up to four different sources may be listed in the Online Knowledge Explorer window. To gain access, simply select the one you are interested in and click the "Go Online" button at the bottom of the screen._^<g_Articles in the _^<b_Encyclopedia Americana_^>b_ provide more detailed and extensive information than the original article in _^<i_The Grolier Multimedia Encyclopedia_^>i_._^<g_Articles in _^<b_The New Book of Knowledge_^>b_ offer simpler, more general background than that found in _^<i_The Grolier Multimedia Encyclopedia_^>i_._^<g_The _^<b_Grolier Internet Index_^>b_ is a vast collection of World Wide Web sites that have been individually selected for their quality and depth, and then linked to individual _^<i_GME_^>i_ articles. The Index is refreshed and expanded every month. Follow the instructions on the Index pages for downloading updates._^<g__^<b_Article Updates_^>b_ gives you the latest revisions to articles in _^<i_The Grolier Multimedia Encyclopedia_^>i_. Many hundreds of articles are updated for important developments every month. Follow the instructions on the Update pages for downloading new lists of revised articles._^<g_ Editor's Note: You may discover that the factual details in the _^<i_Encyclopedia American_^>i_ or _^<i_The New Book of Knowledge_^>i_ sometimes differ from those in the _^<i_Grolier Multimedia Encyclopedia_^>i_, or from each other. These acclaimed reference works are independently researched and edited, relying on a broad variety of information sources. Some of the most reliable and authoritative reference materials differ in their assumptions and interpretations. "Facts" are not always what they seem!_^<g_
Department of Geography, University of Puerto Rico, Rio Piedras._^<g_
Department of Physiology, School of Medicine and Health Sciences, University of North Dakota, Grand Forks._^<g_
Registered dietitian and nutrition consultant._^<g_
Drue Heinz Professor of American Literature, Oxford University, Oxford, England._^<g_
Professor and Chair of Animal Behavior Program, Department of Psychology, Bucknell University, Lewisburg, Pa._^<g_
Department of Geography, University of Western Ontario, London._^<g_
Department of Archaeology, University of Cambridge, Cambridge, England._^<g_
Department of Anthropology, Harvard University, Cambridge, Mass._^<g_
Director, Center for Biofilm Engineering, Montana State University, Bozeman._^<g_
International Jugglers Association._^<g_
Author of _^<i_The Encyclopedia of Women's History in America_^>i_._^<g_
National Down Syndrome Congress, Atlanta, Ga._^<g_
Professor of Anthropology, University of Otago, Dunedin, New Zealand._^<g_
Professor of Psychology, Ohio State University, Columbus._^<g_
Instruments and Sensing Program, Office of Space Science, National Aeronautics and Space Administration, Washington, D.C._^<g_
Consultant Neurologist, Department of Neurology, Chelsea and Westminster Hospital, London, England._^<g_
Department of Medieval History, University of St. Andrews, St. Andrews, Fife, Scotland._^<g_
Associate Professor, Division of Epidemiology, University of Minnesota School of Public Health, Minneapolis._^<g_
Department of Chemistry and Biochemistry, University of California, Los Angeles._^<g_
Department of Geology, University of Tennessee, Knoxville._^<g_
Department of Archaeology, University of Cambridge, Cambridge, England._^<g_
Department of Anthropology, Southern Illinois University, Carbondale._^<g_
Press Director, Human Rights Watch, New York City._^<g_
Professor of History, University of New Mexico, Alburquerque._^<g_
Division of Clinical Microbiology, Mayo Clinic, Rochester, Minn._^<g_
McDonald Institute for Archaeological Research, University of Cambridge, Cambridge, England._^<g_
Department of Anthropology, University of Illinois, Urbana._^<g_
Associate Professor, Department of German, University of Wisconsin, Madison._^<g_
Professor of Anthropology, University of Rhode Island, Kingston._^<g_
Professor of Medical Ethics, The Kennedy Institute for Ethics, Georgetown University, Washington, D.C._^<g_
Freelance Writer._^<g_
School of History and Archaeology, University of Wales, Cardiff._^<g_
Oriental Institute, University of Chicago, Chicago, Ill._^<g_
Assistant Professor, Medicine and Anatomy and Cell Biology, College of Physicians and Surgeons, Columbia University, New York City._^<g_
Department of Biochemistry, Ohio State University, Columbus._^<g_
Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tenn._^<g_
Professor and Director of Graduate Studies, Indiana University, Bloomington, Ind._^<g_
Assistant Professor of Rabbinic Literature and History, Baltimore Hebrew University, Baltimore, Md._^<g_
Department of Biological Chemistry, University of California Medical School, Los Angeles._^<g_
Research Associate, Smithsonian Institution, Washington, D.C._^<g_
The Susan and Douglas Dillon Chief Librarian of the Oriental Division, The New York Public Library, New York City._^<g_
Director, Folk Art Institute, Museum of American Folk Art, New York City._^<g_
Artist and Photographer; Visiting Artist, Amherst College, Amherst, Mass._^<g_
Assistant Professor, Department of City and Regional Planning, University of North Carolina, Chapel Hill._^<g_
Department of Political Science, University of Iowa, Iowa City._^<g_
Curator of Asian Art, Phoenix Art Museum, Phoenix, Ariz._^<g_
Assistant Professor of Ethnomusicology, University of California, Los Angeles._^<g_
Interpreter, Everglades National Park, Homestead, Fla._^<g_
Program in Finnish Studies, Columbia University, New York City._^<g_
Curator, University of Colorado Museum, Boulder._^<g_
Lecturer, Department of Philosophy, Lake Forest College, Lake Forest, Ill._^<g_
Optical Physicist,The Center for Applied Optical Sciences, Department of Physics, Alabama A _^<o!E221_ M University, Normal._^<g_
Professor of Pharmacology,College of Physicians and Surgeons, Columbia University, New York City._^<g_
Institute of Environmental Medicine, New York University Medical Center, Tuxedo, N.Y._^<g_
Anderson Clinical Faculty Chair for Cancer Treatment and Research; Director, Sandra G. Davis Ovarian Cancer Program; Professor of Gynecologic Oncology; M.D. Anderson Cancer Center, Houston, Tex._^<g_
_^<a!T24786_Pakistan_^>a_'s February 3 elections return former (1990-93) Prime Minister _^<a!T29599_Nawaz Sharif_^>a_ to that post, replacing Benazhir _^<a!T3603_Bhutto_^>a_, who had been dismissed by President Farooq Leghari. Sharif's party, the Pakistan _^<a!T22943_Muslim League_^>a_, secures two thirds of the contested National Assembly seats, increasing Sharif's power relative to that of Leghari, who resigns shortly thereafter._^<g_
After modifying its platform to broaden its appeal, _^<a!T33448_Britain_^>a_'s _^<a!T18846_Labour party_^>a_ wins a landslide victory in May 1 _^<a!T25023_parliamentary_^>a_ elections. _^<a!T3888_Tony Blair_^>a_ replaces Prime Minister _^<a!T20746_John Major_^>a_, and 18 years of _^<a!T7945_Conservative_^>a_ rule is brought to an end._^<g_
Zaire's longtime president _^<a!T22217_Mobutu Sese Seko_^>a_ is swept from power on May 19, 1997. Rebel leader _^<a!T17945_Laurent Kabila_^>a_ becomes president and switches the country's name back to _^<a!T7884_Democratic Republic of Congo_^>a_._^<g_
_^<a!T12624_French_^>a_ voters take a surprising turn leftward after President _^<a!T6915_Jacques Chirac_^>a_ calls for the dissolution of parliament and early elections. The Socialists take 274 seats in the National Assembly, part of a left-coalition majority of 319 (vs. 242 for the conservative coalition). Socialist party leader _^<a!T17814_Lionel Jospin_^>a_ is named president on June 2._^<g_
At midnight on June 30, 1997, the colony of _^<a!T16063_Hong Kong_^>a_ reverts to Chinese sovereignty after 156 years of _^<a!T14297_British_^>a_ rule. Deemed a "Special Administrative Region" of _^<a!T6873_China_^>a_, Hong Kong is allowed to maintain some economic autonomy and political control._^<g_
_^<a!T9569_Diana, princess of Wales_^>a_, and Emad Mohamed (Dodi) al Fayed are killed in a high-speed car crash in Paris on Aug. 31, 1997. The immensely popular princess's televised funeral is watched by an audience estimated to exceed 1 billion worldwide._^<g_
Following financial disarray and a November bailout by the _^<a!T17025_International Monetary Fund_^>a_ (IMF), _^<a!T30492_South Korea_^>a_ elects veteran opposition leader _^<a!T18365_Kim Dae Jung_^>a_ of the National Congress for New Politics as its new president on Dec. 18, 1997, replacing _^<a!T18367_Kim Young Sam_^>a_._^<g_
_^<a!T17107_Iraq_^>a_ agrees to allow free access to _^<a!T33451_United Nations_^>a_ weapons inspectors charged with eliminating the nation's weapons of mass destruction. It is the first such document negotiated directly with Iraq's President _^<a!T16472_Saddam Hussein_^>a_. Iraq's Deputy Prime Minister Tariq Aziz expresses hope that the accord will lead to the removal of UN sanctions dating from the _^<a!T25491_Persian Gulf War_^>a_._^<g_
_^<a!T16799_India_^>a_'s president, K. R. Narayanan, asks Atal Behari Vajpayee of the right-wing _^<a!T3593_Bharatiya Janata party_^>a_ (B.J.P.) to form the nation's new government after the B.J.P. wins the highest number of parliamentary seats (though not a majority). The _^<a!T15818_Hindu_^>a_-nationalist B.J.P. softens its stance on religious issues to attract 19 coalition partners, necessary for it to run the government._^<g_
Hopes for an end to violence in _^<a!T23873_Northern Ireland_^>a_ are renewed by an April 10 peace agreement calling for cooperation between unionist Protestants and nationalist Catholics in running Northern Ireland. Negotiators included British Prime Minister _^<a!T3888_Tony Blair_^>a_, Irish Prime Minister _^<a!T505_Bertie Ahern_^>a_, former U.S. Senator _^<a!T22172_George Mitchell_^>a_, and the heads of eight other political factions. The deal must be confirmed by Northern Ireland and the _^<a!T17110_Irish Republic_^>a_._^<g_See also: _^<a!T17111_Ireland, history of_^>a_._^<g_
U.S. Army veteran Timothy McVeigh is convicted June 2, 1997 and sentenced to death for his role in the 1995 _^<a!T24240_bombing_^>a_ of the Alfred P. Murrah Federal Building in Oklahoma City, Okla., which had caused 168 deaths. On Dec. 23, 1997, Terry Nichols, who had served in the same unit as McVeigh, is convicted of conspiracy and involuntary manslaughter._^<g_See also: _^<a!T32140_terrorism_^>a_._^<g_
In June, the federal government and the U.S. _^<a!T32614_tobacco_^>a_ industry reach a negotiated settlement of lawsuits over the health hazards of smoking and the costs of tobacco-related illness. The settlement, which must be approved by Congress, would force the tobacco companies to pay $368.5 billion to plaintiffs over the next 25 years; accept limits on promotions and advertising; and pay fines if teenage _^<a!T30218_smoking_^>a_ fails to drop 60 percent over the next five years._^<g_
Suspected serial killer Andrew Cunanan shoots himself to death on a houseboat in Miami, Fla., on July 23, 1997. Cunanan is believed to have killed Italian fashion designer _^<a!T33900_Gianni Versace_^>a_ outside Versace's Miami Beach home on July 15._^<g_
A bipartisan bill requiring the balancing of the federal _^<a!T5065_budget_^>a_ by 2002 becomes law on Aug. 5, 1997. The agreement, a longtime Republican goal, emerges as Congressional Democrats and President Clinton accept Republican tax cuts in exchange for reduction of the welfare rolls._^<g_
Drivers for United Parcel Service (UPS) _^<a!T31213_strike_^>a_ over the company's replacement of permanent workers with benefits by multiple part-time workers without benefits, and over changes in pension administration. The strike, which hobbles the nation's business for 15 days, is a surprising, significant victory for the _^<a!T31971_Teamsters_^>a_ and organized _^<a!T18845_labor_^>a_._^<g_
The _^<a!T26650_Promise Keepers_^>a_ hold a march on the Mall in Washington, D.C., on Oct. 4, 1997. Hundreds of thousands of men go to atone for failures in their commitments to their families and communities. Fans of the Promise Keepers include the wives of members. Critics include feminists and _^<a!T12976_fundamentalist_^>a_ Protestant groups, who oppose the inclusive nature of Promise Keepers._^<g_
Bobbi McCaughey of Carlisle, Iowa, gives _^<a!T26475_birth_^>a_ to septuplets--three boys and four girls. McCaughey had taken _^<a!T11910_fertility_^>a_ treatments after she and husband Kenny were unable to conceive. The babies are two months _^<a!T26486_premature_^>a_, but all survive in relatively good health._^<g_See also: _^<a!T22802_multiple birth_^>a_._^<g_
_^<a!T26501_President_^>a_ _^<a!T7366_Bill Clinton_^>a_'s Second Inaugural takes place on Jan. 20, 1997, following Clinton's defeat of Republican Sen. _^<a!T9911_Bob Dole_^>a_ in national elections on Nov. 5, 1996._^<g_
Former White House intern Monica Lewinsky claims to have had a sexual relationship with the already scandal-plagued President _^<a!T7366_Clinton_^>a_. Lewinsky's allegations were secretly taped by her White House colleague Linda Tripp. Relentless media coverage of the sensational story draws attention from the central issues of _^<a!T16793_Independent Prosecutor_^>a_ Kenneth Starr's investigation of the alleged involvement of President Clinton in the _^<a!T34933_Whitewater affair_^>a_._^<g_
Four students and a teacher are shot dead, and 10 students are injured, by two boys aged 11 and 13 outside Westside Middle School in Jonesboro, Ark., on March 24, 1998. The killings shock the quiet Arkansas town and draw national attention to the problem of violence in schools._^<g_See also: _^<a!T16034_homicide_^>a_; _^<a!T33461_United States, education in the_^>a_._^<g_
International Business Machines (IBM) Corp.'s _^<a!T7785_computer_^>a_ Deep Blue defeats Russian chess grandmaster _^<a!T18095_Gary Kasparov_^>a_, 3 1/2 games to 2 1/2, in a six-game rematch in New York. Kasparov had defeated Deep Blue 4-2 in 1996._^<g_
The U.S. Mars Pathfinder lands in _^<a!T21117_Mars_^>a_'s Ares Vallis on July 4, 1997. With the help of its roving robotic explorer Sojourner, Pathfinder will transmit to Earth 16,000 images of Mars and 15 chemical analyses of its rocks and soil._^<g_See also: _^<a!T30541_space exploration_^>a_._^<g_
_^<a!T21775_Meteorologists_^>a_ meet in Geneva, Switzerland, to discuss potentially threatening weather conditions stemming from an _^<a!T10749_El Ni_^<o!E198_o_^>a_ ocean current expected off the northern coast of _^<a!T25513_Peru_^>a_ in early 1998. Temperature increases, flooding, and droughts across several continents are blamed on the phenomenon._^<g_
After defeating the heavily favored Atlanta Braves in the National League Championship Series, the Florida Marlins go on to defeat the Baltimore Orioles in seven games to win Major League _^<a!T2900_Baseball_^>a_'s World Series._^<g_
At the United Nations Climate Change Conference, held in _^<a!T18790_Kyoto_^>a_, Japan, Dec. 1-11, 1997, the United States, Japan, and European countries agree to cut emissions of carbon dioxide and other greenhouse gases by 2012. Developing nations, including China and India, are not subject to strict limits under the proposed treaty._^<g_See also: _^<a!T14386_greenhouse effect_^>a_._^<g_
The National _^<a!T12401_Football_^>a_ League's Denver Broncos, previously four-time Super Bowl losers, defeat the defending champion Green Bay Packers in Super Bowl XXXII, 31-24._^<g_
Germany wins the most medals (29) and the most gold medals (12) at the 1998 Winter _^<a!T24312_Olympic Games_^>a_ in _^<a!T23030_Nagano_^>a_, Japan, Feb. 7-22, 1998._^<g_
_^<a!T5570_James Cameron_^>a_'s 3 1/2-hour, $200 million epic _^<a!T12012_film_^>a_ _^<i__^<a!T32572_Titanic_^>a__^>i_, starring Leonardo DiCaprio and Kate Winslet, wins a record-tying 11 _^<a!T139_Oscars_^>a_, including Best Picture and Best Director. The film has grossed over $1 billion worldwide._^<g_
The $48 million _^<a!T12681_Franklin Delano Roosevelt Memorial_^>a_, designed by _^<a!T14918_Lawrence Halprin_^>a_, is dedicated on the Mall in Washington, DC, on May 2, 1997. The monument had been the subject of controversy over how the disabled president, who had poliomyelitis, should be represented._^<g_See also: _^<a!T28032_Roosevelt, Franklin Delano_^>a_._^<g_
_^<a!T31038_Jimmy Stewart_^>a_, star of more than 80 movies, dies on July 2, 1997 at age 89. Best known for his role as George Bailey in Frank Capra's _^<i__^<a!T17259_It's a Wonderful Life_^>a__^>i_ (1946), Stewart's tremendous popularity stemmed from his ability to portray a mythical small-town decency and earnestness._^<g_
The 125th anniversary celebration of _^<a!T35613_Yellowstone National Park_^>a_, titled "125 Years of the Best Idea America Ever Had," includes a retrospective of _^<a!T22519_Thomas Moran_^>a_'s 19th-century paintings of the Yellowstone area. Moran's paintings contributed to the popularity of the area and helped bring about its designation as a _^<a!T23216_national park_^>a_._^<g_
_^<a!T32115_Mother Teresa_^>a_, whose Missionaries of Charity serve the "poorest of the poor," dies in Calcutta at the age of 87. Her work among the destitute dying brought her the _^<a!T23751_Nobel Peace Prize_^>a_ and the Presidential Medal of Freedom._^<g_
One day after the 50th anniversary of _^<a!T35590_Chuck Yeager_^>a_'s pioneering supersonic flight, the British duo of Richard Noble and Andy Green break the _^<a!T30468_sound barrier_^>a_ with a _^<a!T17555_jet-powered_^>a_ car, the Thrust SSC, reaching a speed of 766.109 mph on Oct. 15, 1997._^<g_
In anticipation of the first-ever visit to communist _^<a!T8611_Cuba_^>a_ by _^<a!T17651_Pope John Paul II_^>a_, President _^<a!T6135_Fidel Castro_^>a_ allows legal celebrations of _^<a!T7023_Christmas_^>a_ for the first time in more than three decades. The pontiff had asked Castro to restore Christmas when the Cuban leader visited the Vatican in November 1996._^<g_
_^<a!T30713_Dr. Benjamin Spock_^>a_, whose _^<i_Dr. Spock's Baby and Child Care_^>i_ taught millions how to raise their _^<a!T6841_children_^>a_, dies on Mar. 16, 1998. Known as _^<i_The Commonsense Book of Baby and Child Care_^>i_ when it was first published (1946), Spock's book encouraged more leniency than was customary at the time. Spock was involved with several anti-war groups later in his life._^<g_
As the United States's bull _^<a!T31080_market_^>a_ endures longer than most observers believed possible, the _^<a!T10076_Dow Jones Industrial Average_^>a_ breaks milestone after milestone, topping 9000 on Apr. 6, 1998._^<g_
Thirty years after his assassination in Memphis, _^<a!T7205_civil rights_^>a_ leader _^<a!T18389_Martin Luther King, Jr._^>a_ is memorialized (Jan. 19, 1998) at the Ebenezer Baptist Church in Atlanta, where he had served as copastor with his father. James Earl Ray, convicted of King's murder but thought by some to be part of a conspiracy, died Apr. 23, 1998._^<g_
From January 1997 through April 1998, records were set on Wall Street, where stock prices soared; in _^<a!T23030_Nagano_^>a_, Japan, site of the 1998 Winter Olympics; and at the box-office, where _^<i__^<a!T32572_Titanic_^>a__^>i_ became the top-grossing film of all time. There were plenty of new weather records, too, as the phenomenon called _^<a!T10749_El Ni_^<o!E198_o_^>a_ brought storms and generally weird weather to many parts of the world._^<g_In Washington, D.C., the storm clouds were figurative--clouds of scandal, which dogged President _^<a!T7366_Bill Clinton_^>a_ in his second term despite accomplishments that included a proposal for the first balanced federal budget since 1969. Internationally, a financial crisis in Asia prompted worldwide concern._^<g__^<b__^<p_U.S. Developments: Whitewater and Wall Street_^>p__^>b__^<g_After nearly 30 years of staggering deficits, a balanced _^<a!T5065_budget_^>a_ was within reach for the U.S. government. In July 1997, Clinton and Congress agreed on a plan to balance the budget by 2002. Clinton moved the date up with his $1.73-trillion budget for fiscal year 1999, which forecast a surplus of $9.5 billion. Debate immediately broke out over how to spend the surplus. However, the budget depended on revenues that were to be obtained by closing tax loopholes and raising cigarette taxes, and it was not clear that Congress would do either._^<g__^<a!T7890_Congress_^>a_ also seemed unprepared to revamp widely criticized regulations governing contributions to _^<a!T5589_political campaigns_^>a_. While Capitol Hill hearings into alleged campaign finance abuses continued through 1997, House Speaker _^<a!T13690_Newt Gingrich_^>a_ orchestrated Republican opposition that kept a reform bill from coming to a vote._^<g_Increasingly, these and other domestic issues were overshadowed by a cloud of controversy around the White House. Independent counsel Kenneth W. Starr cast an ever-widening net in his investigation of President Clinton and first lady _^<a!T7367_Hillary Rodham Clinton_^>a_. Appointed in 1994 to probe the Clintons' involvement in _^<a!T34933_Whitewater_^>a_, a 1980s Arkansas real estate venture, Starr by 1998 was also pursuing allegations that the Clintons had hidden records and urged associates to keep silent about Whitewater and other matters._^<g_Meanwhile, intense publicity focused on a _^<a!T29528_sexual-harassment_^>a_ lawsuit brought by Paula Jones, an Arkansas woman who said Clinton had made an unwelcome sexual advance to her in 1991, while he was governor of Arkansas. The suit was thrown out, but not before the president gave a sworn deposition in which he denied, among other things, rumors that he had had an affair with Monica Lewinsky, a 21-year-old White House intern. Although Lewinsky also denied the rumors under oath, she said otherwise to friends--and Starr opened a fresh investigation to determine if the president had lied under oath and urged Lewinsky to do the same._^<g_Neither Whitewater nor rumors about Clinton's sex life damaged his popularity--in fact, polls showed his approval rating rising to new heights. Many Americans voiced impatience with the investigations and with the extensive media coverage they received. In fact, Americans had much to be happy about. Economic growth continued at a healthy rate. _^<a!T10977_Unemployment_^>a_ was low, and _^<a!T16882_inflation_^>a_ was nowhere to be found. And the _^<a!T31080_stock market_^>a_ continued its march to dizzying new heights. In April 1998, the _^<a!T10076_Dow Jones average_^>a_ topped 9,000 for the first time._^<g__^<b__^<p_Worldwide: Asian Flu_^>p__^>b__^<g_An economic crisis that erupted in East Asia was enough to give even the most bullish investors the jitters. Through the 1980s, the export-driven success of "Asian tigers" such as _^<a!T29973_Singapore_^>a_ and _^<a!T30492_South Korea_^>a_ had been the envy of the world. Foreign investment poured into these nations, financing everything from airports to skyscrapers. In 1997 the effects of too much spending and too much borrowing hit home._^<g_The trouble started in _^<a!T32195_Thailand_^>a_ in July, when an economic slowdown triggered a speculative run on the nation's currency. The government was forced to devalue the currency, and suddenly banks and businesses couldn't repay loans obtained in dollars and yen. The trouble rippled out to other nations as foreign investors, spooked, began to pull out, sending Asian currencies and stock markets into a tailspin. The _^<a!T17025_International Monetary Fund_^>a_ (IMF) came to the rescue in the worst cases--_^<a!T16839_Indonesia_^>a_ and South Korea, as well as Thailand--with loans and reform measures aimed at curbing the practices that led to the crisis. Economists forecast a long recession for the region._^<g_Asia's economic crisis unfolded just as the territory of _^<a!T16063_Hong Kong_^>a_ began to adjust to Chinese rule. Governed by Britain for more than 150 years, Hong Kong was formally returned to China on July 1, 1997. While China's Communist rulers promised to maintain Hong Kong's capitalist system for at least 50 years, many people worried that limits on free speech and other restrictions would soon change its way of life._^<g_In the _^<a!T21900_Middle East_^>a_, a series of confrontations between _^<a!T17107_Iraq_^>a_ and the _^<a!T33451_United Nations_^>a_ raised fears of new fighting in the _^<a!T25490_Persian Gulf_^>a_ region. The agreement ending the _^<a!T25491_Persian Gulf War_^>a_ of 1991 stipulated, among other things, that Iraq would not make or stockpile chemical, biological, or nuclear weapons--but U.N. inspection teams sent to follow up on that provision were repeatedly hindered. In November 1997 and again in February 1998, Iraqi obstructions brought inspections to a halt and prompted the United States to threaten retaliatory attacks. Last-minute diplomatic efforts allowed the inspections to go forward each time, but many observers expected more such incidents._^<g_The year 1998 was a special one for _^<a!T17231_Israel_^>a_--the 50th anniversary of its founding as a homeland for the Jewish people. Israelis could take pride in the remarkable success of their country. But the anniversary also signaled the 50th year of conflict between Israelis and Palestinian Arabs, displaced when Israel was created. Under past agreements, Palestinians had achieved a measure of self-rule in the _^<a!T34795_West Bank_^>a_ and the _^<a!T13325_Gaza Strip_^>a_ territories Israel had occupied since 1967. But with negotiations suspended for much of 1997, the peace process that led to those agreements was stalled. Militant Islamic groups continued to stage terrorist attacks, including several deadly suicide bombings in Jerusalem._^<g_Terrorism haunted North Africa as well. In _^<a!T806_Algeria_^>a_, where Islamic extremists had been waging a campaign of terror since 1991, violence reached new heights in 1997. Terrorist bands attacked villages, killing civilians by the score. In _^<a!T10685_Egypt_^>a_, Islamic terrorists targeted foreign tourists at the ancient Temple of Hatshepsut, near Luxor, on November 17. Fifty-eight tourists, four Egyptians, and six terrorists died in the assault._^<g_Farther south in Africa, _^<a!T22217_Mobutu Sese Seko_^>a_, who had ruled Zaire since 1965, was driven from power by a rebel group in May 1997; he died in exile in the fall. The rebel leader who ousted him, _^<a!T17945_Laurent Kabila_^>a_, declared himself head of state and changed the country's name to the _^<a!T7884_Democratic Republic of Congo_^>a_. Although Kabila denied it, there was evidence that his soldiers had murdered hundreds of refugees on their way to victory, mostly members of the Hutu ethnic group._^<g_In 1994, ethnic violence in this region had reached genocidal proportions, when _^<a!T16489_Hutus_^>a_ in _^<a!T28329_Rwanda_^>a_ killed an estimated half million _^<a!T33237_Tutsi_^>a_ civilians. In 1998 that violence was being examined by one of two U.N. war-crimes tribunals--the first such tribunals since the World War II era. The other tribunal was investigating reports of genocidal crimes in Bosnia, torn by ethnic fighting in the mid-1990s. In April 1998, as _^<a!T4353_Bosnia_^>a_ struggled to hold onto a fragile negotiated peace, new violence broke out in neighboring _^<a!T29427_Serbia_^>a_. The government there cracked down brutally on rebellious ethnic Albanians in the province of _^<a!T18630_Kosovo_^>a_._^<g__^<a!T28284_Russia_^>a_ continued to struggle with economic and political woes that were the legacy of the collapse of Communism. In predictably unpredictable fashion, Russian President _^<a!T35617_Boris Yeltsin_^>a_ fired his entire cabinet in March 1998. His new choice for premier--Sergei Kiriyenko, a virtually unknown 35-year-old--barely won confirmation in the legislature. Meanwhile, the _^<a!T23844_North Atlantic Treaty Organization_^>a_ (NATO), formed after World War II to defend Europe from the threat of the Soviet Union and its Eastern European allies, invited several of its former enemies--_^<a!T26118_Poland_^>a_, _^<a!T16414_Hungary_^>a_, and the _^<a!T8812_Czech Republic_^>a_--to become members. By expanding its membership, the alliance recognized a new mission: ensuring stability in Europe._^<g_In _^<a!T14296_Great Britain_^>a_, the _^<a!T18846_Labour party_^>a_ was in power for the first time in 18 years, after defeating the _^<a!T7945_Conservative party_^>a_ in general elections on May 1, 1997. _^<a!T3888_Tony Blair_^>a_, the 43-year-old Labour party leader, replaced Conservative _^<a!T20746_John Major_^>a_ as prime minister. One of Blair's priorities was to revitalize negotiations over _^<a!T23873_Northern Ireland_^>a_, which since the 1960s had been torn by violence between Irish Catholic nationalists and Protestants who support continued British rule. In April 1998 the parties reached a landmark agreement calling for a referendum on the future of the province._^<g_Two deaths touched the hearts of people around the world in 1997. Some 2.5 billion people worldwide watched the televised funeral of _^<a!T9569_Diana, Princess of Wales_^>a_, who died in a Paris car crash on August 31. The former wife of Prince Charles, heir to the British throne, Diana was just 36. While the world was still mourning her, news came of the death of _^<a!T32115_Mother Teresa_^>a_ of Calcutta, the legendary Roman Catholic nun who devoted her life to helping the poor and sick of India. She died on September 5 at age 87._^<g__^<b__^<p_Science, Sports, and the Arts_^>p__^>b__^<g_On July 4, 1997, an unmanned U.S. spacecraft touched down on the surface of _^<a!T21117_Mars_^>a_ and released a little six-wheeled robotic vehicle. Over the weeks that followed, the _^<i_Mars Pathfinder_^>i_ beamed back close-up photos of the rocky surface, along with reams of data on winds, temperatures, soil composition, and more. Among other things, the findings confirmed the likelihood that floods of water once washed over vast areas of the Red Planet._^<g_Back on Earth, there were real-time floods to contend with. _^<a!T10749_El Ni_^<o!E198_o_^>a_, a weather phenomenon brought on by a warming of Pacific Ocean waters, made for a hard winter in many areas in 1997-98. In the United States, the West Coast was battered with devastating storms, and much of the South was drenched as well. Only the Northeast, which experienced one of the mildest winters on record, escaped unscathed._^<g_The gloom cast by El Ni_^<o!E198_o storms was at least partly dispelled by the spectacle of the 1998 Winter _^<a!T24312_Olympics_^>a_, held in _^<a!T23030_Nagano_^>a_, Japan. Germany topped the list of medal winners, with a total of 29. U.S. athletes took home 13 medals, among them the gold in the first-ever women's Olympic ice-hockey tournament. _^<a!T19783_Tara Lipinski_^>a_, 15, became the youngest athlete to capture the gold in women's figure skating. Japan won 10 medals and much praise for organizing the Games, which were plagued by uncooperative weather._^<g_The blockbuster film _^<i__^<a!T32572_Titanic_^>a__^>i_ was the entertainment event of 1997-98. A fictional love story set on the "unsinkable" ocean liner that went down in the Atlantic in 1912, the film had been roundly criticized for its $200-million cost. It more than redeemed itself with record-breaking box-office receipts that topped $1.2 billion by the time the _^<a!T139_Academy Awards_^>a_ were handed out in March 1998. To no one's surprise, the film captured 11 Oscars, including the award for best picture._^<g_
Spotlights and fireworks lit the sky over Victoria Harbor on the night of June 30, 1997, as a new era began for _^<a!T16063_Hong Kong_^>a_. At midnight the colony was returned to _^<a!T6872_Chinese_^>a_ sovereignty after 156 years of British rule. Unlike other places in the world during 1997-98, the transfer of power in Hong Kong was peaceful--and widely celebrated. (Andres Hernandez/Gamma Liaison)_^<g_
In a historic shift, _^<a!T14296_British_^>a_ voters gave the _^<a!T18846_Labour party_^>a_ a landslide victory in parliamentary elections on May 1, 1997. Eighteen years of _^<a!T7945_Conservative_^>a_ rule were ended, and _^<a!T3888_Tony Blair_^>a_, 43, became the nation's youngest prime minister since Lord Liverpool in 1812. (Reuters/Ian Waldie/Archive Photos)_^<g_
The former _^<a!T14548_Group of Seven_^>a_ industrial powers, renamed the Summit of Eight with the addition of _^<a!T28284_Russia_^>a_, held its annual meeting on world economic issues in Denver, Colo., June 20-22, 1997. Hosted by _^<a!T7366_President Clinton_^>a_, the group included the leaders of _^<a!T5638_Canada_^>a_, _^<a!T12624_France_^>a_, _^<a!T13521_Germany_^>a_, _^<a!T14296_Great Britain_^>a_, _^<a!T17253_Italy_^>a_, _^<a!T17427_Japan_^>a_, and Russia. (Cynthia Johnson/Gamma Liaison)_^<g_
Many Americans excused themselves from July Fourth parades and barbecues to watch the _^<i_Mars Pathfinder_^>i_ touch down on the Red Planet. A six-wheeled, remote-controlled, robotic rover named _^<i_Sojourner_^>i_ was deployed from _^<i_Pathfinder_^>i_ to gather geologic data and transmit photos--which were breathtaking. _^<i_See also_^>i_ _^<a!T21117_Mars_^>a_. (JPL/NASA/Gamma Liaison)_^<g_
People in Great Britain and throughout the world would always remember where they were when they heard the news: In the early morning of Aug. 31, 1997, _^<a!T9569_Diana, the Princess of Wales_^>a_, was killed in a car crash in Paris, France. Her warmth, beauty, and good works had made the 36-year-old former heir to the British throne one of the best-loved figures on the world scene. (Andrew Shaw/FSP/Gamma Liaison)_^<g_
_^<a!T32115_Mother Teresa_^>a_, the Roman Catholic nun who had devoted her life to helping the world's "unwanted, unloved, and uncared for," died on Sept. 5, 1997, at age 87. The 1979 _^<a!T23751_Nobel Peace Prize_^>a_ winner was buried in _^<a!T5458_Calcutta_^>a_, India, where she carried out her work and where she was revered as the "Saint of the Gutter." (Santosh Basak/Gamma Liaison)_^<g_
The six-year-old _^<a!T17005_International Campaign to Ban Landmines_^>a_ and its coordinator, Jody Williams of Putney, Vt., were named the _^<a!T23751_Nobel Peace Prize_^>a_ winners for 1997. They were cited by the Nobel Committee for starting "a process which in the space of a few years changed a ban on anti-personnel mines from a vision to a feasible reality." (Reuters/Archive Photos)_^<g_
_^<a!T6872_China_^>a_'s President and General Secretary of the Communist party _^<a!T17580_Jiang Zemin_^>a_ realized a long-held goal when he was received on an official state visit to the United States in late October. During his week-long stay, Jiang met with President Clinton at the White House, congressional leaders, and business executives. (Diana Walker/Gamma Liaison)_^<g_
For the first time since the Communist regime in _^<a!T8611_Cuba_^>a_ declared it an atheistic state, Christians in that country were allowed to celebrate _^<a!T7023_Christmas_^>a_ in 1997. _^<a!T17651_Pope John Paul II_^>a_ visited the island nation one month later, the first time ever by a Catholic pontiff. (Daniel Le Claire/Gamma Liaison)_^<g_
The Denver Broncos finally won a Super Bowl, upsetting the defending champion Green Bay Packers, 31-24, in Super Bowl XXXII on Jan. 25, 1998, in San Diego. For the Broncos and longtime star quarterback _^<a!T10930_John Elway_^>a_, success was sweet: the Broncos had lost four previous Super Bowls, Elway three. (Traver/Gamma Liaison)_^<g_
The XVIII _^<a!T24312_Olympic_^>a_ Winter Games were held in _^<a!T23030_Nagano_^>a_, Japan, Feb. 7-22, 1998. More than 2,400 athletes--the most ever for a Winter Olympics--from 72 countries and regions competed in 14 sports. The weather was less than ideal, but IOC President _^<a!T28624_Juan Antonio Samaranch_^>a_ called the Nagano event "the best Winter Games ever." (Agence France Presse/Corbis-Bettmann)_^<g_
A natural starting point for your investigation would be the article _^<a!T1695_archaeology_^>a_. Read it for general background, and enjoy the Tour!_^<g_
If you like to read, this Tour will be a favorite. We suggest you start with the articles _^<a!T3545_best-seller_^>a_ and _^<a!T1094_American literature_^>a_._^<g_
A general introduction to the world's second largest nation can be found in the articles _^<a!T5637_Canada (I)_^>a_, _^<a!T5638_Canada (II)_^>a_, and _^<a!T5639_Canada, history of_^>a_._^<g_
As you study the various terms and concepts in this glossary of American politics, you may want to consult such articles as _^<a!T14116_government_^>a_; _^<a!T9363_democracy_^>a_; and the three entries _^<a!T7979_Constitution of the United States (I)_^>a_, _^<a!T7980_(II)_^>a_, and _^<a!T7981_(III)_^>a_._^<g_
Anyone making a journey to the center of the earth--or around it--should take along some reading. Start with the articles _^<a!T10493_Earth sciences_^>a_; _^<a!T10490_Earth, structure and composition of_^>a_; and _^<a!T13438_geology_^>a_._^<g_
The articles _^<a!T27480_religion_^>a_ and _^<a!T1995_Asia, history of (I)_^>a_ and _^<a!T1996_(II)_^>a_ will introduce you to some of the challenging concepts you'll encounter on this Tour._^<g_
The articles _^<a!T486_agriculture, history of_^>a_ and _^<a!T25975_plant breeding_^>a_ provide in-depth background on the many uses of plants._^<g_
The articles _^<a!T11689_fantasy (literature)_^>a_ and _^<a!T10140_dreams and dreaming_^>a_ will set the tone for this mind-expanding journey. Read them before you leave!_^<g_
Among the survey articles that relate to the personalities assembled in this Tour are: _^<a!T212_acting_^>a_; _^<a!T2613_ballet_^>a_; _^<a!T12011_film, history of (I)_^>a_ and _^<a!T12012_(II)_^>a_; and _^<a!T24394_opera_^>a_._^<g_
Heading off to the Big Apple? Check out the article _^<a!T23513_New York (city)_^>a_, and have a great trip!_^<g_
What is modernism? First read the articles _^<a!T22236_modernism (in literature)_^>a_ and _^<a!T22231_modern art_^>a_...then take the Tour and try to come up with your own definition!_^<g_
No recommended reading for _^<i_this_^>i_ Tour! Organize a game with your friends, or learn the names yourself and stump your family (probably your teacher too!)._^<g_
Start your journey to the South Seas by reading the articles _^<a!T24107_Oceania_^>a_ and _^<a!T24109_Oceania, art of_^>a_._^<g_
The articles _^<a!T11805_Federalist party_^>a_ and _^<a!T33462_United States, history of the (I)_^>a_ provide a good introduction to the creation of the American republic._^<g_
The main themes of this Tour, "Manifest Destiny" and the expansion of the United States, are broadly explored in the article _^<a!T33463_United States, history of the (II)_^>a_._^<g_
The 19th-century African American experience is surveyed in the following articles: _^<a!T399_African American history_^>a_; _^<a!T33463_United States, history of the (II)_^>a_; _^<a!T81_abolitionists_^>a_; and _^<a!T27348_Reconstruction_^>a_._^<g_
For an introduction to the themes of progressivism and imperialism around the turn of the 20th century, see the articles _^<a!T33463_United States, history of the (II)_^>a_; _^<a!T26631_Progressive party_^>a_; and _^<a!T30563_Spanish-American War_^>a_._^<g_
Essential materials on the Great Depression and America's role in World War II are furnished in the articles _^<a!T9422_Depression of the 1930s_^>a_; _^<a!T35397_World War II (Part 1)_^>a_ and _^<a!T35398_(Part 2)_^>a_; and _^<a!T33463_United States, history of the (II)_^>a_._^<g_
This Tour is just for fun, but before you pack your bags for the beaches or the slopes, browse the article _^<a!T32774_tourism_^>a_._^<g_
Viewed from space, the planet Earth may appear to be a placid peaceful blue marble. But on its surface, beneath its crust, and in its atmosphere lie forces of unfathomable power. From the more common occurrences of river _^<a!T12258_flooding_^>a_ and forest _^<a!T12069_fires_^>a_ to the dramatic fury of _^<a!T10497_earthquakes_^>a_, _^<a!T16461_hurricanes_^>a_, and _^<a!T32733_tornadoes_^>a_, the natural phenomena shown here provide vivid evidence of that power._^<g_
Great feats of engineering are often described in superlatives--the longest, the tallest, the biggest. When they were built, the _^<a!T4870_Brooklyn Bridge_^>a_, _^<a!T10973_Empire State Building_^>a_, and _^<a!T16099_Hoover Dam_^>a_ met those standards. Other structural marvels--such as the _^<a!T24877_Panama Canal_^>a_, _^<a!T32841_Trans-Alaska Pipeline_^>a_, and _^<a!T6537_Channel Tunnel_^>a_--stand out because of the geophysical obstacles they overcame. Each is unique, and all are monuments to modern civil engineering._^<g_
In a century of unprecedented violence and competition among political ideologies, a few men had extraordinary individual impact. For good or evil, the six men featured in these videos--_^<a!T19424_Vladimir Ilich Lenin_^>a_, _^<a!T15873_Adolf Hitler_^>a_, _^<a!T13171_Mahatma Gandhi_^>a_, _^<a!T20966_Mao Zedong_^>a_, _^<a!T14035_Mikhail Gorbachev_^>a_, and _^<a!T20876_Nelson Mandela_^>a_--effected political and social changes that extended far beyond the borders of their respective nations._^<g_
The second-largest nation on earth, _^<a!T5637_Canada_^>a_ is a land of diverse terrains, cultures, and lifestyles--from the rustic Atlantic Provinces in the east to the rugged Canadian _^<a!T27921_Rockies_^>a_ of the west; from _^<a!T11265_Inuit_^>a_ life on the frozen tundra to cosmopolitan life in French-speaking _^<a!T26984_Quebec_^>a_; from the industries of _^<a!T24370_Ontario_^>a_ to the great plains of the Prairie Provinces. (See also: _^<a!T665_Alberta_^>a_, _^<a!T4780_British Columbia_^>a_, _^<a!T20908_Manitoba_^>a_, _^<a!T23462_New Brunswick_^>a_, _^<a!T23548_Newfoundland_^>a_, _^<a!T23888_Northwest Territories_^>a_, _^<a!T23925_Nova Scotia_^>a_, _^<a!T26565_Prince Edward Island_^>a_, _^<a!T28850_Saskatchewan_^>a_, and _^<a!T35731_Yukon Territory_^>a_.)_^<g_
Every field of human endeavor has its heroes, and the world of athletics has more than its share. The six men and women presented here--_^<a!T32388_Jim Thorpe_^>a_, _^<a!T28307_Babe Ruth_^>a_, _^<a!T24668_Jesse Owens_^>a_, _^<a!T35756_Babe Didrikson Zaharias_^>a_, _^<a!T27877_Jackie Robinson_^>a_, and _^<a!T18385_Billie Jean King_^>a_--were the true superstars of their eras. Their prowess and character set higher standards in competition, raised their respective sports to new prominence, and broke new ground for racial and gender equality._^<g_
The liquid and solid _^<a!T371_aerosol_^>a_ particles that enter Earth's _^<a!T2138_atmosphere_^>a_ originate mainly in natural sources. These aerosols can have major effects on Earth's _^<a!T7358_climate_^>a_ as, for example, when a major _^<a!T34177_volcanic_^>a_ eruption injects great quantities of matter into the atmosphere. In the past century, an increasing proportion of the aerosols entering the atmosphere have come from vehicles and industrial processes. These compounds also appear to affect the climate, as well as other aspects of the _^<a!T11089_environment_^>a_. For example, chlorofluorocarbons (CFC), once used extensively as propellants, cause destruction of stratospheric _^<a!T24707_ozone_^>a_, leading to the formation of "ozone holes" in the upper atmosphere._^<g_
An _^<a!T537_air conditioning_^>a_ unit does not "add coolness" to the _^<a!T536_air_^>a_. It removes heat, which is taken from the air by the rapid expansion of a _^<a!T27425_refrigerant_^>a_ as it turns from a liquid to a gas. Small air conditioners are designed to cool individual rooms. Central air-conditioning systems are used to cool all the rooms in a building at the same time. Cool, filtered air comes out of ducts through vents in the ceilings and returns to the air conditioner through ducts that open near the floors._^<g_
A two-pan _^<a!T2564_balance_^>a_ has screw nuts fitted on both ends of the balance beam for initial centering of the pointer. A small rider weight, which slides along a scale or the beam, is used to obtain more accurate readings of mass. _^<a!T21239_Mass_^>a_ is the amount of matter in an object, whereas _^<a!T34685_weight_^>a_ is the measure of gravity's pull on an object. Since gravity varies at different places on Earth's surface, an object's weight also varies; its mass does not._^<g_
_^<a!T13332_Gears_^>a_ range in size from the minute toothed wheels used in watch movements to the large transmission gearing of ships, which converts the power produced by a high-speed turbine running at perhaps 15,000 revolutions per minute (rpm) to the low speed of the propeller shaft turning at about 150 rpm. A familiar use of gearing is power _^<a!T32873_transmission_^>a_ in automobiles. The engine, rotating at high speed, delivers power to the transmission, where gears reduce the speed at which the power is transmitted to the driveshaft. The differential gearing, which joins the driveshaft to the rear axles, accomplishes the final speed reduction. Thus the wheels rotate at a speed much lower than that at which the engine turns._^<g_
A derailleur enables a _^<a!T3623_bicycle_^>a_ rider to change _^<a!T13332_gears_^>a_ by shifting the chain from one sprocket to another. When riding on the level or downhill, a small rear-wheel sprocket is used for high _^<a!T30617_speed_^>a_. When going uphill, a large rear-wheel sprocket is used, resulting in less speed but more _^<a!T12417_force_^>a_. To change gears, the rider moves a lever, which is connected by a gearshift cable to a hinged parallelogram. The position of the parallelogram changes, the chain lifts to another sprocket, and the two jockey wheels move to take up or release slack chain. The number of gears on a bicycle equals the number of front sprockets multiplied by the number of rear sprockets. For example, a ten-speed bike has 2 front sprockets and 5 rear sprockets._^<g_
With the introduction of the _^<a!T26657_propane_^>a_ torch, _^<a!T4020_blowtorches_^>a_ have become less common. A propane torch has two basic parts: a canister filled with propane and a burner assembly. In the canister, the propane is in a liquid state because it is under pressure. When the control valve on the burner assembly is opened, propane is released through the nozzle. The reduction in pressure vaporizes the propane, which will burn readily as it mixes with air._^<g_
Water _^<a!T4141_boilers_^>a_ are used in industrial processes, to heat buildings, and to operate _^<a!T30923_steam engines_^>a_ and _^<a!T33177_turbines_^>a_ for electrical generating plants, locomotives, and ships. Energy is usually provided by the burning of a fossil fuel (coal, oil, or natural gas). Other fuels include wood, waste gases from industrial processes, solid wastes such as sawdust and bagasse (from sugarcane), and nuclear fission of a radioactive substance such as uranium-235._^<g_
_^<a!T4251_Bookbinding_^>a_ is done in a bookbindery, either as a handcraft or by power-driven machinery. The hand binder uses special leathers for the covers, and papers processed in the old way to be acid-free and stable. _^<a!T4240_Books_^>a_ are sewn with nylon thread or with the traditional unbleached linen thread. Adhesives may be modern polyvinyl acetate emulsions or made of wheat flour and animal glue. Even the technique for decorating the cover has changed little over the centuries: heated brass dies are pressed into the leather by hand, the impression is coated with sizing, gold leaf is applied to the impression, and the heated die is pressed in again to fix the gold._^<g_
A _^<a!T4578_brake_^>a_ is a mechanism for stopping or retarding the motion of a vehicle or the movement of a machine part. Its primary function is to absorb energy of motion. Most brakes depend on friction between surfaces to transform the energy of motion to heat, which then dissipates in the surroundings. In fluid brakes, fluid friction is used to absorb the energy of motion. Agitation of the fluid produces fluid frictional energy, which heats the fluid; the heat is removed by circulating the fluid through a heat exchanger._^<g_See also: _^<a!T16521_hydraulic systems_^>a_._^<g_
A variety of plant substances can be ground into _^<a!T12279_flour_^>a_: grass seeds such as wheat and rye, legumes and tubers, even such items as artichoke and kelp. _^<a!T4645_Bread_^>a_ may also be made from a mixture of several flours, and the recipe may or may not include _^<a!T35593_yeast_^>a_ or other leavening. Such ingredients as milk, eggs, honey, sugar, or nuts sometimes are added. The cooking can be done by frying, boiling, or steaming instead of baking._^<g_
_^<a!T5657_Canals_^>a_ provide valuable shortcuts on important trade routes. Many link major river basins and lakes, and others provide better access to rivers than the often silt-clogged river mouths and harbors. Canals often are classified by the size of vessel they can accommodate. Some small local canals may be able to float only 100- to 300-ton boats or small rafts of timber. At the other extreme are ship canals 7.6 m (25 ft) or more deep and capable of accommodating large seagoing vessels. Water-level canals, such as the _^<a!T31329_Suez Canal_^>a_, do not vary in height along their courses. Lock canals, which include most modern waterways, contain locks for raising and lowering boats along their courses._^<g_
Almost all beverage _^<a!T5706_cans_^>a_ made in the United States are made of _^<a!T968_aluminum_^>a_. _^<a!T27355_Recycling_^>a_ is a critical component of the industry, accounting for more than one-third of the supply of this metal. The Aluminum Association noted that 100.5 billion aluminum beverage cans were shipped in 1997. Of these, 66.8 billion_^<o!E110_66.5%_^<o!E110_were collected for recycling, a vast improvement over 25 years earlier, when only 15.4% of the cans were collected for recycling. During those same 25 years, another change took place: manufacturers significantly reduced the thickness of cans, reducing the amount of aluminum needed for each container. In 1972, 21.75 cans were made per pound of aluminum; by 1997, 32.57 cans were made per pound._^<g_
The lightest and most flexible Roman siege machine, used from about 200 BC to AD 400, threw 2.7-kg (6-lb) javelins. Shooting from a _^<a!T6156_catapult_^>a_ was the same as the shooting of a crossbow, using two horizontal arms, each with its own skein, instead of the bent bow. A rope on a windlass at the rear of the stock drew back the bowstring by means of a triggered hook, adding torsion to the skeins. Pulling a lanyard released the stored force against the butt of the javelin, throwing it about 460 m (500 yd)._^<g_
Geologists believe that more than 500 million years ago, during the _^<a!T5550_Cambrian Period_^>a_, six major continents were spread out along or near the equator. During the _^<a!T9524_Devonian Period_^>a_ (390-340 million years ago), the continents had begun to cluster as a result of _^<a!T8007_continental drift_^>a_. At the end of the _^<a!T25454_Permian Period_^>a_ (225 million years ago), a single supercontinent, Pangea, had formed and had begun to break apart. The new continents created by the fragmentation of Pangea continued to drift, leading to Earth's present geography._^<g_
_^<a!T9796_Distillation_^>a_ has been used for some 2,000 years to purify liquids and to extract perfumes and flavorings from plants. Today it is used in refining _^<a!T25570_petroleum_^>a_, manufacturing _^<a!T699_alcohol_^>a_, and purifying some industrial wastes. The equipment used for distilling is called a still. The simplest kind of still has two parts: a boiler, in which the liquid is heated and vaporized, and a condenser, in which the liquid is cooled and condensed. Industrial stills are much more complicated, but they work on the same basic principles._^<g_
A _^<a!T10170_drill_^>a__^<o!E110_whether powered by hand or _^<a!T20499_machine_^>a__^<o!E110_has three parts: a point, a body, and a shank. The actual cutting of a workpiece is done at the point. As the drill moves into the workpiece, the point cuts away small chips. The shank is at the driving end of the drill. Its main function is to transmit the torque necessary to rotate the drill and the force necessary to feed the drill into the workpiece. The center, and major, portion of a drill is the body. It often contains flutes that run from the point to the shank. Flutes are straight or helical channels through which the chips or cuttings from the bottom of the drilled hole move to the surface of the workpiece._^<g_
_^<a!T10830_Electroplating_^>a_ is done for many purposes and on every scale, from the refinishing of an antique silver candlestick to high-speed electrotinning, where tin is plated on strips of steel to produce the tinplate that goes into the manufacture of tin cans. Silver is plated on tableware for its bright, attractive appearance and because it is nontoxic. Gold is plated on jewelry for its attractive, nontarnishing finish, and on surfaces where its low electrical-contact resistance is desired. Steel is coated with various metals for protection against corrosion and wear. Chromium, which is hard and has a low coefficient of friction, is plated on cutting tools, dies, and rolls. Copper is often used as a preliminary coating that is overplated with other metals; it tends to smooth over defects in the substrate, and when mechanical finishing is needed it is much easier to buff than steel._^<g_
Passenger _^<a!T10861_elevators_^>a_ have wide, shallow cars with wide entrances, so that people can enter and leave quickly at each stop. The height, width, and depth of other types of elevators vary with their use. For example, hospitals generally have elevators with deep, narrow cars, used to carry stretchers, wheelchairs, and portable apparatuses from floor to floor. Elevators are made of standardized parts, with each complete installation engineered for the specific job. They are assembled at the job site._^<g_
Types of _^<a!T12080_fireworks_^>a_ include Roman candles, rocks, firecrackers, shells, and fountains. These vary in composition, arrangement of components, and casing, but the basic principal is the same. In all, the pyrotechnic effects are based on the combustion of a solid fuel by an oxygen-containing salt, usually a metal nitrate or chlorate._^<g_
_^<a!T12104_Fish farming_^>a_, or aquaculture, is believed to have originated in China several thousand years ago. It was also practiced in ancient Egypt; a bas-relief in an Egyptian tomb built about 2000 BC shows tilapia, an African food _^<a!T12099_fish_^>a_, being harvested in an artificial pond. Today, many countries practice fish farming. In the United States, aquaculture production is more than 318 million kg (700 million lb) per year. Catfish is the most popular farmed fish in the U.S., followed by crawfish, trout, salmon, and oysters._^<g_
A _^<a!T13262_gas mask_^>a_ consists of a facepiece and a canister. The facepiece, made of impervious material, has clear lenses to permit vision and an exhaust valve through which the exhaled air escapes. The canister, which purifies the incoming air, contains a filter to remove particles and a layer of activated charcoal or other material to eliminate dangerous gases. It is not possible to design a canister of a reasonable size that will protect against all gases. Thus, masks and canisters are designed to protect against expected agents. For instance, a mask designed to protect a solider in the field is different from a mask designed to be used in a fire-filled room where the oxygen content is too low to sustain life._^<g_
First developed about 1911 by _^<a!T28312_Sir Ernest Rutherford_^>a_ and _^<a!T13348_Hans Geiger_^>a_ in England, the _^<a!T13350_Geiger counter_^>a_ is used to indicate the presence of _^<a!T27092_nuclear radiation_^>a_. Prospectors use it to find uranium-rich ores, physicians to locate radioactive tracers administered to patients, and chemists to study chemical reactions. The ionization tube is filled with a gas such as neon. When a high-energy particle enters the tube, it knocks an electron out of a neon atom, leaving a positively charged neon ion. The electron moves to a positive electrode and the ion to a negative electrode. The buildup of electrons on the positive electrode causes a discharge, which provides an electrical pulse that is registered on a meter._^<g_
The basic ingredient of commercial _^<a!T13761_glass_^>a_ is _^<a!T29880_silica_^>a_ sand, which is composed of the mineral quartz, a compound of the elements silicon and oxygen. Lime and sodium carbonate (soda ash) are added to act as fluxing agents. That is, they lower the melting point of the materials. Other substances can be added to adapt glass for special uses. For instance, lead gives glassware a clear, sparkling beauty, and borax keeps it from expanding and cracking, so it can be placed over a direct flame without breaking._^<g_
The two basic types of _^<a!T14431_grenades_^>a_ are hand grenades, which are thrown by hand, and launched grenades, which are propelled by grenade launchers. Grenades are further classified as explosive or chemical. Explosive grenades, producing fragmentation or blast, are primarily for antipersonnel or antitank effect. Chemical grenades are for antipersonnel, harassing, incendiary, smoke-screening, or signaling purposes._^<g_
Grinding is used mostly in finishing metal workpieces. However, nonmetals such as glass, plastic, and ceramic also are ground. There are two types of grinding: rough machine grinding and precision machine grinding. Rough machine grinding quickly removes surplus material from workpieces in preparation for further manufacturing. Precision machine grinding is used in finishing parts to achieve precise dimensions and refined surface finishes._^<g_See also: _^<a!T20502_machine tools_^>a_._^<g_
Things that spin act differently from things that do not spin. When they spin, they show two unusual properties: gyroscopic _^<a!T16868_inertia_^>a_ and _^<a!T26463_precession_^>a_. Gyroscopic inertia means that the axle of a spinning _^<a!T14771_gyroscope_^>a_ always tends to point in the direction in which it is set. Precession is what keeps the top of the gyroscope's axle moving in a circle after it has been tipped away from a straight up-and-down position. Once the axle has been tipped, the force of gravity tends to tip it farther down. But the axle precesses sideways, at a right angle to the downward pull of gravity._^<g_
Although its origin is unknown, the _^<a!T19531_lever_^>a_ was almost certainly used in prehistoric times in digging sticks and other simple tools. By 1550 BC the lever was used in Egypt and India to raise water from shallow wells, to move heavy objects in construction, and in weighing machines such as the lever-balance. Later, the Greeks used the lever in war machines such as catapults, and in the lever-press for squeezing grape juice. The mathematical principle of the lever was known to Aristotle, and was rigorously proved by Archimedes in the 3rd century BC._^<g_
There are several kinds of _^<a!T19685_lightning_^>a_. A jagged flash of lightning is called streak lightning. Sometimes, as lightning seeks the path of least resistance, it forks out; this is forked lightning. Chain, or bead, lightning begins as a streak and ends up looking like a string of beads. St. Elmo's fire, seen as a glow on pointed objects such as church steeples and poles, forms when the negative electrical charges at the base of a cloud attract positive charges from the ground below. The positive charges accumulate on pointed objects and slowly discharge into the air. Ball lightning appears as a round glowing ball that floats along the ground or through the air._^<g_
The Yale _^<a!T19906_lock_^>a_ has a rotating cylindrical plug with pins of different lengths standing in a row along the cylinder's turning axis. The edge of a flat key is notched to depths that correspond to the length of the pins. The notches on the key, when inserted, raise all the pins to the same height. This frees the plug to turn in the cylinder and releases the locking bolt._^<g_
_^<a!T34643_Weaving_^>a_ is the interlacing of two sets of threads at right angles to each other to form a web of fabric. The _^<a!T20013_loom_^>a_ is the frame or machine on which the warp threads are held at even tension. The simple treadle loom may have been introduced into Europe as early as the 13th century and was widely used until the invention of automated looms during the 1800s. The treadle loom is still popular today among people who have taken up weaving as a handicraft._^<g_
_^<a!T20502_Machine tools_^>a_ are designed to cut, shape, or form metal. They evolved from hand tools used on wood, and had their beginnings in the Industrial Revolution largely in England more than 200 years ago. The first _^<a!T21978_milling_^>a_ machine was invented by Eli Whitney, an American inventor and manufacturer, in 1818. Today, milling machines are perhaps the most versatile of machine tools. They offer a wide variety of cuts, made possible by the variety of cutters available._^<g_
Unlike coal and other fossil fuels, nuclear fuel must be precisely fabricated. Most _^<a!T23960_nuclear reactors_^>a_ use small, dense pellets of uranium dioxide. The pellets are placed in tubes bundled together to form fuel elements. The part of the reactor vessel that houses the fuel elements is called the core. Also within the core are movable control rods, which control the rate of _^<a!T12125_fission_^>a_. To prevent an excess buildup of heat, a coolant is circulated through and out of the reactor. In addition to cooling the fuel elements, the coolant carries heat out of the reactor to a place where it can do work._^<g_
The word _^<a!T24925__^<i_paper_^>i__^>a_ comes from the word _^<a!T24940__^<i_papyrus_^>i__^>a_, a writing material made by pasting together thin slabs of the papyrus reed that grew in the Nile Valley of Egypt. The invention of paper is generally attributed to a Chinese court official, Cai Lun (Ts'ai Lun), in about AD 105. The materials used were pulp made from the bark of a mulberry tree and fibers from cloth and hemp. Knowledge of papermaking spread from China to Arabia and to Europe by the 12th century. The first paper mill in the United States was built in 1690 in Philadelphia._^<g_
_^<a!T10627_Thomas Edison_^>a_'s _^<a!T25703_phonograph_^>a_ was inspired by his experiments in high-speed Morse telegraphy and in making a better microphone for telephones. Several hundred tinfoil phonographs were sold in the year or two after Edison's 1877 demonstration of his invention, "for exhibition as a novelty." Edison then turned his full attention to the electric light, which occupied him for several years._^<g_
A cartridge consists of a metal case, called the casing, and an elongated metal projectile, called the bullet. The latter term derives from the French _^<i_boulette_^>i_, meaning "small ball," since early bullets were loose round metal balls. A good modern bullet completely seals the bore, or interior diameter of the barrel, after ignition of the propelling charge, so that the gases produced do not escape but are efficiently used to propel the bullet._^<g_See also: _^<a!T25906_pistol_^>a_; _^<a!T12071_firearms_^>a_._^<g_
Virtually every fruit, vegetable, and grain has been _^<a!T25975_bred_^>a_ into a number of varieties. Cucumbers and squash come in bush varieties as well as the more familiar vining types. Carrot varieties range from long thin forms to short stubby types. Peach, apricot, and fig trees have been bred to survive cold northern temperatures. Wheat and rye have been crossed to produce a high-protein hybrid grain called triticale. Corn has been selectively bred to produce high-yield, disease-resistant varieties far different from the crop's wild ancestors._^<g_See also: _^<a!T25973_plant_^>a_._^<g_
_^<a!T24572_Osmosis_^>a_ takes place in all living things. One example is the _^<a!T16371_human body_^>a_, wherein plasma, the clear liquid part of the _^<a!T3984_blood_^>a_, is always passing out of the blood vessels. Plasma moves through the selectively permeable walls of tiny blood vessels called capillaries. The capillary walls do not allow red blood cells, which make up most of the rest of the blood, to pass out of them. Plasma carries digested food and other materials to all the cells of the body. As plasma bathes the cells, materials they need diffuse there from the plasma. Waste materials leave the cells by osmosis._^<g_
The union of an egg cell and a sperm cell within the fallopian tube of a woman is called _^<a!T11912_fertilization_^>a_. The nuclei of the two cells merge, and the egg begins to divide. This cell division usually begins within a few hours of fertilization. During the early stages of its development, the organism is called an _^<a!T10946_embryo_^>a_. By the 14th week, it is called a fetus. Often, doctors divide the nine-month gestation period into three-month periods called trimesters. In the first trimester, the embryo develops all the basic organ systems of the body. In the second trimester, the fetus becomes ever more human looking, and the mother can begin to feel it move. In the third trimester, which ends with _^<a!T26475_birth_^>a_, the fetus grows rapidly in weight and size; it adds about 50 percent of its weight during this time._^<g_
Gravure is a _^<a!T26581_printing_^>a_ process that uses an image recessed in a metal plate rather than an image on a raised or flat surface. The image is etched as tiny cells; the deeper a cell, the more ink it carries and transfers to the paper. Thus, shallow cells produce light parts of an illustration and deep cells produce the dark areas. _^<a!T28131_Rotogravure_^>a_ is used mainly for long-run production of magazines._^<g_
_^<a!T26581_Printing_^>a_--the art and technology of rapidly reproducing multiple copies of images--had its beginnings in China in the 9th century. Word characters were carved in relief out of wood blocks and ink was applied to the raised characters, which were then pressed by hand against mulberry-bark paper. This was the earliest example of letterpress printing, though most historians credit Johann Gutenberg of Germany with the invention of _^<a!T19513_letterpress_^>a_ printing as we know it today. The first rotary letterpress, which could print both sides of the paper at one time and also print on a continuous roll instead of sheets, was invented by William Bullock of Philadelphia in 1865._^<g_See also: _^<a!T34644_web-fed press_^>a_._^<g_
_^<a!T26834_Pulleys_^>a_ are used to facilitate lifting a heavy object, or to make the point of application and the direction of the pulling _^<a!T12417_force_^>a_ more convenient. Pulleys have aided humans' muscular efforts at least since the 5th century BC, when the Greeks used pulleys on ships and in the theater. A pulley has a mechanical advantage equal to _^<i_w/p_^>i_, where _^<i_w_^>i_ is the weight lifted and _^<i_p_^>i_ is the force applied. In a pulley system, the mechanical advantage depends on the number of pulleys and how they are arranged._^<g_
If rays of color are _^<a!T27414_reflected_^>a_ only once within raindrops, a bright _^<a!T27155_rainbow_^>a_ called the primary rainbow is formed. The colors are always observed in the same order. Beginning with the outermost, or top, circle, the colors are red, orange, yellow, green, blue, indigo, and violet. Sometimes the rays of color are reflected twice within the raindrops. A fainter secondary rainbow is then produced along with the primary rainbow. In the secondary rainbow the colors are reversed--the outermost circle is violet, and the colors are seen in reverse order to the innermost circle, which is red._^<g_
Threshed grains of _^<a!T27661_rice_^>a_, called rough rice or paddy rice, are still covered with coarse hulls that must be removed before the rice is cooked. Hulling may be done by machine in a rice mill, or the rice may be pounded by hand in a mortar. Rice with the hulls removed is called brown rice; it is covered with a brownish outer skin called the bran. Most people prefer to eat white rice, which has been milled to remove the bran. Some rice also is scoured in a machine called a pearler. Since nutrients are lost in the milling process, white polished rice is often enriched by adding vitamins and minerals._^<g_
Following primary and secondary treatment, about 85% of the pollutants in _^<a!T29514_sewage_^>a_ have been removed. Some sewage treatment facilities also perform tertiary treatment, which consists mostly of chemical processes such as distillation, electrodialysis, and reverse osmosis. These processes are used to remove nitrates, phosphorous, organic chemicals, heavy metals, and other dissolved substances. Following such treatment, about 95% of the pollutants in the original sewage have been removed._^<g_
The _^<a!T29525_sextant_^>a_ was invented independently by Thomas Godfrey, an American, and John Hadley, an Englishman, in 1730. The instrument derives its name from the fact that some instruments had a metal-frame arc of one-sixth of a circle, or 60 degrees. The instruments are now built with arcs of different degrees, but all of them are commonly called sextants. Sextants used in air navigation, though performing the same function as marine sextants, differ significantly because the natural horizon is seldom visible for use as a reference line from an airplane._^<g_See also: _^<a!T23274_navigation_^>a_._^<g_
As used by artists, _^<a!T29891_silk-screen printing_^>a_ typically is performed by hand with a silk screen and referred to as serigraphy. As used commercially, the process is typically performed mechanically using synthetic or metal screens and called screen printing or screen process. In either case, the ink is transferred to a receptive surface through a stencil supported on the mesh. The pores of the mesh are blocked by the stencil in the background, or nonimage, areas, and left open in the areas to be printed._^<g_
General use of the piston began about 1550, when it was used for pumping water from mines. In 1712, an English blacksmith and inventor named Thomas Newcomen built the first commercially successful piston-operated _^<a!T30923_steam engine_^>a_. Piston-operated _^<a!T16995_internal-combustion engines_^>a_ came later. A variety of successful models were built during the 1800s, and in 1876 _^<a!T24618_Nikolaus August Otto_^>a_, a German engineer, built the first successful four-stroke internal-combustion engine. Although many improvements have been made, present-day reciprocating internal-combustion engines are basically the same as that built by Otto._^<g_
In _^<a!T30614_speech_^>a_, the human voice has three basic characteristics: volume, pitch, and quality. Volume relates to the energy of the stream of air and the type of resonance provided. Pitch relates to the tension, length, and thickness of the vocal cords (vibration of the cords produces vocal tone). Quality depends on tone and on the resonance that reinforces this tone. Low nasal resonance makes a person sound like someone who has a cold. High nasal resonance makes it sound as though the person is talking through the nose._^<g_
_^<a!T13332_Gears_^>a_ are circular or cylindrical and have projections, called teeth, on either their external or internal surfaces. The teeth of sets of gears are designed to mesh. Because the teeth of spur gears are cut parallel to the working shaft, there is no side thrust on the shaft. Only a limited number of teeth can mesh at a given time._^<g_
The two-pole _^<a!T32012_telegraph_^>a_ key devised by _^<a!T22611_Samuel F. B. Morse_^>a_ in the 19th century is essentially a switch for opening and closing an electric circuit between two telegraph stations. When the transmission line is not in use, current flows from the power line through a bypass line. Depressing the key breaks the bypass contact, and a current pulse is sent through the transmission line contact._^<g_
_^<a!T3245_Alexander Graham Bell_^>a_ developed the first successful _^<a!T32020_telephone_^>a_ in 1876. A year later the first commercial telephone system went into operation, in Charleston, Mass. Automatic switching by number-dialing was conceived in 1881, but the first fully automatic dialing system wasn't installed until 1921, in Omaha, Nebr. The first microwave relay system went into service in 1947, between New York and Boston. Telstar, the first active communications relay satellite, was put into orbit in 1962. Digitalization, the key to multipurpose communications networks, came into use in the early 1960s. Digitalization involves converting a voice signal into computer language, transmitting it, and converting it back to its original form at the receiving end._^<g_
An _^<a!T32021_optical telescope_^>a_ must be properly located to collect as much light as possible. A dark sky relatively free of human lights is needed to observe faint celestial objects. The atmosphere should be clear and dry, to provide a steady image. Mountaintops offer the best locations on Earth, but today's astronomers also rely on space telescopes, which function as orbiting observatories. The _^<a!T30549_Hubble Space Telescope_^>a_ and the Keck Telescope in Hawaii are examples of reflectors. The large telescopes at _^<a!T19643_Lick Observatory_^>a_ in California and _^<a!T35628_Yerkes Observatory_^>a_ in Wisconsin are examples of refractors._^<g_
In _^<a!T32030_television transmission_^>a_, images and sound travel electronically. A television camera changes the light that is reflected from a scene into electronic signals. Then a device called a transmitter sends out the signals (along with signals for the accompanying sound, which has been picked up by microphone.) Finally, a _^<a!T32025_television_^>a_ receiver (or set) in the viewer's home receives the signals and converts them back into image and sound._^<g_
Lakes have _^<a!T32473_tides_^>a_ for the same reasons that oceans do. In small lakes, the tides are so small as to be unnoticeable. Even large lakes, such as Lake Superior, have tidal ranges of only a few inches. In the open ocean the tidal range averages between 0.6 and 0.9 m (2 and 3 ft). But in bays and gulfs and on the shores of continents and islands there are vast differences in tidal range. In places such as the Gulf of Mexico, the tidal range may be as little as 0.3 m (1 ft). At the other extreme, in the Bay of Fundy, between New Brunswick and Nova Scotia, the difference between high tide and low tide may reach 15 m (50 ft) or more._^<g_
_^<a!T33676_Valves_^>a_ range in size from small bicycle-tire valves to those 7.6 m (25 ft) in diameter for regulating water flow at hydroelectric plants. They are made of various materials and in a variety of shapes. Valves for general service typically are made of brass or bronze. Cast-iron valves are used to regulate fluids at moderate pressures and temperatures. Steel and alloy-steel valves are used to regulate fluids at very high pressures and temperatures._^<g_
The term _^<a!T34177__^<i_volcano_^>i__^>a_ is derived from Vulcano, one of the Lipari Islands north of Sicily, which in classical times was thought to be the entrance to the netherworld domain of Vulcan, the blacksmith god. Volcanoes have always terrified and fascinated people, as seen in many legends. They can devastate land with clouds of fire and steam, broadsides of boulders and rocks, and rivers of lava and hot mud. Active volcanoes are distributed in a series of belts, including one in the Atlantic Ocean, another along the eastern side of the Pacific Ocean, and a third that swings from the Bering Strait to the west side of the Pacific Ocean._^<g_
The apparent forward motion of _^<a!T34520_water_^>a_ as _^<a!T34550_waves_^>a_ sweep over the surface of the sea is an optical illusion. It is no more real than the apparent forward movement produced when a wheat field undulates in the breeze. In both cases the disturbance caused by the wind is transmitted from one area to the next. It is the wave pattern and not the water that moves forward. The highest point of a water wave is called the crest. The lowest point is called the trough. The distance from one crest to the next is known as the wavelength. The height of a wave of water is equal to the vertical distance between the crest and the trough. The time it takes a wave to pass from one crest to the next is called its period._^<g_
Atmospheric pressure can hold _^<a!T34520_water_^>a_ up to 10 m (33 ft) high in a vertical pipe when the bottom of the pipe is in water and the top of the pipe is closed. Often, however, there is some leakage out of the pipe, and the vacuum created is not perfect. For this reason, a well-water _^<a!T26849_pump_^>a_ is not expected to lift water more than about 7.5 m (25 ft) high at sea level._^<g_
The xerographic _^<a!T8100_copying_^>a_ process employs a coated selenium plate, which conducts electricity only when it is exposed to light. To make a copy, the plate surface is first positively charged in the dark by a moving high-voltage wire. In the exposure step, the original to be copied is illuminated by a light. The reflected light, which is thrown back only by the white areas, is projected onto the charged plate, causing the electricity to be dissipated wherever it strikes. In the developing step, a negatively charged toner powder is dusted over the plate, where it adheres to the remaining positively charged areas. A sheet of paper is placed over the plate and given a strong positive charge. The toner powder is attracted to the paper, where it forms a direct, positive image. The image is then stabilized by passing the print between heated rollers, causing the toner to melt and flow into the fibers of the paper._^<g_See also: _^<a!T10832_electrostatic printing_^>a_._^<g_
Director _^<a!T5570_James Cameron_^>a_ had taken the heat for a $200 million budget and a late release, so he was entitled to gloat a little when his blockbuster movie, _^<i__^<a!T32572_Titanic_^>a__^>i_, won a record-tying 11 _^<a!T139_Academy Awards_^>a_, including Best Picture and Best Director. By Oscar night in March 1998, the film had grossed more than $1 billion at the box office and was still going strong. (Reuters/Blake Sell/Archive Photos)_^<g_
At long last, peace in _^<a!T23873_Northern Ireland_^>a_ seemed within reach as a formal accord was signed in _^<a!T3227_Belfast_^>a_ on April 10, 1998. British Prime Minister _^<a!T3888_Tony Blair_^>a_ (right) and Irish Prime Minister _^<a!T505_Bertie Ahern_^>a_ (left) signed for their respective countries. According to the pact, brokered by former U.S. Senator _^<a!T22172_George Mitchell_^>a_ (center), Northern Ireland will remain part of the _^<a!T33448_United Kingdom_^>a_ unless a majority of voters in both the North and South opt for a unified _^<a!T17110_Ireland_^>a_. (Reuters/Dan Chung/Archive Photos)_^<g_
