#Å#Å#Å“´#Å#Å.Ø*ÓKKXÃ3pk[xO\#Å
ý[o#Å00a£l]l\!V007x7w000000
000000000•Á•À00000000000010000ÊÉÉ‘0000e?d<l_‹uÔ_‹näÕ0
00ãd_‹ããããddã_‹m‘{‘z‘z†.ã0000000000ššˆXˆWš0000
00000000000˜000000zÒ]'j00000000D 00000000000000V€00q‘0
00000000„;«Éªª„:000000000000000000hFhE00Fp|û000000000000
00000Oí5¿OìOìOì000000000000Tg-00M›00000000000000000000e0000000
sÅ00000000000000(Ae±e°AYe°0000ŠÄŠÃŠÃ000000&00\0000000000000000
00000000000000000[[[XÄXÃXÃXÃ9å]
þ=R\ó\<.Ù.Øc½c¼
ý[R0
#Å#Å#Å0
*NAVIGATION
The sailors of antiquity studied the night sky. Reading the sky map, they
could sail away from sight of the shore, knowing that steering by certain
reliable stars would bring them home. This crude, practical application of
ASTRONOMY allowed the adventurous to sail into the unknown with a reasonable
chance of finding their way. Wind-powered ships risked longer voyages, tempted
by the knowledge, trade, and new settlements offered by distant lands. The
maps of the known world expanded as the blanks were filled in by the reports
of the sailors who had mastered NAVIGATION. 

*CONSTRUCTION
Advancing beyond the use of mud bricks and mortar to build homes and walls,
ancient engineers responded to the need for stronger, more elaborate
structures by developing new techniques and skills in CONSTRUCTION. The
preferred building material became stone. These new skills made possible the
aqueducts, city walls, palaces, temples, bridges, and roads that still stand
today in many places, testaments to the ancient builders. In CIVILIZATION,
Construction allows Settler units to construct Fortresses.

*HORSEBACK RIDING
Horses are believed to have been first domesticated in the great plains of
northern Asia. Mounted horsemen from this region migrated into the more
civilized parts of Europe and Asia, often driving out or enslaving the
inhabitants. Where the horse could be raised, HORSEBACK RIDING was extremely
useful as a source of power and means of transportation. It proved especially
valuable in battle, making the rider much more imposing and mobile. Mounted
warriors were part of most armies until their role as scouts and Cavalry was
superseded by vehicles and aircraft.

*CEREMONIAL BURIAL
Groping for an explanation of the world around them, the earliest humans
developed the first concepts of religion. These early forms of worship
attempted to give order to the world and assign humans a role in the universe.
Gradually the rites of worship grew more sophisticated with sacrifices,
ceremonies, vigils, symbology, sacred items, and prayer. One significant step
in the advance of worship was the CEREMONIAL BURIAL, often a preparation for
an afterlife. The remains of CEREMONIAL BURIALS offer some of the most
detailed information available of past civilizations.

*POTTERY
Concomitant and essential to the Agricultural Revolution was the invention
of POTTERY. For seasonal crops and domesticated animals to be really useful,
sturdy and waterproof containers were necessary to hold and protect the
surplus until needed. The discovery of the properties of clay, the kiln, and
the potter's wheel made dependable containers possible. POTTERY was essential
to the growth of substantial human populations. Without it, cities would not
have been possible.

*ALPHABET
An ALPHABET is a group of symbols that represents phonemes, sounds that humans
can make or distinguish. Some ALPHABETS represent syllables. The ancestors of
modern ALPHABETS are the iconographic and ideographic symbols of ancient man
such as cuneiform and hieroglyphics. The modern ALPHABET of the West traces
back to the Romans, then to the Greeks, and then to the Phoenicians. The
ALPHABET was significant because ideas could now be transferred by being
painted on pottery, carved in stone, or impressed in clay. Ideas no longer
had to be exchanged face-to-face by voice or hand signals.

*ADVANCED FLIGHT
The technology of FLIGHT advanced rapidly in the 20th Century, especially
during the two World Wars when the contending nations raced against each other
for air superiority. ADVANCED FLIGHT technology was a specialty of the Germans
in World War II. They developed the first practical jet fighters, extremely
long-ranged Bombers, and the first guided rockets. However, these innovations
could not be produced in sufficient quantities to be really useful. The Allies
mass-produced less innovative, but dependable, aircraft that won the air war.

*ASTRONOMY
Perhaps the oldest of the sciences, ASTRONOMY originated by observing the
regularity of celestial movements. The earliest astronomers were priests who
were often able to use the predictability of events to maintain their
power. Ancient Greek students of ASTRONOMY understood that the Sun was the
center of the Solar System, made reasonable estimates for the size and
distance of the Sun and Moon, and made a close estimate of the size of the
Earth. These facts not rediscovered in the West for over one thousand years.
Much later, ASTRONOMY became important in timekeeping and NAVIGATION.  

*ATOMIC THEORY
Greek philosophers first proposed that matter was composed of tiny,
indivisible particles in constant motion. However, this concept was not
popular at the time, especially with Aristotle, and disappeared.
Independently, ATOMIC THEORY was revived in the 19th Century. Advances in
PHYSICS, especially the development of quantum mechanics, provided a
satisfactory explanation for the behavior of electrons and other sub-atomic
particles. An understanding of ATOMIC THEORY made possible the development of
NUCLEAR FISSION and atomic weapons.

*AUTOMOBILE
The first practical AUTOMOBILES were developed in the late 19th Century,
although experiments with steam-powered wagons had been carried out over one
hundred years earlier. The critical invention that made the AUTOMOBILE a
success was the internal COMBUSTION engine. This relatively small but powerful
engine could be mounted within the frame of the "horseless carriage" and drive
the wheels. The AUTOMOBILE had a tremendous impact on the economy and
lifestyles of the rich Western nations, and it also revolutionized warfare.
Armed and armored AUTOMOBILES, known as tanks, became a dominant weapon on the
battlefield.

*BANKING
Modern BANKING arose during the Renaissance among the merchant families of the
Italian city-states who were benefiting from the increase in TRADE, both
within Europe and with the Middle East. The wealthy merchants pooled their
surplus money into a Bank, and loaned cash at interest to other commercial
enterprises. The availability of this capital for investment made many new
businesses possible and helped accelerate economic growth. BANKING was even
more important after the Industrial Revolution due to the even larger capital
investments required by the newly rising industrial CORPORATIONS.

*BRIDGE BUILDING
An important measure of the advancement of any civilization was the internal
CONSTRUCTION improvements built to facilitate trade and communication. The
Roman Empire was renowned for its roads, aqueducts, and other structures that
linked the frontiers to the capital. BRIDGE BUILDING was greatly advanced by
the Romans, and rediscovered in the West by medieval engineers many years
later. The first IRON bridge was built in England in the late 18th Century,
and BRIDGE BUILDING techniques advanced rapidly to meet the demands of the
expanding RAILROADS of the 19th Century.

*BRONZE WORKING
BRONZE is an alloy of copper and other metals, mainly tin. BRONZE WORKING
technology grew out of experiments with copper ore, which was often found pure
enough in ancient times to be worked into metal objects. Experiments with the
distinctive greenish copper ore led to mixtures of metals into BRONZE. The new
metal proved much more useful than copper because it was harder, less brittle,
and could hold a sharper edge. It made better, less costly tools, and was very
useful for making weapons and armor. The first societies possessing BRONZE
weapons had a distinct advantage over those armed with stone or copper.

*CHEMISTRY
The basis for modern CHEMISTRY was laid by the pseudo-science of alchemy, which
attempted to turn base metals into gold and silver through the agency of an
elixir or Philosopher's Stone. Alchemy periodically surfaced and degenerated
until the real science of CHEMISTRY was found to have economically useful
applications. CHEMISTRY was also spurred by the practical needs of MEDICINE
and the theoretical considerations of natural PHILOSOPHY.

*CHIVALRY
CHIVALRY was a system of ethical ideals that grew out of FEUDALISM. It
established a code of behavior for the landed class of mounted warriors, known
as Knights. The chief chivalric virtues were piety, honor, valor, courtesy,
chastity, and loyalty. These represented a fusion of Christian and military
morality and became the basis for gentlemanly conduct. The zenith of CHIVALRY
were the Crusades, a series of invasions of the Middle East that attempted to
recapture the Holy Land from the Muslims. CHIVALRY was enhanced by monastic orders of
knighthood, including the Knights Templar and Knights Hospitaler. 
 
*CODE OF LAWS
As populations and cities grew, the need grew for the establishment of rules
of conduct within the newly organized societies. After the development of the
ALPHABET, these rules were written down along with the punishments that kept
them enforced. The earliest known such codes existed in Babylon, India, and
Palestine. Roman law was the first to distinguish between public law, in
which the state is involved, and private law, concerning disputes between
citizens. U.S. law was greatly influenced by the work of Sir William
Blackstone, who stressed the natural rights of the individual.

*COMBUSTION
The development of the internal COMBUSTION engine was a great advance of the
Industrial Age. Relying on the volatility of new fuels made available by the
REFINING of oil, these compact engines developed great power. They were
essential to the development of the AUTOMOBILE and aircraft because previous
engines were too bulky to be practical. In addition, the internal COMBUSTION
engine was extremely efficient in generating power for the fuel it consumed,
which allowed vehicles, aircraft, and ships to travel reasonable distances.

*COMMUNISM
COMMUNISM developed as a system of social organization where the real property
(land) and means of production (factories) were owned by all. Experiments with
this system appeared at various times in the past, but COMMUNISM in the world
today arose from the often appalling living conditions that came into being for
the factory workers during the Industrial Age. Outrage over the greed of the
new capitalists and the poverty of the workers led to the Communist Manifesto
of Marx and Engels that predicted the rise of a classless society. COMMUNISM
has failed so far to fulfill its promise of an egalitarian society based on
working-class values.

*COMPUTERS
A COMPUTER is a device capable of performing a series of arithmetic or logical
operations. It is distinguished from a calculator by being programmable and
capable of storing and retrieving data. COMPUTERS are made possible by
previous advances in MATHEMATICS and continuing developments in ELECTRONICS.
Significant advances in COMPUTER technology take place at an amazing pace.
COMPUTERS have proven useful and necessary in many applications, including
huge computations, entertainment, information storage, cryptography, and
and control of ROBOTS.

*CONSCRIPTION
Compulsory enrollment in the armed forces, or CONSCRIPTION, was introduced in
France during the Revolution. It was thought necessary and equitable by the
new government surrounded by enemies. In the era of national mobilization for
war that followed, wartime CONSCRIPTION was instituted by many nations,
including most major participants in the World Wars. In the U.S., peacetime
CONSCRIPTION was maintained for nearly 30 years following World War II.  

*CURRENCY
As cities grew, their internal economies became more complicated. People
specialized in their labors, some producing grain, some pottery, some bricks,
etc. A system of barter developed so that the wares and services of one
individual could be exchanged for those of another. In response to the need
for a medium of exchange, and for more sophisticated ways to store purchasing
power and set standards of value, CURRENCY came into use. The first
satisfactory CURRENCY was coinage made from electrum, a naturally occurring
alloy of gold and silver.

*DEMOCRACY
A system of government where all of the people share in directing the
activities of the state was called a DEMOCRACY. This type of government first
arose in some of the ancient Greek city-states, though slaves and women did
not participate. The modern DEMOCRACIES of the West developed over time,
tracing back to the Magna Carta agreement signed by King John of England in
the 13th Century. Government run by elected representatives of the people was
the basic concept of modern DEMOCRACY. DEMOCRACY made possible unprecedented
personal and economic freedom, and the world's strongest economies to date.
 
*ELECTRICITY
The phenomenon of ELECTRICITY has been witnessed by humans since the dawn of
time in the form of lightning, static ELECTRICITY, and MAGNETISM, but only in
the last two hundred years has the energy of charged particles been harnessed.
Electric current is a flow of electrons from an electromotive force, such as
a battery or generator, that possesses a negative charge. The current flows
through a conductor of electricity (a copper wire for example) to a positive
terminal that attracts the charge. Along the way, the electric current can be
made to provide power and do work.

*ELECTRONICS
ELECTRONICS is the science of understanding and ENGINEERING the controlled
flow of electrons in electronic currents. Historical breakthroughs that have
occurred in ELECTRONICS include the electronic tube, semiconductor,
transistor, and integrated circuits. These made possible COMPUTERS, advanced
weapons, improved radars, and communication receivers, as well as more
efficient techniques in power generation and transmission.

*ENGINEERING
The science of ENGINEERING originated with the civil engineers, who built
bridges, roads, aqueducts, and other structures, and the military engineers,
who built fortifications and weapons. Over time, ENGINEERING came to mean the
design, CONSTRUCTION, and operation of the structures and machines of
industry, warfare, and day-to-day life. Engineers were the people who put the
new advances of knowledge to practical use. They were people not only good
with their hands, but also with their heads. The ENGINEERING problem-solver
was most likely to discover a new INVENTION and lead the advance of knowledge.

*EXPLOSIVES
EXPLOSIVES were discovered during experiments with GUNPOWDER and CHEMISTRY in
the search for stable and powerful chemicals for industrial and military
applications. An EXPLOSIVE is a chemical that undergoes a rapid COMBUSTION,
and produces much heat and gas. The heat causes the gas to rapidly expand,
thereby exerting the pressures of an explosion. Some EXPLOSIVES are mixtures
of combustibles that are ignited. Others contain unstable molecules that can
undergo an EXPLOSIVE decomposition called a detonation. The former type is
used as propellants for bullets and fireworks, while the latter is used in
warheads and rock blasting.

*FEUDALISM
In the unsettled times that followed the collapse of Charlemagne's Frankish
empire, a new social and political system arose in Europe, called FEUDALISM.
Derived from the concept of MONARCHY, it was a hierarchial system where each
succeeding stratum owed allegiance to those above. At the bottom were the
serfs, who worked the land for the lord of the local manor. The local lord in
turn managed the land for the lord above him, and so on to the king, who
actually owned all the land. The people at the bottom of the hierarchy were
protected by those above, and in return served their masters. FEUDALISM led to
the code of CHIVALRY and the mounted Knight.

*FLIGHT
Sustained, self-powered motion through the air, or FLIGHT, has tantalized
humans since the dawn of time. Despite many experiments and attempts at flying,
it wasn't until the development of the internal COMBUSTION engine that the laws
of PHYSICS could be made to work for man's quest. Just after the turn of the
20th Century, Orville and Wilbur Wright made the first four controlled,
sustained flights at Kitty Hawk, N.C. The technology of FLIGHT advanced
rapidly. Within a relatively few years, aircraft were circling the globe,
safely delivering passengers and mail at record speeds.

*FUSION POWER
Nuclear FUSION is the process by which two atomic nuclei combine to form one
heavier atomic nucleus, giving off tremendous energy in the process. The
difficulty with sustaining this thermonuclear reaction is that it requires very
high temperatures for initiation and fuel containment. An answer to part of the
problems of FUSION may lie in the development of SUPERCONDUCTORS. Nuclear
FUSION offers great promise as a source of electric power because a safe fuel
is available in large quantities and the process does not create the
radioactive waste that plagues Nuclear FISSION. In CIVILIZATION, FUSION POWER
eliminates the risk of a Nuclear Power Plant meltdown.

*GENETIC ENGINEERING
One of the hopes in the search for a cure for cancer and many other diseases
and disorders comes from GENETIC ENGINEERING, a new field of study in science
and MEDICINE. GENETIC ENGINEERING is a group of techniques that manipulate the
genetic material of living cells. Gene splicing is a technique for
transporting genetic material from one species to another. Other techniques
include cell fusion and nuclear transplantation. The hope is that DNA, the
basic genetic material for all life, may prove to be repairable and
changeable. Then all genetic disorders would no longer be permanent, but
curable.

*GUNPOWDER
GUNPOWDER is a chemical mixture of saltpeter, sulphur, and charcoal. When
ignited, it burns so rapidly that it explodes if contained to any degree.
GUNPOWDER is believed to have been developed by the Chinese as early as the
9th Century, but did not reach Europe until the 1300's. The Chinese appear to
have used it almost exclusively for fireworks, but the competing and
aggressive Europeans turned it into weapons that revolutionized warfare.
Musketeers and Cannon brought an end to the battlefield dominance of heavy
Cavalry and also ended recurring invasions of barbarians from Asia.

*HORSEBACK RIDING
The HORSE was first domesticated by tribesmen on the Asian steppes. It was
used by these tribes for transportation and warfare, and with its help they
overwhelmed the proto-civilizations just rising in southeast Europe and the
Middle East. HORSEBACK RIDING was in turn acquired by the conquered peoples
and this skill accompanied the spread of civilization. In areas where the
HORSE could be bred, it was extremely useful for transport and agriculture.
Only in the last one hundred years has the HORSE been replaced by motor
vehicles as a draft animal and mount for Cavalry.

*INDUSTRIALIZATION
The invention of the STEAM ENGINE and other technology, especially the
RAILROAD, led to the INDUSTRIALIZATION of the West. INDUSTRIALIZATION was the
use of machines to dramatically increase the productivity of workers. Industry
became concentrated in factories, allowing new products to become available in
huge quantities. INDUSTRIALIZATION revolutionized living standards, but not
always for the better. The new worker class often suffered a grinding,
subservient existence that eventually fostered the social philosophy of
COMMUNISM and the more practical LABOR UNION. Both were attempts to improve
the lot of workers.

*INVENTION
The contrivance of a previously unknown device, method, or process is known as
an INVENTION. The advance of technical knowledge is essentially the discovery
of new INVENTIONS. The history of civilization shows that the spread of
LITERACY and the rise of ENGINEERING specialists were critical to the
acceleration of new technology. ENGINEERING is the practical employment of
INVENTION, and people who do this work are often the ones who identify the
need for further advance and achieve it. The progress of a society is a
measure of how well it encourages and adapts new INVENTIONS.

*IRON WORKING
Building on the experience of their BRONZE WORKING, ancient smelters learned
IRON WORKING, the manufacture and fabrication of a much more useful metal. Iron
ore was extremely common compared to copper and tin, and IRON was harder, less
brittle, and could hold a much sharper edge. It was an ideal material for tools
and weapons. Some observers consider the development of IRON WORKING to have
been a key step in the advance of civilization. It made workers much more
efficient and was found useful in many new applications.

*LABOR UNION
With the rise of MASS PRODUCTION in the Industrial Age, the balance of power
between owners and workers swung too far in favor of the owners. The rising
worker class often found themselves stuck in poor working and living conditions
while the owners grew rich. In response to this inequity the LABOR UNION arose,
an attempt by the workers to bind their interests together and collectively
bargain with ownership for better working conditions and economic status. After
much turmoil, the LABOR UNIONS were able to achieve a working balance of power
with ownership and improve the worker's lot.

*LITERACY
The development of WRITING made available a critical new tool for the advance
of knowledge, but, like all tools, it was only useful if employed.  The greater
the percentage of the population that was LITERATE, the greater the advantage
that could be taken from WRITING. Where only priests and scribes were LITERATE,
all others had to share knowledge slowly, by face-to-face contact. When a high
percentage of the population was LITERATE, as in classical Greece, the economy
benefited and the advance of knowledge accelerated.

*MAGNETISM
The force of attraction or repulsion between various substances, especially
iron, is due to the motion of electric charges and is known as MAGNETISM. A
MAGNETIC object normally has two poles, a north-seeking pole and a south-
seeking pole, named because a freely floating MAGNET orients itself in the
Earth's MAGNETIC field along a north-south axis. MAGNETISM may have been
discovered in China, but its important application in the mariner's compass
occurred in 12th Century Europe. Later work with MAGNETISM was important in
the discovery of PHYSICS and ELECTRICITY.

*MAPMAKING
MAPMAKING was an offshoot of the development of the ALPHABET. With this
technology if became possible to record the location of important places and
features on animal skins, clay tablets, tree bark, or other materials, and thus
pass on this information to others. This was especially useful to seamen, who
often ventured far from home along strange coasts with their only guide being
the MAPS made by those who had sailed there previously. MAPMAKING encouraged
travel and exploration by making it less risky. It was the beginning of the
skills that became the science of NAVIGATION.

*MASONRY
The aggregation of people into the first cities required permanent buildings.
To fill the need for these structures, some of the new city dwellers became
expert in the techniques of MASONRY. This technology utilized rocks and mud
bricks, cementing these materials into buildings and walls. With experience,
their buildings grew larger and more elaborate, walls became more imposing, and
the work became more permanent and pleasing to the eye. Years of experience led
to more sophisticated techniques of CONSTRUCTION.

*MASS PRODUCTION
Following the advent of INDUSTRIALIZATION, factory owners developed new
techniques to make production more efficient. Henry Ford is credited with one
major advance, the installation of MASS PRODUCTION assembly lines in his
AUTOMOBILE plants. In this case, the object being assembled, a car, was carried
along conveyor belts to the various workstations, where each worker expertly
performed his part of the assembly. When the car reached the end of the line,
it was fully built. Techniques such as this resulted in dramatic increases in
worker productivity as long as the workers were content.
 
*MATHEMATICS
From the earliest ALPHABETS, some symbols came to represent the concept of
numbers. MATHEMATICS arose from the needs of agriculture and commerce to keep
track of quantities, accounts, and measurements. Farmers needed to know the
size of the yield from their fields. Traders needed to know what they had
available for barter and the rates of exchange. MASONS needed to know the
dimensions of the structure they were building. The development of MATHEMATICS
was critical to the future advance of PHYSICS and other sciences.

*MEDICINE
The study of the body and healing was first developed into a science by the
Greeks. Hippocrates, considered the father of MEDICINE, based his studies of
the human body on observation and reasoning. His studies were just one of many
breakthroughs that resulted from the flowering of Greek PHILOSOPHY. Though some
of his beliefs were incorrect, many modern medical students take the
Hippocratic Oath upon graduation, swearing to uphold his principles. MEDICINE
and alchemy were the basis for the developing science of CHEMISTRY.

*METALLURGY
The science of METALLURGY became especially important after the development of
GUNPOWDER, as the European powers vied with one another for the latest
technological advance in weapons. Research in METALLURGY was conducted by the
private smelters and UNIVERSITIES. The result was artillery and naval guns
superior to any in the world. This development was an important factor in the
rise of European states as world powers. METALLURGY later led to the discovery
of STEEL and other metals.

*MONARCHY
The MONARCHY developed from the absolute rule of the prehistoric tribal chief.
This type of absolutism evolved first into a hereditary and lifelong right to
rule, and was later claimed as a divine right. The MONARCHY was made possible
by the enforcement of LAWS put in place by the rulers and their supporters who
had the most to gain from maintaining control. It was more practical than the
despotism it often replaced because the ruler's power was not absolute and
arbitrary, but generally dispensed through an aristocratic class of local
rulers. The aristocrats served as a check on the ruler's power, blocking
projects not in their own interest.

*MYSTICISM
As populations and knowledge grew, a new class of spiritual advisors arose to
satisfy the need for less formal, state-centered rites of worship. The
priests and priestesses of MYSTICISM, often called oracles, claimed union with
the divine through meditation and trance-like contemplation. MYSTICISM offered
for the first time the hope of personal salvation and immortality, concepts
important in the development of later RELIGIONS.

*NUCLEAR FISSION
NUCLEAR FISSION occurs when a fissionable atomic nucleus absorbs a neutron,
becomes unstable, and splits into two new nuclei. In the process, tremendous
energy is given off as heat, light, and radioactivity. The first use of NUCLEAR
FISSION was in warfare, where the heat and shock wave of uncontrolled fission
produced an unprecedented weapon, the atomic bomb. Later, controlled NUCLEAR
FISSION was employed to provide enough heat to power the generation of
electricity in a NUCLEAR POWER Plant. The dangers and risks associated with
NUCLEAR POWER have so far limited its employment.

*NUCLEAR POWER
The development of NUCLEAR POWER was an attempt to find a peaceful application
for the energy released by NUCLEAR FISSION. The heat given off created steam
that drove electric turbines, producing electricity. NUCLEAR POWER held the
promise of being cleaner and less costly than burning fossil fuels.  However,
the radioactive materials consumed in the process were extremely lethal, the
disposal of nuclear waste was difficult, and the risk of nuclear meltdown could
not be eliminated. Continuing work may lead to a safer application. For
example, employing reactors built on the principles of nuclear FUSION, rather
than FISSION, may yet provide safe, clean power.

*PHILOSOPHY
In ancient Greece, LITERACY and interest in the natural world was common in an
expanding upper class that devoted much of its leisure time to debate. Popular
topics for discussion were the reality, causes, and principles of thinking and
being, better known as PHILOSOPHY. These debates considered the facts
independent of the traditional religious dogmas of the day, and opened the door
to examination of a wide range of new ideas. The writings of many of these
early Greek philosophers, including Plato and Aristotle, have been luckily
preserved. It has been said that all PHILOSOPHY after Plato was no more than
footnotes to his work.

*PHYSICS
The study of PHYSICS came into being from abstract theories of MATHEMATICS and
the practical experience of engineers and sailors. Concerned with the study of
matter and energy, and the relationships between them, classical PHYSICS dealt
with phenomena within the bounds of normal observation: motion, acoustics,
thermodynamics, and optics. These studies in turn led to further advances in
areas such as MAGNETISM and ELECTRICITY. Modern PHYSICS is primarily concerned
with the behavior of matter and energy under extreme conditions or at extreme
scales.

*PLASTICS
One of the spinoffs of research in the REFINING of oil was the discovery of
PLASTICS, organic compounds that can be molded under heat and pressure.
PLASTICS appeared to be wonders of the Industrial Age and were found to be
cheap and sturdy substitutes for more traditional materials in all manner of
uses. But the widespread use of PLASTICS led to environmental problems because
the material does not decay. Disposal by incineration was complicated because
it melts, clogs equipment, and may give off harmful fumes.

*RAILROAD
The RAILROAD resulted from the successful marriage of a promising new
technology, the STEAM ENGINE, and a growing need: fast, safe, and inexpensive
transportation. RAILROADS applied the unprecedented power of the locomotive to
the pulling of trains of loaded wagons over rails. This resulted in a dramatic
increase in the amount of cargo that a few men could move quickly and over
great distances. RAILROADS were a critical contributor to INDUSTRIALIZATION.
They not only made it easier to obtain raw materials and reach markets, but the
search for better equipment spurred innovation that benefited many other
industries.
 
*RECYCLING
Although scrap metals and other materials have been reused in manufacturing
processes for some time, only recently has RECYCLING become a household
concern. Increasing world populations and the flow of products off the MASS
PRODUCTION lines are threatening to choke our planet in refuse and pollution.
In the DEMOCRACIES of the West, the richest nations and the most wasteful, a
movement is underway to reuse as much refuse as possible. When RECYCLED, old
newspapers used again spare trees, plastic bottles save oil, and aluminum cans
save electricity. RECYCLING reduces costs and pollution, thereby improving the
quality of life.

*REFINING
Mineral tar and petroleum have been known throughout history, but little use
was found for either until it was discovered through CHEMISTRY that oil could
be REFINED into chemicals with a wide variety of uses. The primary application
of oil derivatives was as fuel for internal COMBUSTION engines that powered the
AUTOMOBILE and other machines. Oil had to await the Industrial Revolution
before its potential could be realized, because large CORPORATIONS could afford
the investments in AUTOMOBILE production and REFINING that were required.

*RELIGION
The evolution of RELIGION traces back to elementary forms of belief and
practice concerning the extraordinary, the mysterious, and the supernatural.
RELIGION gave people an object of devotion, a code of social behavior, and a
reference for the individual within the group and the universe. Acceptance of
the teachings of RELIGION brought peace of mind and the ability to get on with
the work of life, because the terrifying questions of the unknown were
contained. The advance of knowledge that followed the development of WRITING
and the study of PHILOSOPHY led to the great RELIGIONS of the modern world.

*ROBOTICS
Advances in COMPUTER technology have made possible the new science of ROBOTICS,
which was previously the realm of science fiction. ROBOTICS concerns the design
and building of machines capable of mimicking some modicum of human action.
These machines can sense changes in their environment and take limited action
based on this information. ROBOTS are essentially computer-controlled machine
tools that can be programmed to perform tasks such as welding car parts. They
are especially useful for tasks that are monotonous, dangerous, or tiring,
where they are often more productive than their human counterparts.

*ROCKETRY
Although experiments with ROCKETRY trace back to Chinese fireworks powered by
GUNPOWDER one thousand years ago, most of our current knowledge was developed
in the 20th Century. A ROCKET is propelled by the ejection of gases created by
the COMBUSTION of on-board fuel. The COMBUSTION creates great pressure that is
vented through the rear, and this thrust against the front interior of the
COMBUSTION chamber pushes the ROCKET forward. The first practical guided
ROCKETS were used in World War II. More recently, ROCKETS have been used to
propel intercontinental ballistic weapons and launch spacecraft.

*SPACE FLIGHT
Following the development of the first guided missiles in World War II, the
science of ROCKETRY advanced to the point where direct space exploration
became possible. SPACE FLIGHT advanced from simple sub-orbital flights to
manned missions to the Moon. Work continues today on building space stations
and reusable space vehicles. In the near future there may be a manned mission
to Mars. In succeeding generations, new advances may make manned travel to
other star systems practical.
 
*STEAM ENGINE
Some of the properties of steam have been known since ancient times, but it
took thousands of years of groundwork in PHYSICS and the practical skills of a
few INVENTORS to build a working STEAM ENGINE. The beauty and value of this
engine was that it could do the work of many men. A STEAM ENGINE operator
could have his strength multiplied enormously by tapping the heat energy
released by burning coal. The STEAM ENGINE was the prerequiste for the
Industrial Revolution, leading to the spread of Factories and RAILROADS around
the world.

*STEEL
With the Industrial Revolution came new needs for metals, both as construction
materials and for fabrication into products. The rise of RAILROADS especially
spurred research in METALLURGY for a metal that could be fashioned into cheap,
strong rails and bridges. Eventually, the secret of STEEL was discovered, and 
it was found to be a nearly perfect construction material. However, it could
not be made cheaply until INDUSTRIALIZATION brought the resources and machines
together at one time. In turn, STEEL led to great changes in the world,
including enormous skyscrapers, armored warships, and the AUTOMOBLE.

*SUPERCONDUCTOR
When electric current is passed through a conductor, such as a copper wire,
a small but significant amount of the current is lost to resistance. When
certain substances are cooled to temperatures near absolute zero, this
resistance disappears. This phenomenon is called superconductivity, and a
substance with no electrical resistance is a SUPERCONDUCTOR. If such a
material could be found that worked at something nearer normal temperatures,
its discovery might revolutionize everyday life by greatly reducing the cost
of energy and making hosts of new inventions practical.

*THE CORPORATION
The RAILROADS, iron mongers, and other businesses that launched the
Industrial Revolution grew into great enterprises within a generation, far
outstripping the resources of a single owner. The huge capital investments
that INDUSTRIALIZATION required were met in the West by CORPORATIONS of
stockholders that had access to sophisticated BANKING systems. These large
industrial enterprises now dominate world business. Though often considered
wasteful, conspiratory, and beyond the law, they are generally efficient and
innovative, or they are soon out of business.
 
*THE REPUBLIC
The concept of THE REPUBLIC first appeared in ancient Rome, where the local
provinces sent representatives to the Senate to govern the nation. The head of
state in a REPUBLIC was an elected representative, not a MONARCH. The concept
was revived in the Constitution of the United States, and many nations of
significant size and diverse make-ups have adopted something similar. THE
REPUBLIC allowed unprecedented freedom, at least to a significant portion of
the citizens, and this in turn often fostered strong economic growth.

*THE WHEEL
One of the five great simple machines, the WHEEL and axle greatly increased
the load that a human or animal could pull by lowering the resistance to
movement. The WHEEL was also quickly turned into a weapon of war after its
invention, especially in the adaptation of the Chariot. In addition to its use
in transport, the WHEEL became a vitally important tool in ENGINEERING and in
the Industrial Age. In the pre-Columbian New World, the WHEEL only appeared in
children's toys, partly because the mountainous terrain of South America made
it less practical.

*THEORY OF GRAVITY
The attracting force that exists between any two particles of matter is called
gravity. This force exists throughout the universe and explains the behavior
of both the apple that fell on Newton's head and the orbit of the Earth around
the Sun. The THEORY OF GRAVITY is credited to Sir Isaac Newton, who first
recognized that gravitation was universal. His work opened the door to later
scientists including Albert Einstein, who developed the Theory of Relativity,
and the men who developed ATOMIC THEORY.

*TRADE
One of the oldest and most widespread social institutions is the exchange of
goods, or TRADE. At the most basic level of TRADE, two people exchange items
with each other. Ideally, the items given are in surplus and the items received
are desired. The result is that both are better off, having exchanged extras
for something wanted. People, as well as nations, normally have a comparative
advantage over others in the production of some good or service. Through TRADE,
this advantage benefits both parties. TRADE has also proven very important in
the exchange of ideas.

*UNIVERSITY
The first UNIVERSITIES were founded in the Middle Ages by ecclesiastical or
royal initiative to train young men in law, theology, and medicine. The modern
UNIVERSITY consists of several faculties, or colleges, each with a specific
curriculum. Traditionally, only UNIVERSITIES granted graduate degrees, but that
distinction is now blurred. During the 20th Century many UNIVERSITIES,
especially in the U.S., received large government grants for scientific and
technological research, especially research related to weapons.

*WRITING
The development of WRITING is considered one of the most important advances of
civilization. From that point, history began, as defined by written records
first inscribed on clay tablets or carved into stone. The significance of
WRITING is that it allowed ideas and knowledge to be stored and passed on over
distance and time, far removed from the originator. Prior to this,
communication had to take place face-to-face. WRITING greatly accelerated the
advance of knowledge because what was known in the past did not have to be
relearned by each new generation.

*END