Brotikasten/BROTCD01.iso/exoten/ancient.txt

Text File | 1995-08-20 | 19KB | 346 lines

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       A Chronology of Digital Computing Machines (to 1952)
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I thought this material would be of interest to this group, considering
the recent discussions of early computers.  I have compiled it from two
sources.  The primary one that I used is:

    Bit by Bit: An Illustrated History of Computers.
    By Stan Augarten, pub. 1984 by Ticknor and Fields, New York.
    ISBN 0-89919-268-8, 0-89919-302-1 paperback.

I recommend that book, by the way, but with some reservations.  The author
is a journalist rather than a computer person.  From time to time this shows,
but it's generally clear what he means even if he doesn't actually say that.
In any case, he does tell the story in an interesting and readable fashion.

For some material in the last part of the chronology I also consulted:

    Encyclopedia of Computer Science and Engineering, 2nd edition.
    Editor Anthony Ralston, Associate Editor Edwin D. Reilly Jr.,
    pub. 1983 by Van Nostrand Reinhold, New York.  ISBN 0-442-24496-7.

The criteria for including a machine in this chronology were that it either
was technologically innovative or was well known and influential; certain
particularly innovative inventions have also been included as of the first
time that they were described.  When I refer to a machine as being able to do
some operation, I mean that it can do it more or less without assistance from
the user.  This disqualifies the abacus from consideration, for instance;
similarly, a user wanting to subtract 16 on a 6-digit Pascaline could do it
by adding 99984, but this does not count as ability to do subtraction.

Where I do not describe the size of a machine, it is generally suitable for
desktop use if it has no memory and is unprogrammable, or is a small
prototype, but would fill a small room if it has memory or significant
programmability (of course, the two tend to go together).

The names Tuebingen, Wuerttemberg, and Mueller should have an umlauted
"u" in place of the "ue" used here.

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1623.    Wilhelm Schickard (1592-1635), of Tuebingen, Wuerttemberg (now in
    Germany), makes his "Calculating Clock".  This is a 6-digit
machine that can add and subtract, and perhaps includes an overflow
indicator bell.  Mounted on the machine is a set of Napier's Rods, a
memory aid facilitating multiplications.  The machine and plans are lost
and forgotten in the war that is going on.  (The plans were rediscovered
in 1935, lost again in the war, and re-rediscovered by the same man in 1956!
The machine was reconstructed in 1960 and found to be workable.)
    Schickard was a friend of the astronomer Kepler.

1644-5.  Blaise Pascal (1623-1662), of Paris, makes his "Pascaline".  This
    5-digit machine can only add, and that probably not as reliably as
Schickard's, but at least it doesn't get forgotten -- it establishes the
computing machine concept in the intellectual community.  (Pascal sold about
10-15 of the machines, some supporting as many as 8 digits, and a number of
pirated copies were also sold.  No patents...)
    This is the same Pascal who invented the bus.

1674.    Gottfriend Wilhelm von Leibniz (1646-1716), of Leipzig, makes his
    "Stepped Reckoner".  This uses a movable carriage so that it can
multiply, with operands of up to 5 and 12 digits and a product of up to 16.
But its carry mechanism requires user intervention and doesn't really work
in all cases anyway.  The calculator is powered by a crank.
    This is the same Leibniz or Leibnitz who co-invented calculus.

1775.    Charles, the third Earl Stanhope, of England, makes a successful
    multiplying calculator similar to Leibniz's.

1770-6.    Mathieus Hahn, somewhere in what is now Germany, also makes a
    successful multiplying calculator.

1786.    J. H. Mueller, of the Hessian army, conceives the idea of what came
    to be called a "difference engine".  That's a special-purpose calcu-
lator for tabulating values of a polynomial, given the differences between
certain values so that the polynomial is uniquely specified; it's useful
for any function that can be approximated by a polynomial over suitable int-
ervals.  Mueller's attempt to raise funds fails and the project is forgotten.

1820.    Charles Xavier Thomas de Colmar (1785-1870), of France, makes his
    "Arithmometer", the first mass-produced calculator.

1822.    Charles Babbage (1792-1871), of London, having reinvented the differ-
    ence engine, begins his (government-funded) project to build one by
constructing a 6-digit calculator using similar geared technology.

1832.    Babbage produces a prototype segment of his difference engine,
    which operates on 6-digit numbers and 2nd-order differences (i.e.
can tabulate quadratic polynomials).  The complete engine was to have
operated on 20-digit numbers and 6th-order difference, but no more than
this prototype piece was ever assembled.

1834.    Pehr George Scheutz, Stockholm, produces a small difference engine
    in wood, after reading a brief description of Babbage's project.

1836.    Babbage produces the first design for his "Analytical Engine".
    Whether this machine, if built, would have been a computer or not
depends on how you define "computer".  It lacked the "stored-program"
concept necessary for implementing a compiler; the program was in read-only
memory, specifically in the form of punch cards.  In this article such a
machine will be called a "program-controlled calculator".
    The final design had three punch card readers for programs and data.
The memory had 50 40-digit words of memory and 2 accumulators.  Its program-
mability included the conditional-jump concept.  It also included a form of
microcoding: the meaning of instructions depended on the positioning of
metal studs in a slotted barrel.  It would have done an addition in
3 seconds and a multiplication or division in 2-4 minutes.

1842.    Babbage's difference engine project is officially cancelled.
    (Babbage was spending too much time on the Analytical Engine.)

1843.    Scheutz and his son Edvard Scheutz produce a 3rd-order difference
    engine with printer, and the Swedish government agrees to fund
their next development.

1853.    To Babbage's delight, Scheutz and Scheutz complete the first really
    useful difference engine, operating on 15-digit numbers and 4th-order
differences, with a printer.

1858.    The difference engine of 1853 does its only useful calculation,
    producing a set of astronomical tables for an observatory in Albany,
New York.  The person who spent money on it is fired and the machine ends up
in the Smithsonian Institute.  (The Scheutzes did make a second similar machine,
which had a long useful life in the British government.)

1871.    Babbage produces a prototype section of the Analytical Engine's
    "mill" (CPU) and printer.  No more is ever assembled.

1878.    Ramon Verea, living in New York City, invents a calculator with an
    internal multiplication table; this is much faster than the shifting
carriage or other digital methods.  He isn't interested in putting it into
production; he just wants to show that a Spaniard can invent as well as
an American.

1879.    A committee investigates the feasibility of completing the Analytical
    Engine and concludes that it is impossible now that Babbage is dead.
The project becomes somewhat forgotten and is unknown to most of the people
mentioned in the last part of this chronology.

1885.    Dorr E. Felt (1862-1930), of Chicago, makes his "Comptometer".
    This is the first calculator where numbers are entered by pressing
keys as opposed to being dialed in or similar awkward methods.

1889.    Felt invents the first printing desk calculator.

1890.    US Census results are tabulated for the first time with significant
    mechanical aid: the punch card tabulators of Herman Hollerith
(1860-1929) of MIT, Cambridge, Mass.  This is the start of the punch card
industry (thus establishing the size of the card, the same as a US $1 bill
(then)).  The cost of the census tabulation