【正文】 ● 電腦大事記 |電腦發(fā)展大事記（英文版） A Brief History of Computing Complete Timeline 169。 Copyright 199620xx, Stephen White 500 . The abacus was first used by the Babylonians as an aid to simple arithmetic at sometime around this date. The abacus in the form we are most familiar with was first used in China in around 1300 . 1614 Scotsman John Napier (15501617) published a paper outlining his discovery of the logarithm. Napier also invented an ingenious system of moveable rods (referred to as Napier’s Rods or Napier’s bones). These allowed the operator to multiply, divide and calculate square and calculate cube roots by moving the rods around and placing them in specially constructed boards. 1623 Wilhelm Schickard (15921635), of Tuebingen, Wuerttemberg (now in Germany), made a Calculating Clock. This mechanical machine was capable of adding and subtracting up to 6 digit numbers, and warned of an overflow by ringing a bell. Operations were carried out by wheels, and a plete revolution of the units wheel incremented the tens wheel in much the same way counters on old cassette deck worked. The machine and plans were lost and fotten in the war that was going on, then rediscovered in 1935, only to be lost in war again, and then finally rediscovered in 1956 by the same man (Franz Hammer)! The machine was reconstructed in 1960, and found to be workable. Schickard was a friend of the astronomer Johannes Kepler since they met in the winter of 1617. 1625 William Oughtred (15751660) invented the slide rule. 1642 French mathematician, Blaise Pascal built a mechanical adding machine (the Pascaline). Despite being more limited than Schickard’s ’Calculating Clock’ (see 1623), Pascal’s machine became far more well known. He was able to sell around a dozen of his machines in various forms, coping with up to 8 digits. 1668 Sir Samuel Morland (16251695), of England, produces a non decimal adding machine, suitable for use with English money. Instead of a carry mechanism, it registers carries on auxiliary dials, from which the user must reenter them as addends. 1671 German mathematician, Gottfried Leibniz designed a machine to carry out multiplication, the ’Stepped Reckoner’. It can multiple number of up to 5 and 12 digits to give a 16 digit operand. The machine was later lost in an attic until 1879. Leibniz was also the coinventor of calculus. 1775 Charles, the third Earl Stanhope, of England, makes a successful multiplying calculator similar to Leibniz’s. 1776 Mathieus Hahn, somewhere in what will be Germany, also makes a successful multiplying calculator that he started in 1770. 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 calculator 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 intervals. Mueller’s attempt to raise funds fails and the project is fotten. 1801 JosephMaire Jacuard developed an automatic loom controlled by punched cards. 1820 Charles Xavier Thomas de Colmar (17851870), of France, makes his Arithmometer, the first massproduced calculator. It does multiplication using the same general approach as Leibniz’s calculator。 with assistance from the user it can also do division. It is also the most reliable calculator yet. Machines of this general design, large enough to occupy most of a desktop, continue to be sold for about 90 years. 1822 Charles Babbage (17921871) designed his first mechanical puter, the first prototype for the difference engine. Babbage invented 2 machines the Analytical Engine (a general purpose mathematical device, see 1834) and the Difference Engine (a reinvention of Mueller’s 1786 machine for solving polynomials), both machines were too plicated to be built (although attempt was made in 1832) but the theories worked. The analytical engine (outlined in 1833) involved many processes similar to the early electronic puters notably the use of punched cards for input. 1832 Babbage and Joseph Clement produce a prototype segment of his difference engine, which operates on 6digit numbers and 2ndorder differences (. can tabulate quadratic polynomials). The plete engine, which would be roomsized, is planned to be able to operate both on 6thorder differences with numbers of about 20 digits, and on 3rdorder differences with numbers of 30 digits. Each addition would be done in two phases, the second one taking care of any carries generated in the first. The output digits would be punched into a soft metal plate, from which a plate for a printing press could be made. But there are various difficulties, and no more than this prototype piece is ever assembled. 1834 Gee Scheutz, of Stockholm, produces a small difference engine in wood, after reading a brief description of Babbage’s project. 1834 Babbage conceives, and begins to design, his Analytical Engine. The program was stored on readonly memory, specifically in the form of punch cards. Babbage continues to work on the design for years, though after about 1840 the changes are minor. The machine would operate on 40digit numbers。 the mill (CPU) would have 2 main accumulators and some auxiliary ones for specific purposes, while the store (memory) would hold perhaps 100 more numbers. There would be several punch card readers, for both programs and data。 the cards would be chained and the motion of each chain could be reversed. The machine would be able to perform conditional jumps. There would also be a form of microcoding: the meaning of instructions would depend on the positioning of metal studs in a slotted barrel, called the control barrel. The machine would do an