1-10. AUTOMATIC MECHANICAL COMPUTERS
a. The Babbage Machines. The next breakthrough occurred in the early 19th
century, when Charles Babbage set out to automate the lengthy computations used by
astronomers in preparing math tables. Babbage, a math professor and eccentric
genius, occupied the same Cambridge University chair of math once held by Sir Isaac
Newton. Mathematical accuracy was a personal crusade with Babbage; he took
pleasure in spotting errors in the logarithm tables of astronomers, mathematicians, and
navigators. Observing that such calculations consisted of routine operations that were
regularly repeated, he envisioned a machine that could do the computations
automatically.
b. Babbage's Difference Engine (1823). In 1822, Babbage wrote a scholarly
paper describing an automatic mechanical calculating machine that could prepare
astronomers' math tables. It would be steam-powered, fully automatic, commanded by
a fixed instruction program, and even equipped with printouts of the resulting tables.
Babbage enlisted the support of the Royal Society, a prestigious association of
scientists, to obtain government grants, and spent the next 10 years wrestling with his
idea. By 1833, however, he abandoned it in favor of his next brainchild, the Analytical
Engine.
Figure 7-14. Babbage's Difference Engine, designed to calculate mathematical
tables, never left the drawing board.
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