**The Best of Creative Computing Volume 1 (published 1976)**

Pascal's Arithmetic Machine Blaise Pascal-French mathematician, philosopher and writer-devised a calculating machine in 1642, at the age of nineteen. This machine demonstrated the practicability of mechanized calculation. Pascal's machine was operated by dialing a series of wheels bearing the numbers zero to nine around their circumferences. To "carry" a number to the next column when a sum was greater than nine, Pascal devised an ingenious ratchet mechanism that would advance a wheel one digit when the wheel to its right made a complete revolution. Answers appeared on indicators above the dials. Leibniz' Calculating Machine Gottfried Wilhelm Leibniz took the next great step forward in calculating machines. He wanted to mechanize the calculation of trigonometric and astronomical tables and free scientists for more fruitful work. "It is unworthy of excellent men," wrote Leibniz, "to lose hours like slaves in the labor of calculation..." In 1671, he started development of the first machine to multiply and divide directly. A version of this machine was built in 1694. Punched Card Looms Weaving looms in France were the First machines to be controlled automatically from coded information punched into paper cards. First proposed in the first half of the eighteenth century, the idea of using holes punched in paper to control the operation of a loom was perfected by Joseph Marie Jacquard in I804. He controlled the operation of a loom with a series of connected punched cards. The same basic technique is still in use in the textile industry. Babbage's Calculating Engines Over a century ago, an English mathematician named Charles Babbage was designing a machine based on the same basic principles as today's electronic computers. His first machine was a Difference Engine with which he hoped to mechanize the calculation of logarithmic and astronomical tables. Babbage built his first Difference Engine in 1822 (for which he won the first Gold Medal of the Royal Astronomical Society). It was a relatively simple machine that could generate tables to an accuracy of six decimal places. Then, he immediately began work on a bigger engine capable of twenty-place accuracy. Only part of it was ever constructed. After his work on the Difference Engine, Babbage developed new ideas for a really powerful tool to handle any sort of mathematical computation automatically. Powered by steam, this machine would have worked from a planned program of operating instructions stored on punched cards. It would have included, as modern computers now do, a memory or data storage section, an arithmetic unit, a section for entry of data and instructions, and an output section for printing 69