Babbage's difference engine finally worked in 1991, 120 years after his death
Charles Babbage designed a mechanical calculator and a programmable computer in the 19th century but never saw either completed. In 1991 engineers built his difference engine from the original plans, using only tolerances achievable in his era. It worked. The man called the father of the computer had been right all along.
Even his birth is muddled. The Times obituary gave 26 December 1792, but a nephew insisted it was a year earlier, and a baptism entry of 6 January 1792 backs 1791. The son of a London banker, he was a sickly boy shuttled between schools and tutors, and discovered his love of mathematics in the library of a small academy in Enfield. By the time he reached Trinity College, Cambridge, in 1810 he had taught himself so much, reading Lagrange and Maria Agnesi, that the university's teaching disappointed him.
With John Herschel and George Peacock he founded the Analytical Society in 1812 to modernise British mathematics, and in 1816 they published a translation of Lacroix's calculus textbook. He also belonged to the Ghost Club, which investigated the supernatural, and the Extractors Club, pledged to rescue any member committed to an asylum. Despite being Peterhouse's leading mathematician he took a degree without examination in 1814, after defending a thesis judged blasphemous. He became a Fellow of the Royal Society in 1816 but lost several academic posts before inheriting about £100,000 on his father's death in 1827.
The engines grew from errors. Around 1821 or 1822, while he and Herschel checked recalculated astronomical tables for the Nautical Almanac, the discrepancies they found convinced him that calculation should be mechanised. The Astronomical Society, which he helped found in 1820, awarded him its Gold Medal in 1824 for his calculating engine. His later analytical engine contained the essential ideas of modern computers and took its programming principle from the Jacquard loom; he also designed the first computer printers.
His curiosity sprawled. He wrote on the economics of manufacturing in 1832, drew up actuarial tables, and with Thomas Colby argued for a uniform postal rate, adopted as the Penny Post in 1840. From 1828 to 1839 he held the Lucasian professorship at Cambridge while largely neglecting to lecture, and his Saturday soirées became fixtures of London society. He died on 18 October 1871; fragments of his machines are displayed at the Science Museum in London.
Source: Charles Babbage
