/ 3 November 2000

Cogs of an inventor’s mind

Irwin Manoim

The Cogwheel Brain: Charles Babbage and the quest to build the first computer by Doron Swade (Little, Brown)

Had Charles Babbage been a little more even-tempered, a little less inclined to turn friends into life-long enemies, perhaps your great-grandmother would have grown up playing computer games.

Babbage invented a chess-playing computer more than a century and a half ago, when the industrial revolution had barely stepped beyond the potato fields. He also figured out the principles of modern computing down to the last nit-picking detail.

Unfortunately for your great-grandmother, not to mention the rest of humanity, the chess-playing computer was doomed to the same fate as every other Babbage invention: the head-strong inventor alienated potential partners, and not one device was built. The machines survive only as abstractions, buried in 7 000 pages of painstaking drawings, showing not only the parts, but their relative motions.

Babbage’s computers were entirely mechanical, driven by cogs, levers and rods. The more ambitious models could be “programmed” using punched cards. They had memory, which he named “the store”, and a central processor, which he called “the mill”. There was built-in error-correction. The chess-playing model could recall previous moves and learn from them. Results were automatically printed out – in neat columns and a choice of two fonts.

Babbage’s concentration wandered unpredictably, and along the way he designed a predecessor to Morse code (actually, it was cleverer than Morse code), central heating, a cowcatcher for the recently-invented steam train, the conveyor belt, and much more, generally considered amusing follies by his contemporaries. One of the few Babbage ideas to arouse enthusiasm in his lifetime was a mathematical proof that God’s miracles did not violate natural law.

In 1990, two centuries after Babbage was born, one of his machines was finally built. Doron Swade, an ex-South African who became assistant director of London’s Science Museum, spearheaded an ambitious project to build Babbage’s Difference Engine Number 2, a room-sized edifice of brass cogs driven by a hand-crank.

This book is Swade’s own tale of how Babbage’s drawings, housed in his museum archives, came to interest and then infatuate him, driving him to produce a machine to answer a 150-year-old riddle: would a Babbage machine actually have worked?

Number 2 was one of Babbage’s more modest proposals, a mere calculator by his standards, but the project taxed the best in 20th century technology for six years. Engineers consulted by Swane advised that no human would have the strength to turn the hand-cranked machine, and that many of the parts had no apparent function. The deeper the modern team probed, the more bewildered they became -parts of the drawings had been deliberately flipped, evidently a ploy by the paranoid old grouch to confuse any enemy who might steal his ideas.

In the end, Babbage – and Swade – were vindicated. The room-sized machine, like a vast, highly polished Meccano set, occupies star position at the museum. Modern audiences, made blas’ by an overload of electronic devices, are fascinated by the sight of thousands of brass gears dancing in silent harmony. A child can turn the equisitely balanced handle, and the parts with no apparent function turned out to be ingenious forms of error-correction.

There were several reasons why no Babbage machine was completed in his lifetime. One was that his designs, the most ambitious machines yet devised, stretched the limits of early-19th century craft. Another was that it was difficult for any sober-minded, rational contemporary to plausibly believe in a “thinking machine”. But the chief problem was Babbage’s personality.

As a well-connected Cambridge don, he wheedled government funding in 1823 to build a machine to automate arithmetic. His argument was that the navigation and logarithmic tables of the time were riddled with errors caused by human fatigue, and that only an untiring machine could guarantee error-free production of reams of statistics.

He engaged the finest metal workers in Britain, who slaved for a decade under his pernickety direction, producing some 12 000 hand-crafted cog wheels and levers. Then he quarrelled over money and his staff quit, leaving Difference Machine Number 1 less than half finished. Treasury officials were particularly annoyed, since they’d expected a working machine years before, and the budget had ballooned to 20 times the price of the average steam locomotive. There were questions in Parliament about a crackpot plan for a “thinking machine” and Babbage was never trusted with another penny in taxpayers’ money.

He might have recovered his position, and even persuaded someone else to build one of his later, more sophisticated machines, but he quarrelled with almost every important figure in the scientific establishment, stormed out of a meeting with the prime minister, and died unmourned in 1871, feuding to the last with his neighbours and a failure in the eyes of his contemporaries.

It took the late 20th century, in search of its own technological roots, to resurrect Babbage and convey upon him the belated title “Father of Modern Computing”. But the title is untrue. Babbage’s ideas died with him, and had to be reinvented a century later. His reputation for failure and money-squandering hung over the field for generations, blocking promising work on automation by other inventors.

Swade has produced an absorbing book, never allowing his own enthusiasm for Babbage to colour his views. Unlike his troubled hero, he writes with a simple clarity that pulls the reader into the drama from the first page. Nor does he take the obvious cheap shots at the 19th century scientists who were so blind to the far-reaching visions of the irrascible genius in their midst.