- Shopping Bag ( 0 items )
From Barnes & NobleThe Barnes & Noble Review
Computers weren't always made of silicon: For centuries, they were made of flesh and blood. Real human beings, called "computers," sat from morning until night, making calculations. One day in 1821, Charles Babbage and his friend the astronomer John Herschel, sat down to review hundreds of those calculations -- and quickly discovered errors that spoiled them beyond repair.
Said Babbage, "I wish to God these calculations had been executed by steam." And so began two obsessions: Babbage's lifelong, failed project to construct a working digital computer, and the London Science Museum's quest to build the computer Babbage could never finish. Both are chronicled splendidly in The Difference Engine.
Doron Swade, who masterminded the Science Museum's project, begins with Babbage himself -- a man who was brilliant and stubborn in equal parts. Babbage left Cambridge without his degree, having chosen a "blasphemous" proposition to defend in the public debate that would've qualified him to sit for final exams -- knowing full well that he was to be judged by a leader of Cambridge's religious community. His principled contrariness would be the hallmark of his career, ultimately alienating the political and financial supporters whose help was essential to the completion of the project.
For all that, Babbage did manage to create plans of breathtaking complexity that would have required 25,000 individual parts. Many of the calculating components were actually built -- painstakingly, one at a time, since mass-production techniques with the needed precision didn't yet exist. (Tragically, most of these items were later melted for scrap.)
Some may be discomfited by the book's assessment of Ada Lovelace, Lord Byron's daughter and Babbage's collaborator. She is often credited with outlining the key ideas that led to the modern discipline of computer programming; Doron Swade objects. "The notion that she made an inspirational contribution to the development of the Engines is not supported by the known chronology of events.... Historians close to the detail of Babbage's work express dismay at the well-intentioned but misguided tributes paid to Ada."
Some 150 years after Babbage failed, Swade and his colleagues picked up where Babbage left off. The original plans would challenge them nearly as severely as they had Babbage. Putting aside the financing issues that complicated construction of Babbage's Difference Engine No. 2, there were design issues as well. Swade's team found small problems ("a long, beautiful, helical arrangement of arms which performs no function at all") and a few larger ones -- notably, a defect in the mechanism for carrying tens that Babbage would certainly have noticed had he ever built it.
Through 1991, the team gradually improved the clanking machine's reliability, reducing the frequency of jamming -- and of problems that would send broken bronze parts shooting across the room. On November 29, 1991, the engine performed its first full, automatic, error-free calculation.
If you're in London, you can see Babbage's engine today. But seeing it only hints at the richness of his vision. To really understand the dream -- and how it became real -- you need to read The Difference Engine. (Bill Camarda)
Bill Camarda is a consultant, writer, and web/multimedia content developer with nearly 20 years' experience in helping technology companies deploy and market advanced software, computing, and networking products and services. His 15 books include Special Edition Using Word 2000 and Upgrading & Fixing Networks For Dummies®, Second Edition.