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Comments, Queries and Debate: Babbage and the Colossus Disclosure Number: IPCOM000129573D
Original Publication Date: 1988-Jun-30
Included in the Prior Art Database: 2005-Oct-06
Document File: 2 page(s) / 16K

Publishing Venue

Software Patent Institute

Related People

Maurice V. Wilkes: AUTHOR [+2]


Computer Laboratory Cambridge, United Kingdom

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Copyright ©; 1988 by the American Federation of Information Processing Societies, Inc. Used with permission.

Comments, Queries and Debate: Babbage and the Colossus

Maurice V. Wilkes

Computer Laboratory Cambridge, United Kingdom

Much has been written about the work of Charles Babbage in the 19th century and the use, during the second world war, of the Colossus for code breaking. I would like to put these developments in their historical context as far as the modern computer field is concerned.

Charles Babbage, who went up to Trinity College, Cambridge, in 1810, had ideas for computing machinery that were much ahead of his time. It is important to distinguish two different machines that he proposed. The Difference Engine was intended to assist with the production of mathematical tables by performing the operation of subtabulation, one of the roles for which the National Accounting Machine was used in this century. The Analytical Engine, which Babbage proposed later, is of more interest since it was intended to be a general purpose, automatically sequenced computer. Babbage did not succeed in completing either machine, and an aura of failure came to surround his work.

The material published in Babbage's lifetime constituted a fairly comprehensive outline of his proposals, but the details remained hidden in his unpublished notebooks and drawings. It is only recently that these have been seriously examined by scholars (Bromley 1987). They are not easy to understand and are far from setting out a design that could be implemented.

Babbage was writing at a time when automatic machinery of any kind was uncommon. It s therefore not surprising that modern inventors of mechanical calculating machinery have followed different lines. However, Babbage must have enduring credit for being the first to conceive the idea of an automatically sequenced calculating machine and to describe means by which the idea might be realized. It is unfortunate that he did not publish his detailed work on adders and control mechanisms. This work would have had a real, if short-lived, relevance in the 1930s and 1940s when there was still an interest in mechanical, as distinct from electronic, calculating machinery. Probably he did not publish because he felt that he should first demonstrate, by building the Analytical Engine, that his ideas were sound. In this connection it is relevant to note that there is reason to believe that he never managed to arrive at a design for the control mechanism, or directive part as he called it, that he found sufficiently satisfying to regard as definitive.

Babbage was very conscious of his failure to build the Analytical Engine. He cursed his luck and blamed the world for not supporting him. His modern admirers have taken this up. The argument is: computers are successful in the 20th century; ergo, if the government had supported Babbage, then they would have been succ...