Your article on Alan Turing (Turings triumph, 15 November, page 7) mentions Lorenz and Colossus. The Axis developed a more powerful machine, Lorenz, to replace Enigma. Although the Lorenz code was broken at Bletchley by Bill Tutte, the solution was so complicated that it took days to translate a message, by which time the message was out of date. Bletchley attempted to construct a machine to translate a Lorenz message more quickly, but failed to do so. A General Post Office engineer, Tommy Flowers,, seconded to Bletchley from the Post Office Research labs at Dollis Hill, volunteered to construct a machine but was rebuffed by those in charge at Bletchley. Flowers, on his own, then designed and had built a machine to translate Lorenz messages at the Post Office labs at Dollis Hill. Flowers paid for many of the parts out of his own money and Colossus, the world’s first programmable electronic computer, was built at Dollis Hill. When Colossus, about the size of a room, was transported to Bletchley they were amazed to find that it could translate messages in minutes rather than days. Bletchley then commissioned Flowers to build other versions.
Colossus did extraordinary valuable work in translating Axis messages until the end of the war. It was regarded as so secret that Flowers was not allowed to mention its existence, and when the war ended could not get funding to proceed further – he had no proof that he had developed anything. For his pains, Flowers was given ￡1,000 in (part) recompense for his outlay in building Colossus, which he divided among his team at Dollis Hill. And that was all. There is a street named Flowers Close in NW2 and a Tommy Flowers building in Tower Hamlets, but I doubt that there are many who connect these with the man who designed and built the world’s first electronic programmable computer and who helped to shorten the second world war. So why no mention of Tommy Flowers?
Michael H Abraham
London
