Tommy Flowers

Thomas Harold Flowers MBE
Tommy Flowers - possibly taken around the time he was at Bletchley Park
Born	(1905-12-22)22 December 1905 Poplar, London, England
Died	28 October 1998(1998-10-28) (aged 92) Mill Hill, London, England
Nationality	English
Occupation	Engineer
Title	Mr
Spouse(s)	Eileen Margaret Green
Children	2

Thomas "Tommy" Harold Flowers, MBE (22 December 1905 – 28 October 1998) was an English engineer. During World War II, Flowers designed Colossus, the world's first programmable electronic computer, to help solve encrypted German messages.

Flowers was born at 160 Abbott Road, Poplar in London's East End on 22 December 1905, the son of a bricklayer. Whilst undertaking an apprenticeship in mechanical engineering at the Royal Arsenal, Woolwich, he took evening classes at the University of London to earn a degree in electrical engineering. In 1926, he joined the telecommunications branch of the General Post Office (GPO), moving to work at the research station at Dollis Hill in north-west London in 1930. In 1935, he married Eileen Margaret Green and the couple later had two children, John and Kenneth.

From 1935 onward, he explored the use of electronics for telephone exchanges. By 1939, he was convinced that an all-electronic system was possible. This background in switching electronics would prove crucial for his computer design in World War II.

Flowers's first contact with the wartime codebreaking effort came in February 1941 when his director, W. Gordon Radley was asked for help by Alan Turing, who was then working at the government's Bletchley Park codebreaking establishment 50 miles north west of London in Buckinghamshire. Turing wanted Flowers to build a decoder for the relay-based Bombe machine, which Turing had developed to help decrypt the Germans' Enigma codes. Although the decoder project was abandoned, Turing was impressed with Flowers's work, and in February 1943 introduced him to Max Newman who was leading the effort to automate part of the cryptanalysis of the Lorenz cipher. This was a high-level German cipher generated by a teletypewriter in-line cipher machine, the SZ40/42, one of their "Geheimschreiber" (secret writer) systems, that was called "Tunny" by the British. It was a much more complex system than Enigma; the decoding procedure involved trying so many possibilities that it was impractical to do by hand. Flowers and Frank Morrell (also at Dollis Hill) designed the Heath Robinson, the first machine designed to decrypt the Lorenz or “Fish” machine cyphers.