Harold Keen

Harold Hall "Doc" Keen (1894–1973) was a British engineer who produced the engineering design, and oversaw the construction of, the British bombe, a codebreaking machine used in World War II to read German messages sent using the Enigma machine. He was known as "Doc" Keen because of his habit of carrying tools and paperwork in a case resembling a doctor's bag. After the war he was awarded the O.B.E..

Career before World War II

Keen was born in the borough of Shoreditch in east London in 1894. By age 18 he had moved to Kentish Town and began studying Electrical Engineering. In 1912 he joined the British Tabulating Machine Company (BTM), established to import and assemble American punched card technology. In 1916, Keen joined the Royal Flying Corps and was assigned to the ground staff of a bomber squadron in northern France. In 1919 he returned to BTM and married an Eva Burningham. In 1921, Keen moved with BTM to Letchworth in Hertfordshire. Two years later, he was appointed head of the Experimental Department, and his innovations there gained him the reputation as the leading British innovator of punched-card technology; Keen was granted more than sixty patents. In the 1930s he became Chief Engineer.

References

• Keen, John (2003), Harold 'Doc' Keen and the Bletchley Park bombe: Code name CANTAB, Kidderminster, England: M. & M. Baldwin, ISBN 978-0947712426

See also

• Cryptanalysis of the Enigma
• Joseph Desch was research director of the project to design and manufacture the US Navy version of the bombe during World War II