Joan Elizabeth Lowther Murray (nee Clarke) was a British cryptanalyst and numismatist and was well known for work as a code breaker at the Top Secret establishment Bletchley Park during World War 11.
Joan's education was at Newham College Cambridge, gaining a Double First, at a time when few women, ever went to university.
It was in 1940 Joan was recruited by academic Gordon Welchman who knew of Joan's abilities and wanted her to join his team at Bletchley Park. Joan was employed in Hut 8, and her use of Banburismus a cryptanalytic process developed by Alan Turing. This process reduced the need for Bomb Machine runs.
Joan Clarke had an exceptionally quick analytical mind, which did amaze some of her male co-workers, who were paid more than Joan because of their gender.
It was here at Bletchley Park...where Joan met Alan Turing, they had similar personalities and liked each other. Joan did become engaged to Turing, but later stated she did suspect he was an homosexual long before Turing told her. She also stated she was not alarmed by this, their relationship was more of a meeting of the minds. Which in their case, would be lasting and rewarding, to have someone of such similar interests as oneself. Clarke and Turing remained friends until his death, and frequently corresponded to each other.
In 1952 Clarke married John Kenneth Ronald Murray, and they had no children. Joan was at this time was working for M16 at GCHQ, where she worked until retiring at age 60.
Not possible to ascertain the exact work carried out by Joan at GCHQ, this being covered by the Official Secrets Act.
MBE (For Services At Bletchley Park)
British Numismatic Society
Sanford Saltus Gold Medal (1986).