Old Westminsters at Bletchley Park

Memories of

I. John Croft CBE (Home Border, 1936-41)

In 1942, there were three OWW at Bletchley Park and one other associated with it; Bentley Bridgewater (later Secretary of the British Museum), Angus Johnstone-Wilson (later Sir Angus Wilson, novelist) and myself, then aged 19 and straight from Christ Church, Oxford. The other OWW were between 10 and 12 years older. Angus Wilson noticed I was wearing an OW tie, which led to a lifelong friendship. Lastly on the staff of the cryptographic training course at Bedford was J. R. Cheadle, then an officer in the Intelligence Corps and who, after the war, stayed on at G.C.H.Q.

The training course was devoted to hand or field ciphers – there was no mention of machine ciphers. When I was posted to Bletchley I was plunged into the most complicated cipher of the lot. This was the Lorenz Teleprinter, which had twelve rotors compared with Enigma’s four, and was only used by the German High Command and Hitler

himself. ‘Station X’ as it was known, or simply BP, was a mixture of civilians and service personal. At the time, and for many years after, one did not disclose to others what one was working on, but I subsequently ascertained that both Bridgewater and Wilson had been assigned to the naval section and were involved with the transmission of call signs by enemy ships and listening stations.

After six months at Bletchley I was transferred to the London outpost, located in Berkeley Street off of Piccadilly, and Aldford House in Park Lane. It was a relatively small team dealing largely with diplomatic i.e. non-military traffic. In war, it is advisable to watch your back as well as your front so we were also keeping an eye on neutrals and certain allies. After a few weeks struggling to break the Finnish machine cipher, I joined a new section to deal with the revived Soviet Comintern network of political agents scattered about Europe from Norway to the Balkans in advance of Russian armies, who communicated with Moscow using a hand cipher encrypted on a volume of Shakespeare.

The Comintern was kept separate from others and had no visitors. However, there was a common room at Aldford House and there, briefly, I met H.A.R Philby (OW) who was on the staff of MI6 and eventually defected to the U.S.S.R. Sometime in 1945 the Comintern network changed over to the use of One Time pads then considered more or less unbreakable. And so, with the European war at an end, I returned to Oxford to complete my degree. If there is a lesson to be learned from this experience, it is that the Cold War actually originated in 1943.