Secret Days: Code-breaking in Bletchley Park Asa Briggs

Frontline Books, 5 Accommodation Road, London NW11 8 ED, Tel: 0208 455 5559, pp.202, 19.99

The story of Bletchley Park, MI6’s second world war code-breaking operation, has grown with the telling since the early 1970s accounts — although, as Briggs points out, Bletchley’s first public disclosure was in Time magazine in December 1945.

The story of Bletchley Park, MI6’s second world war code-breaking operation, has grown with the telling since the early 1970s accounts — although, as Briggs points out, Bletchley’s first public disclosure was in Time magazine in December 1945. In recent years it has become the stuff of fiction, film and feature, and almost anyone who was there and is still alive is guaranteed a publisher. Aged 90, Asa Briggs — distinguished historian, former chancellor of the Open University and vice-chancellor of Sussex — was there and is very much alive, as this gossipy and informative account shows.

Most of us can only guess what it must be like to be effortlessly clever at everything. A grammar school boy from Keighley, Briggs won a history scholarship to Sidney Sussex, Cambridge, where he might just as easily have read maths. While completing his tripos he secretly did an external London BSc (Econ), on the strength of which he was offered an LSE fellowship. But there was a war on, so he joined the army as a private and soon found himself at Bletchley, where he met others as clever as himself.

Some he knew from Cambridge and in this account he carefully notes the colleges, universities and schools that contributed to the informal military-civilian senior common room that Bletchley became. There were plenty of women and Briggs implies — discreetly, of course — that it was not only his intellectual horizons that were broadened.

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But it wasn’t all good talk and fun: they worked hard, in shifts, around the clock, often in inadequate conditions, on a limited diet and with living quarters that could be anything but comfortable and convenient. Popular accounts often ignore the fact that many, like Briggs, were in uniform. Although rank was of little or no consequence at work, he lived off-site at an army camp where he was subject to normal military discipline (early morning PT, for example). Could he be the only vice-chancellor to have held the rank of regimental sergeant-major?

Briggs rightly stresses the decisive contribution of Gordon Welchman to Bletchley’s informal, flexible, results-focused culture, placing him above (in that respect) Alan Turing and Dilly Knox. Many others are mentioned, including some whose contributions were fundamental but who remain relatively little known, such as John Herival (author of the Herival Tip, which dramatically narrowed the number of likely ring settings an Enigma operator might employ), Donald Michie and Colonel Tiltman, ‘a giant among cryptographers’.

Anyone infected with management blight will be horrified to read that there was no formal organogram of Bletchley until 1944; others may see that as one reason for its success. As the war went on, rules, formalities and processes proliferated and Bletchley doubtless became more efficient in terms of product delivery, task allocation and administering itself. But there seems equally little doubt that it was from the early flexibility of recruitment and who-did-what that the great achievements flowed. People’s energies went into doing what they were there for, not into what they were called or paid or where in the structure they were. Off duty, they played hard: sport, amateur dramatics and a great deal of poetry.

Briggs’s familiarity with other accounts strengthens his own, particularly in terms of his perspective. Granted, there’s sometimes too much detail about people we don’t know — ‘Subsequently he went on to join the British Council in Portugal, where a close girlfriend of mine also went’ — but that is the forgivable indulgence of memoir, easily outweighed by information about the work itself. I hadn’t realised that a simpler version of Enigma was broken during the Spanish Civil War, nor that Colossus (the world’s first computer) was deployed not against Enigma but against sophisticated teleprinter cipher systems called Fish, one of which — Tunny — carried important signals between Berlin and German army commanders. The techniques involved, including binary maths, led to what we now call the digital age.

Most breakthroughs came not from cryptographic insights or bombes (electromechanical machines operated by Wrens) but from operator error, broken Enigma keys being recorded in the Fracture Book. It was pleasing to see acknowledgement of Typex, the cipher machine MI6 used to carry (amongst much else) the Enigma decrypts, itself a development of Enigma (yes — we had it, too, only no one knew it). Pleasing, too, to see mention of the work against Japanese ciphers (you were given six weeks to learn the language), acknowledgement of the crucial role of wireless intercept and to learn that Ian Fleming was a frequent — but discreet — visitor.

I was once told by someone from GCHQ, Bletchley’s successor, that you could read everything released or published on Enigma yet still be unable to break it. Even in this age of computer-generated rather than machine ciphers, some details remain undisclosed. Briggs more or less confirms this, noting that ‘there are still secrets of BP that are not being released’. That, too, is a pleasing thought and a fitting end to this fascinating and insightful account.

This article first appeared in the print edition of The Spectator magazine, dated

Tags: Bletchley Park, Book review, History, Mi6, Non-fiction, Wwii