Secret Life of Bletchley Park - McKay Sinclair [46]
It was the first sign of serious friction at Bletchley Park. While it could hardly be said that the three services – army, navy, air force – were in competition, the fact was that some codes were being broken with reasonable success whereas others – the German naval codes – were still proving resistant. As a result, it was felt that the British navy was not getting the vital intelligence it needed.
Although during the Battle of Britain in mid-August, the emphasis was very much on air force intelligence, Frank Birch, head of the German Team of the Naval Section at Bletchley Park, wrote a memo to Edward Travis, Deputy Director of the Park:
I’m worried about Naval Enigma. I’ve been worried for a long time, but haven’t liked to say as much. .. Turing and Twinn are like people waiting for a miracle, without believing in miracles …
Hut 8 has not produced any results at all so far … Turing and Twinn are brilliant, but like many brilliant people, they are not practical. They are untidy, they lose things, they can’t copy out right, and dither between theory and cribbing.4
There might have been something in Birch’s complaints – Jack Copeland later stated that Turing was extremely bad at making himself understood – but in a wider sense, the complaints were unfair, as would become clear as the months progressed. Thanks to the stringency with which naval Enigma was employed, including the use of bigram tables, it was far harder to break than the military and Luftwaffe Enigma codes worked upon in Hut 6. The only reasonable chance Turing and his Hut 8 team had of cracking naval Enigma would be if one of these books of tables were to be captured.
In the meantime, there was yet another breakthrough. Turing and Welchman saw that their ‘diagonal board’ feature could allow for simultaneous scanning of all the possible twenty-six plug-board settings for an individual wheel setting. ‘Agnes’ – an abbreviation of its real name, Agnus Dei, the sister machine to Victory – made her debut in August 1940 in Hut 11. Once both machines had been fitted with the diagonal boards, they were truly operational. One veteran recalled: ‘The bombes were bronze-coloured cabinets about eight feet tall and seven feet wide. The front housed rows of coloured circular drums – the naval colours were dark blue, black and silver.’
‘After the first two, a large number of machines were made to a fairly standard form,’ says Oliver Lawn. ‘It proved its use. Altogether about two hundred were made. The first ones were located at Bletchley itself, in what is now called the Bombe Room, which still exists. But when the numbers grew bigger, they had to use other places, and as the war went on, most of them were put at two locations in north London – Eastcote and Stanmore. They had roughly a hundred machines each, run by a large company of Wrens in both cases.’ The reason for the multiple locations was simple: the threat of bombing. To have such precious and irreplaceable machines working in a single location would have been unthinkably risky.
The very first Wrens, eight of them, made their appearance at Bletchley Park in 1941. They were there to see if it was possible for young women to work the bombe machines. Some senior men held the view that ‘it was doubted if girls could do the work’. They were not merely being sexist; it was perfectly reasonable to wonder if such young people would indeed be up to the remorseless, ineluctable pressure of the job. However, clearly the Wrens were up for it. And as throughout the war the number of bombe machines crept up to a total of 211, so too did the numbers of Wrens. One estimate suggests that by 1945 there were 1,676 bombe operators. The effect of the work on those early Wrens, though – and indeed, among the many who were to follow – was often deleterious.