Aryan culture,Mavis decided that she didn’t want to read German poetry in Wales with a war on. Her first thought was to take up nursing but, encouraged by her professors, she went for an interview at the Foreign Office.
First of all I thought I was going to be a spy; then I thought it was going to be a job in censorship. In fact we weren’t allowed to be told what it was. We were just told it was very important. Initially I was at the Ministry of Economic Warfare opposite St James’s Underground Station, checking commercial codes, finding out who was supplying certain important minerals to the Germans. Then in summer 1940 I moved to Bletchley.
Mavis herself would have agreed with Doris that girls like her were privileged:
We were paid £2 10s a week, a guinea of which had to go on one’s billet. I lodged in a grocer’s shop, which meant I had bacon for breakfast! Later I was moved to a manor house, where I was waited on by a manservant who produced spam on a silver salver – but then the manservant was called up …
Well I absolutely adored the job. I was under the code-breaker Dilly Knox – we were quite famous in Whitehall as ‘Dilly’s girls’. In fact everyone was in at the deep end. There was no book you could read about the history of code-breaking, and there was no professor to consult.
Today, Dillwyn Knox’s contribution to the cracking of the Enigma code is recognised as having been crucial. Knox, an eminent papyrologist, had had a classical training and had studied literary papyri. He had the ability, and intuition, needed to recognise the metrical and rhythmic patterns of ancient poetry, and he brought these qualities to his cryptographic work. As Mavis explains, it was this approach that gave Knox the edge over a more mathematical system for code-breaking – and it was one that, with her literary background, she shared:
There are so many ways of setting an Enigma machine – millions and millions of them – that quite often the mathematically minded were reduced to questions of probability, as in ‘What are the chances of getting this out?’ But we just floundered in head-first and hoped for the best. One woman in my section dreamt the combination, and she turned out to be right! We worked by intuition, and strokes of imagination. But also, importantly, by psychology. For example, the Enigma machine has little windows, and you have to set the wheels to four different letters, and of course the operators were told to set them at random, but they never did. Instead they used dirty German four-letter words, or their girlfriends’ names. Well, we quite often knew our operators. So instead of having to work out the probability of what the setting of the wheels would be, we knew they had a girlfriend called Rosa, and it would work out. And so we built up all kinds of little tricks. Maths doesn’t really get you anywhere. It’s really much more like a game of Scrabble. You’ve got to have inspired guesses. And really that is a female quality.
To give you an example: Keith Batey, my husband, had trained to be a mathematician; we met at Bletchley. And I remember one occasion when I was tackling something. Keith looked over my shoulder and he said, ‘The chances of you getting that out are four million to one against you.’ Well at coffee time I walked over to him, and with the greatest of pleasure I told him: ‘That came out in five minutes.’
Mavis knew that her job was one of extreme importance but, ironically, it was rare that she was able to appreciate what a difference her work made.
You’re only given a part of the message to decrypt, and then it’s got to be translated and analysed, before they decide where it has to be sent on to: the Defence Ministry or the Admiralty or the Secret Service or what-have-you. There was the strict principle of ‘need to know’: you only knew what you genuinely needed to know, because if you’re captured they’ll learn the lot.
So we never knew
Rebecca Hamilton, Conner Kressley