TWELVE

Farewell

My most enduring memory of Dilly is of staying at Courns Wood in his last spring. He had invited me over to see the ‘loveliest of trees, the cherry now’ in full bloom under the guest bedroom. He was still passionate about his trees and I learned a lot about the Chiltern woodlands that weekend; but it could no longer be the strenuous planting or sawing and splitting of wood he so loved to do. I just helped him shake pine cone seeds into tobacco tins for scattering. I hope my efforts for posterity have come to maturity in the Naphill woods. Flourishing outside the village hall was the Atlantic cedar he had planted for the celebration of King George VI’s coronation in 1937. Today it is lit up every Christmas.

While Olive was getting the supper Dilly got out the photographs of the Mimiambi fragments from the Greek papyri and showed me how he had put them together. At least we had a table to spread them out on and one can only wonder how he managed to do it on his knees on the train from High Wycombe to London and the reaction of his fellow commuters reading their newspapers.

Olive had greeted me with an apology that the laundry hadn’t come and would I mind sleeping in Ronnie’s sheets as he had just left. Dilly added that it was all right to do so because he was very clean. Ronnie had not come to see the cherries ‘hung with snow’ as he could have his fill of them in Housman’s own Shropshire, where he was living in a convent engaged in translating the Bible into English for Roman Catholics. It was this on which he had been consulting Dilly, as he had just got to the Epistles and for St Paul’s visit to the Corinthians, and he too was battling with Greek papyri. Dilly said he had translated more of it than Ronnie as his brother’s Greek was not up to standard. He felt that Ronnie ought to know more about the Corinthians and their way of life in the same way in which he had sought out the world behind Herodas when editing his mimiambics. He had also tried to steep himself in the German mindset when coming to terms with the Abwehr.

Churchill had perceptively assessed, when referring in 1919 to Room 40’s successful codebreaking, that it had needed ‘a study of the psychology of the persons sending out the messages and a sort of instinctive “flair” for the kind of things they are saying’, which was different from ‘intelligence analysis’. Dilly had been able to take his time reading the stacks of ISOS hand cipher messages shown to him by Oliver Strachey before he broke the Abwehr Enigma and had got a good idea of the psychology of the spy people he was dealing with. Psychology had taken on a new dimension since Freud. The sixpenny Pelican series had produced his Psychopathology of Everyday Life just before the war and we were all into the subconscious and Freudian slips. I enrolled for the Cambridge extra-mural psychology course being given in the town as soon as I arrived at Bletchley and felt one up on everybody else as when I was at Zurich University I had heard Freud’s disciple, Carl Jung, lecture.

We pursued our operator’s subconscious when setting up his supposedly random indicators. Settings which could be guessed from idiosyncrasies of the operator became known as ‘psillis’ as an extension of Dilly’s cillis, which were more attributable to the conscious slackness of the operator than determined by his subconscious. As the Abwehr had four-letter indicators there was much more Freudian scope for codebreakers. Girlfriends of course were an obvious giveaway and ROSA with her in-built lobster was a friend indeed. I became an expert in four-letter dirty German words and was dismayed when one day there was a reprimand from Berlin to operators for using obscenities when young girls were having to decode them. They meant the German girls of course, not us. Needless to say, we were furious when they were abandoned. We were prepared for anything with the Abwehr indicating systems.

Sometimes it was a new cipher boss who made life difficult for us. One, von Bentheim, decreed that in future indicators should be encoded half at a Grundstellung and half at a setting of a German folk song, for which my German romantics had fortunately prepared me. Sometimes the indicators had to be scrambled so that ROSAZ ROSAZ on a given key 5332142514 would be encoded at the Grundstellung as ZSSORAOZRA, which played havoc with boxing. It made us quite dizzy and we called it ‘jitterboxing’ after the new jitterbugging dance that the Americans had just taught us. I think we could rightly say in ISK that, to our knowledge, in machine cryptography our problems for variety and novelty were unequalled. We were prepared for anything, however bizarre.

There was worse to come in the summer when the Abwehr suddenly got round to realising the folly of using double indicators on a fixed Grundstellung, which the services had abandoned as long ago as 1938. Gone was boxing altogether, and our lovely chain-lobstering, when faced with single indicators; new methods for textual breaks for multi-turnover machines had to be made, involving making new catalogues and even our own bombe. Peter Twinn had worked with Alan Turing on the Letchworth bombes for Hut 6 and Hut 8, but if we were to have one made for our Abwehr machine it would need to have an additional electro-mechanical counter to account for the Abwehr machine having a moveable Umkehrwalze. Peter went to show the proposed diagram to Dilly and came back with a special name for it – Fünf, after Tommy Handley’s German spy in the hilariously popular radio comedy ITMA, then all the rage. Fünf was in action by November and Jean Hazlerigg took charge of our Spy Enigma menus for the Wrens in the Bombe Hut to set up when all other methods failed.

There was still much hand-work to be done before resorting to programming Fünf and Twinn produced a blackboard and asked me to explain the new method to the girls. We had had to take on more staff who had never heard of Enigma before and even someone who had worked on the old system said that she had never understood what it was all about as she just got on with following Dilly’s simple instructions of how to do it, so why bother about explaining new theories when she didn’t need to know the old? I must have told Dilly, who was still deep in Ronnie’s epistles, about my frustrations, as I have a letter back from him saying:

There is a lesson from Corinthians for you beginning: ‘If after the manner of men, I have fought with beasts at Ephesus’ that would appear apt enough for your efforts to teach the newcomers. A little further on we have the famous proof of the resurrection, ‘if the dead rise not, then is our teaching in vain’, which is a form of argument which can be paraphrased to meet all hecklings as you will see.

The hecklers were right, of course; in ISK you could drive the car perfectly well without knowing what went on under the bonnet. Later, when Keith Batey joined us permanently, he tried to give a newcomer a tutorial on how the machine worked technically and afterwards she fled, never to be seen again; it was rumoured she had had a nervous breakdown.

Dilly was very anxious that I should meet his niece, Penelope Knox, to try and persuade her to leave working for her father at Punch and join us in ISK. However, I did not actually meet her until 1975, when she had begun to write her biography of the Knox brothers. Naturally she would have liked to have known about Dilly’s wartime work and thought that all could now be revealed after Frederick Winterbotham’s book on Bletchley Park had been published in 1974. We had been told that it was now permissible to be anecdotal but on no account to give technical details of codebreaking in interviews, so we could not be much help; nor could Margaret Rock or Peter Twinn. It was only in 1982 that Gordon Welchman wrote his book on Hut 6 giving technical details of the breaking of Enigma. However, Penelope’s husband paid a visit to Gustave Bertrand, whose book Enigma had been published in 1973, and he was able to furnish her with details about Dilly’s visit to Warsaw and other contacts he had had with him. Unfortunately, Bertrand, who was no cryptographer, also offered to explain ‘the early stages in the solving of Enigma’, which he had never understood, and Dilly must have turned in his grave to see the resulting description of his work as recorded by Penelope.

It was decided that we must recruit some newly graduated mathematicians to join the team, at least one of whom would become a professor in later life. Dilly insisted that I should be present at the interviews, not to check their capabilities, as that would be taken care of, but to see if these males were the sort of people the girls could get along with. By then I had confessed that I had become engaged to the ‘wranglercove’ Keith Batey and although Dilly congratulated me heartily, he asked me if I knew that mathematicians as a breed were not usually very imaginative. I reassured him that this one was all right. When I showed Olive my engagement ring and it transpired that I had chosen it myself, she told me that Dilly had bought hers himself and given it to her in Room 40 as he thought that was what the bridegroom was meant to do. By the tone of her voice I rather detected that she too would have preferred to have been in on the choice.

Dilly wanted to hear about the visit of the Americans to see how our Abwehr machine worked. I told him that two service types came, one large and bullying with two ribbons and the other lean and acquiescent with one. After five minutes, the leader said: ‘We’ve sure got your machine taped now,’ which of course he hadn’t. The other one made what we thought was quite an intelligent observation to be crushed by ‘Don’t be ridiculous’ and he said meekly: ‘Sorry, it was only an idea.’ He awoke our maternal instincts and as we had managed to get the ingredients for a chocolate cake together, which we baked in the kitchen for their visit, we made sure he was given a much larger piece. When they left they said that they had never had such hospitality, nor met such charming people. My note ended: ‘I hope we are not going to have a whole string of Dough-boys to drive dizzy.’ I think it was the lack of hierarchy that amazed all the Americans. Anybody, however junior, with a bright idea was listened to in ISK and often it worked. William Friedman, America’s top codebreaker, on a visit to Bletchley Park in 1943 was astounded at what he regarded as a bunch of amateurs could produce. ‘In a technical sense, we are ahead,’ he said. ‘But in a practical sense, judged by accomplishments, these amateurs have very largely surpassed us in detail, attention to minutiae, digging up every bit of intelligence possible and applying high-class thinking, originality and brains to the task.’

Admiral Godfrey made a point of visiting Courns Wood as often as he could to tell Dilly how strategic deception was being planned as a result of his Abwehr break, now that Torch, the first Allied operation, was scheduled for the autumn; this was something which was not known to the staff in ISK itself of course, where to us it would just be action stations jumbo rush when it happened. On one occasion, Dilly told Godfrey that he was sure he would get better if he had a cruise and asked him to try and get him on an Arctic convoy; the astounded admiral could only say that these were not vessels to recuperate on. We knew Dilly had said he wanted some sea air and thought he just meant a yachting trip on the Fal with Frank Birch as in the old days, but alas not even this could take place. Peter Twinn and I continued to visit Courns Wood regularly to keep Dilly informed of ISK progress and were taken by official car. There was one driver who seemed to think we were out for a joy ride and was determined that we should see all the sights of Buckinghamshire – Chequers, Ishbel Macdonald’s pub and some speed trials, but we told him not to waste time and petrol and take the shortest route.

At this time, Margaret Rock had for several months been working with Dilly at Courns Wood on an ‘isolated problem’ which was not connected with Abwehr. She was able to drive Dilly over, sometimes bearing lovely fruit, which we ate in the garden at Elmer’s School. She was very secretive about the work but as it had no bearing on ours we knew better than to ask her. It has been suggested that Dilly was working on Soviet ciphers before he died and this may well be true. Russia was our ally and officially we had ceased to read their traffic, but in March 1942 ‘C’ and the director general of the security services decided that some Russian systems should be worked. Dilly had of course worked on Comintern and with the great Russian codebreaker, Ernst Fetterlein, and it might have been the answer to let him work on it away from mainstream codebreaking. Margaret and I went on to work on Russian at Eastcote after the war. But ‘need to know’ was just as strict then and I did not ask her if that was what she and Dilly were doing in 1942. Margaret Rock did come back to hold the fort for the jumbo rush before Operation Torch when Keith and I were married in London with Peter Twinn as best man. Dilly sent us a lovely wedding present and said that if the Muse hadn’t left him he would have composed my wedding hymn.

Soon afterwards Dilly was admitted to University College Hospital and when I visited him his brother Evoe was by his bedside and they were roaring with laughter composing Dilly’s last words. They were reading from a book of collected famous last words called The Art of Dying, which Dilly handed to me when I left. I still have it. Dilly’s last words were in fact: ‘Is that Ronnie outside in the corridor bothering God about me?’ He wrote a pentelope for his epitaph:

A wanderer on the path [A]

That leads through life to death, [E]

I was acquainted with [I]

The tales they tell of both [O]

But found in them no truth [U].

Dilly died at home on 27 February 1943, aged fifty-eight, and was buried in his woodlands, where Olive’s ashes would later be scattered. John Maynard Keynes, who was present, described his old friend as ‘sceptical of most things except those that really matter, that is affection and reason’.

Just before he died, Dilly was appointed as a Companion of the Order of St Michael and St George ‘for services to his country’. It was explained to Olive that security conditions precluded a more illustrious honour. Dilly insisted on getting dressed to receive the emissary from Buckingham Palace and, typically, he sent the decoration to ISK with a touching note saying it was really meant for them. It was heartening to know that he regarded ISK and what he called the ‘Cottage tradition’ as the fulfilment of his career. The official farewell letter shows that, until the very last moment, he was insisting that codebreaking and intelligence work were inseparable and that the secrecy of ‘need to know’ and ‘working in blinkers’ was counter-productive. His letter ended: ‘In bidding farewell and closing down the continuity but not, I hope, the traditions of the Cottage, I thank once more the section for their unswerving loyalty. Theirs I remain

Affectionately

A. D. Knox.’

 

Courns Wood

Hughenden

Bucks

Jan 3, 1943

 

Dear Margaret [Rock]

Mavis [Batey]

Peter [Twinn]

Rachel etc.

[Denys] Page

Peggy [Taylor]

 

Very many thanks for your, and the whole section’s, very kind messages of congratulations. It is of course, a fact that the congratulations are due the other way and that awards of this sort depend entirely on the support from colleagues and associates to the Head of the Section. May I, before proceeding, refer them back.

It is, I fear, incumbent upon me at the same time to bid farewell. For more than ten years, I have taken up with A.G.D. the position that (a) there is no proper distinction between research cryptography and cipher and intelligence work, (b) that it is as improper to ask a person of any degree of education to run a key-setting bureau, as to ask him or her to run a typewriting section, (c) that it is impossible to edit or translate satisfactorily without a precise knowledge of the cipher in question, (d) latterly we have recruited during and shortly before the war from the Universities; and Academic tradition does not understand the idea that a half-fledged result should be removed from the scholar who obtains it and handed over to another. The discoverer loses all interest in further discovery and the recipient has no interest in the offspring of another’s brain. Still more doubtful is the case of ‘Research’. Until we know who will handle and circulate any result we get, the irrepertum aurum of our search will very probably be sic melius situm.*

I have recently arranged with the authorities to attempt a line which should give wider scope though it will be of far less importance. In bidding farewell and in closing down the continuity but not, I hope, the traditions of the Cottage, I thank once more the section for their unswerving loyalty. Theirs I remain

Affectionately

A. D. Knox

The original letter, written in green ink on blue paper, an old naval tradition, can be found in The National Archives (Public Record Office) HW 25/12

 

* The Latin is a quote from Horace, Odes III, 3, 49, irrepertum aurum et sic melius situm – ‘the gold unfound and so the better placed’.