Dilly

by Batey, Mavis;

  As ever, Denniston attempted to mollify Dilly, pointing out that the arrangement of 5 December merely reinforced the GC&CS tradition that the various specialist sections processed the decodes for their own areas. Hut 3 processed German air force and army Enigma; the Spanish naval attaché messages originally broken in the Cottage were processed by the Spanish naval section; the small amounts of German naval Enigma that had been broken so far had been processed by Frank Birch’s German naval section. None of them could have done anything without the work put in by the codebreakers led by Dilly’s research section in the Cottage.

  So far as the Italian Naval Enigma is concerned, I cannot understand why you should wish for an alteration of the practice. Clarke deals with the circulation of all this [Italian] traffic of which the Enigma forms a part. He dealt with it in pre-war days when you first broke into the machine. If the duty were given to Hut 3, it would be necessary to find Italian speaking staff to work there and to study the contents, in fact to duplicate the work which Clarke’s section already does. So far as the personal side is concerned I hope you do not underrate your own position. It is obvious that the Research side of Enigma, which, you direct, has met with very considerable success, and it must be perfectly clear to you, to all those concerned in GC&CS and to the recipients of the decodes that without the Cottage and Huts 6 and 8 there would be no Enigma traffic. This is my view; I cannot, therefore, see any reason why the existing methods of circulation should be changed.

  But Denniston’s insistence on the status quo did not suit Dilly, who wanted to have a finger in the intelligence pie, his permanent complaint being that ‘there is no proper distinction between research cryptography and cipher and intelligence work’. By January 1941, a solution had been found and it may be one of the occasions Clarke had in mind when he said that

  Dilly was a genius in cryptography as well as in other matters but he was very temperamental and had to be handled tactfully or else he refused to play; I happened to be one of the few people who understood how to manage him and when these clashes occurred I was called in to restore peace and ward off the resignation which he threatened.

  Clarke was able to cope tactfully with the Italian crisis in a way which suited all parties. His intelligence officer, Commander Charles O’Callaghan, who had been with him in the Italian naval sub-section for some time, had been transferred to the Admiralty. Clarke now managed to get him back as an Italian expert and made him liaison officer to Hut 3. Intelligence derived from codebooks and hand ciphers would be passed to Hut 4 as usual but Italian Enigma intelligence would go straight from the Cottage to Hut 3, where Dilly would have direct access to O’Callaghan. There were very few Italian naval Enigma messages for the Cottage to deal with for the first few weeks to enable us to produce crib charts to speed up the rodding technique. However, submarines seemed to be the order of the day and a ‘sommergibili chart’ was made for all possible clicks, sommergibili being Italian for ‘submarines’. We pronounced sommergibili in a very English way with the emphasis all in the wrong place. No doubt Dilly knew what it was all about but his belief that there was intelligence he did ‘need to know’ did not naturally extend to his staff and I have only found in recent records that we were dealing with the Italian invention of the midget submarine on which two sailors had to sit in divers’ suits. The first use of them was when two attacked Gibraltar in October 1940 and our messages gave the first knowledge of them. They were carried on the exterior of a full-size submarine or vessel and launched near the target. Having now seen photographs of them it is small wonder that the poor sailors forced to sit astride them detested them and called them ‘swine’.

  The Italian fleet itself seemed reluctant to make an appearance, but in early March 1941 the Germans made it clear that something was expected of the Italians in the way of hindering what we called Operation Lustre. British and Australian troops were being sent to our ally Greece from north Africa at regular intervals after the failure of the Italian invasion and Admiral Cunningham, as Commander-in-Chief Mediterranean, was given the additional task of taking charge of the convoys. Hut 3 received a decoded Afrika Korps Luftwaffe message of 21 March 1941 revealing that German fighters were being flown to Palermo to provide cover for a special action and immediately alerted Dilly to be on the lookout. It was essential for Cunningham to know where and when this was to take place; with the fleet stationed in different places he needed ample warning to overcome the distances in the Mediterranean. Knowing the day the operation would start was essential and the Cottage, which was on red alert, soon discovered it for him.

  Fortunately, we had broken the new wheels the Italians had introduced and, although there were now six possibilities for rodding and charting for the right-hand wheel, it did not take us long. Dilly had rounded up all those members of the Cottage staff who had been seconded to Hut 6 and Hut 8 during the slack period and on 25 March we broke a signal which said quite simply, with the minimum of topping and tailing, ‘Today is X-3,’ but even in such a short message the operator had inserted three full stops. Our XALTX charts were put to good use and, as Dilly quipped, success added a new meaning to the word exaltation. We went round chanting: ‘Today’s the day minus three.’ We waited anxiously all night for the dispatch rider from the ‘Y’ intercept station and stayed at our posts for the days leading up to the Italian intervention. Finally, in the late evening when we could do no more, I made my way down to the station in the hope of getting a train to Leighton Buzzard, where I was billeted. I found the Royal Scot taking on water and went up to the driver and asked him if he could give me a lift. ‘I’d do anything for you, Missie,’ he said, ‘but I’m afraid the train can’t get into Leighton Buzzard.’ I think I fell asleep on Bletchley station until the milk train came through. Dilly made sure that I was moved to a local billet in readiness for the next crisis.

  It had indeed been a marathon. Each day had a different key setting and each message had to be broken separately. XALTX could not always be relied on to produce clicks but we also had crib charts for Supermarina, Inglese, and incrociatore (cruiser). Claire Harding was responsible for organising the shifts and seeing that all possibilities were covered and that the rods were not left lying on desks but put back in the right jam jars. Although it was unlikely that Bletchley Park received any of the instructions sent direct to the Italian fleet, Supermarina repeated them to the commander in Rhodes on the Enigma machine, and these were intercepted. EGEOMIL, the official title of the commander on Rhodes, became a good friend and a very useful crib. The Rhodes messages that reached Cunningham enabled him to make his battle plan in good time but in his Sailor’s Odyssey, which he published in 1951, he was not able to disclose any secret sources. That the important one was given special ULTRA treatment, thanks to Dilly, was vividly described by his flag officer, Captain Hugh Lee, in 2001:

  I was working in my tiny cabin in HMS Warspite, the Fleet Flagship, on 27 March 1941, when the Royal Marine orderly told me I was required in the Admiral’s Staff Office, only a few yards away. On arrival, I was handed a signal by the Staff Officer Operations and told to put the positions given in the signal on the strategic chart, which I kept in the Admiral’s dining cabin, and as soon as I had done this to bring the signal straight back to him ‘under pain of death’. Naturally I did as I was told! I did notice that the signal was marked ULTRA but I did not have the faintest idea what it meant. Security and secrecy were paramount. At 11 am a meeting of the Commander-in-Chief’s operational staff was called in the cabin and Admiral Sir Andrew Cunningham explained to the Staff that ‘reconnaissance’ had sighted a strong force of the Italian Navy, including Mussolini’s pride and joy, the battleship Vittorio Veneto, steering towards the Eastern Mediterranean. He suggested that they might have one of three aims and he asked the staff to return at 2 pm and give him a consensus of what they thought was the aim of the Italian Force. At 2 pm (the timing had been carefully worked out by those in the know) the staff returned and their unanimous opinion wa
s that an attack was planned on the British military convoys carrying troops from Alexandria to Piraeus in Greece. The Commander-in-Chief concurred in their judgement and ordered the Fleet to prepare to sail at 7 pm that evening and the aircraft-carrier HMS Formidable to embark torpedo-carrying aircraft. He then said: ‘I am going ashore for a game of golf,’ and I went with him. After the game, making sure that the local spy, the Japanese consul, was in earshot, the Admiral discussed with me the details of a mythical dinner party ashore that evening, put the empty suitcases in the car and went to have a cup of tea with Lady Cunningham at the Residency, which he had been lent to live in. At 6.30 pm as darkness fell the Admiral and I returned to HMS Warspite and the Fleet sailed at 7 pm.

  As soon as Cunningham had received the first X-3 message, on 25 March, giving notification of 28 March as D-day for the Italian operation, he cancelled the Royal Navy convoy from Piraeus and instructed the Alexandria convoy to continue northwards as planned, but to turn round at dusk on 27 March, so as not to arouse suspicions. He then ordered his ‘B Force’, based at Piraeus under Vice-Admiral Henry Pridham-Wippell, and the ‘C Force’ at Alexandria to the points where the convoys would have been at dawn as calculated by the Italians, and thereby ‘endeavour to make the enemy strike into thin air whilst taking all action possible while he is doing so’. It was only shortly after midday on 27 March, when he received the ULTRA message on X-1 giving the first intimation that there was a possibility of a naval engagement rather than just protection of the convoys, that he signalled to the Admiralty: ‘I have now decided to take 1st BS [first battleship, i.e. HMS Warspite] and HMS Formidable to sea after dark tonight.’ Cunningham was duly carrying out all the instructions that Wing Commander Winterbotham had laid down for a commander receiving an ULTRA message: never refer to the secret source which promoted the action but make it sound like his own impromptu decision and make sure that a cover-up was in place, in Cunningham’s case aerial reconnaissance. Doubtless the Special Liaison Unit officer who delivered the ULTRA message would have, according to the instructions, destroyed it after perusal. Fortunately, in early March 1941, a special signals link had been set up between the SIS communications base at Whaddon and Alexandria to pass the Bletchley intelligence on to senior British commanders in Egypt.

  Dilly’s girls knew that he was delighted about what he called the ‘cottage aeroplane’, but not knowing the ULTRA deception, they thought it related to the official story of reconnaissance in all the newspapers, when an airman got a much-publicised award for spotting the Italians. In fact, when I was asked to do the entry on Dilly for the Dictionary of National Biography’s Missing Persons volume in 1992, I still thought the cover-up was for the deliberately misleading press release. The official history in 1979 had hardly been informative about Cunningham’s plan and it is only revealed as an afterthought, in a footnote which says that ‘the conclusion that he decided to sail only after receiving the aircraft sighting at 12.30 on 27 March is incorrect’. Italian records on what they called Operation Gaudo indicate that Admiral Angelo Iachino had a cryptographer on board who broke the signal, as Cunningham knew they might well do, but the RAF Sunderland from Malta gave pre-arranged false information, so from our point of view no harm was done. However, it now appears that, throughout the night battle, the Italians continued to intercept many of the signals passed between Cunningham and Pridham-Wippell, which must have caused Cunningham problems. At this stage of course there could be no help from ULTRA; our advance intelligence could only influence strategy, tactics were lonely on-the-spot decisions for the admiral and by all accounts the night action was brilliant. On the night of 28 March, the Royal Navy crushed its Italian counterpart with three British battleships sinking an entire Italian cruiser squadron of three heavy cruisers and two destroyers, with the loss of 3,000 Italian sailors. The Italians had no radar so the British caught them completely by surprise. The Italian navy never challenged the Royal Navy in the Mediterranean again.

  It was in the early hours of 29 March that ‘Nobby’ Clarke’s son Edward received the news of the victory in the Bletchley Park naval hut from Admiral Godfrey. By the following day Dilly was ready with a poem called ‘Swollen Heads’ to celebrate the occasion, naming every one of his Cottage girls who had taken part, including the tea lady, who had been brought in so that we should not have to waste time wrestling with a cantankerous urn; so Mrs Balance, the tea lady, who was the mother of one of the Cottage girls, had duly signed the Official Secrets Act. Each verse began with the words ‘When Cunningham won at Matapan by the grace of God and…’, taking it in turns to mention each girl with a rhyming tribute; the rhyme for Mavis conveniently being rara avis. All very flattering for a nineteen-year-old. Dilly was considered by some to see cryptography only as a theoretical problem unrelated to real events; but that was a mistake. Undoubtedly aerial reconnaissance played an important part in allowing Cunningham to draw up his battle plan, but it was Dilly who rang the Admiralty immediately to make sure that when the battle was reported in the press its success would be attributed entirely to air reconnaissance to cover the real source. He chuckled in his poem when he referred to the reconnaissance ‘Cottage aeroplane’.

  When Cunningham won at Matapan

  By the grace of God and Claire,

  For she pilots well the aeroplane

  That spotted their fleet from the air.

  When Cunningham won at Matapan

  By the grace of God and Jane,

  For she was the girl who spotted the Wops

  From the Cottage aeroplane.

  When Cunningham won at Matapan

  By the grace of God and Nancy,

  Now she is a girl, the Admiral said,

  That might take anyone’s fancy.

  When Cunningham won at Matapan

  By the grace of God and Mavis,

  Nigro simillima cygno est, praise Heaven,

  A very rara avis.

  When Cunningham won at Matapan

  By the grace of God and Margaret,

  It was thanks to that girl, the Admiral said,

  That our aeroplanes straddled their target.

  When Cunningham won at Matapan

  By the grace of God and Phyllida,

  And made that impossibly self-willed girl

  If possible self-willeder.

  When Cunningham won at Matapan

  By the grace of God and Hilda,

  And sank the Vittorio Veneto

  Or at least they can’t rebuild her.

  When Cunningham won at Matapan

  By the grace of God and Jean,

  And if Jean Harvie had been there too,

  Hoots man, what might na ha been?

  When Cunningham won at Matapan

  By the grace of God and Mrs Balance,

  Indeed, he said, the Cottage team

  Is a team of all the talents.

  When Cunningham won at Matapan

  By the grace of God and Elisabeth,

  The credit was almost entirely ours

  But possibly God did his a bit.

  Dilly then added a tribute to the two people who had made the ULTRA treatment possible, ‘Nobby’ Clarke and Admiral Godfrey, the DNI.

  When Cunningham won at Matapan

  By the grace of Godfrey and Nobby,

  Though not of our outer or inner rooms

  They’re allowed sometimes in the lobby.

  Clarke added his own, much to the point, verse later:

  When Cunningham won at Matapan

  By the grace of God and Dilly,

  He was the brains behind them all

  And should ne’er be forgotten. Will he?

  When we suddenly heard later that Cunningham was coming down with Godfrey to congratulate us in person, we rushed down to the Eight Bells at the end of the road to get some bottles of wine and if it was not up to the standard the Commander-in-Chief Mediterranean was used to he didn’t show it. The Cottage wall had just been whitewashed. Someone enticed the admiral to lean a
gainst it and we tried not to giggle when he left. He had shaken us all warmly by the hand and we thought that was the end of Matapan. It was in fact practically the last we would hear of the Italian fleet, which only made one more appearance before surrendering to Cunningham in 1943.

  For Dilly’s girls, as for the rest of Bletchley Park, we were Churchill’s ‘geese who laid the golden eggs and never cackled’. Most of us were grandmothers by the time Frederick Winterbotham’s book The ULTRA Secret appeared in 1974, with an illustration of Bletchley Park on the cover; we were horrified. Could we now tell our families why we were so good at anagrams and Scrabble and crossword puzzles then? We eagerly looked in the index for Dilly Knox and thoroughly approved that it said he was ‘the mastermind behind the Enigma affair’; but there was not a mention of the Cottage and Matapan was wrongly credited to the Luftwaffe break in Hut 6 since Winterbotham only knew about the German air force ULTRA intelligence and nothing about the Italian. What about the rods and X-3 and the drink with Cunningham and Dilly’s poem? Maybe Dilly’s mentor Lewis Carroll was right after all and life was but a dream.