Most Secret War

by R. V. Jones

  We may expect many months’ life for 10 cms. A.S.V., providing that we do not give the Germans a clue to the wavelength. The capture of H2S will not only do this, but also show them a satisfactory receiver design. Moreover, having captured H2S, they may have some difficulty in producing transmitters to jam it (should they not resort to spoof reflecting devices), but this difficulty would not exist with A.S.V., for the only necessary counter is a receiver.

  The fact is obvious that should we try H2S first, and should it prove relatively unsuccessful, 10 cms. A.S.V. will have a spoilt chance, and we shall have lost everything. Should we, however, reverse the order, we could test whether or not 10 cms. A.S.V. is an important factor in countering the mortal threat of the U-Boats, and still be in a position to use H2S later, should we choose. The latter finessing course therefore appears correct, unless there is some overwhelming operational factor in favour of a precipitate use of H2S, or of any other application of 10 cms. which is likely to fall into the hands of the enemy.

  My intervention convinced Medhurst, who raised the matter on an inter-Service basis in a last effort to get the priorities changed; but he came back to tell me that the Services could do nothing to overcome Cherwell’s enthusiasm for H2S going into Bomber Command first. Coastal Command now had to face the high probability that the Germans would recover the equipment from crashed bombers and realize that we were likely also to use it against U-boats, for which the only countermeasures needed would be to equip the boats with suitable receivers. The Naval Intelligence Division therefore requested that, as with Gee, I should attempt to mislead the Germans about how we were now finding the U-boats. There was an additional urgency to this request because we had another way of finding U-boats which was even more important that H2S, at least as regards their general location. This was the German Naval Enigma signals, which by a further feat Bletchley had managed to decipher. The Naval Enigma machine was more complex than that used by the Luftwaffe in that it included a fourth wheel, thus multiplying the number of combinations which had to be unravelled.

  The basis of the deception was that we should give the impression that we were finding the U-boats not by radar, or by their Engima signals, but by infra-red. I therefore provided a series of clues, aided once again by ‘George’, and this appears to have been successful; for not only were the Germans very slow in realizing that we were using centimetric radar against them at sea, long after they had found it in our crashed bombers, but they also developed a most ingenious paint for their U-boats to camouflage them against infra-red as well as against visible light. If a normal grey-painted ship, which is thus camouflaged well against a typically grey sea, is viewed by infra-red it still looks grey but the sea looks blackish. They therefore had to make a paint which looked grey to the human eye, but blackish to an infra-red viewer. They achieved this by putting a black undercoat on the U-boats, and covering it by a varnish which contained a suspension of powdered glass in sufficient quantities to give a grey effect when viewed by the human eye. The glass and varnish were, however, so chosen that their refractive indices were identical in the infra-red, which went through the mixture and was absorbed in the black undercoat. It was a clever idea, and I much admired the German physicist who thought of it.

  The new centimetric A.S.V. set was first used in the Bay of Biscay on 1st March 1943, and it was not until the following September that the U-boats began to dive on its approach, suggesting that they were at last equipped with centimetric receivers to give them advance warning. The six months uncountered use of centimetre A.S.V. was much longer than we had dared to hope, especially since the Germans must have found virtually the same equipment in our bombers. Writing of this episode in their book Methods of Operational Research published in 1951, Professor P. M. Morse of the Massachusetts Institute of Technology and Professor G. E. Kimball of Columbia University said, ‘How this six months’ delay occurred is one of the mysteries of the war (it can perhaps be explained only by a criminal lack of liaison between the German naval and air technical staffs).’ An alternative explanation may lie in the infra-red hoax.

  And another hoax may also have played a part. A British prisoner of war under interrogation ingeniously told the Germans that our aircraft were homing on to some kind of radiation that was coming out of the ‘Metox’ receivers which were used by the U-Boats to detect the approach of our original A.S.V.-equipped aircraft. It was a complete fabrication, but when the Germans investigated they found that there was indeed radiation coming out of the Metox receiver, and they went to some trouble to suppress it—without, of course, any success in reducing their U-Boat losses.

  When the Germans finally realized that we were using radar after all, they fortunately blamed it for all their U-boat sinkings, Dönitz even going so far as to say that this one invention had changed the balance in the battle of the Atlantic, and our Enigma feat remained secure.

  With all these side-efforts, in addition to our main activity, I was increasingly concerned that we should miss something vital. Altogether there were only five of us, and between us we closely read a daily input of about 150 sheets of foolscap paper, besides attending meetings, visiting R.A.F. stations, and so forth. I therefore submitted a paper to Frank Inglis, who had now succeeded Charles Medhurst as Assistant Chief of Air Staff (Intelligence), on 20th November 1942 pointing out that without a substantial increase in staff

  there is an extreme danger that something vital will be missed. In view of Hitler’s recent statement that German inventive genius had not been idle in developing new weapons of offence against this country, we cannot afford to relax our watch as we have been forced to do … unless some relief is forthcoming, the present Assistant Directorate cannot accept responsibility for the surprises which are likely to be sprung upon us by the enemy without the timely warning which has been achieved in the past.

  Four weeks after this warning, there arrived in my office a telegram from Stockholm dated 19th December 1942 saying that a new source ‘overheard conversation between Professor Fauner of Berlin Technische Hochschule and engineers Stefan Szenassi on a new German weapon. Weapon is a rocket containing five tons explosive with a maximum range of 200 kilometres with a danger area of 10 kilometres square.’ In answer to my enquiry, the reply came that the source was a Danish chemical engineer. His report was followed by another from Sweden dated 12th January 1943 saying that, ‘The Germans have constructed a new factory at Peenemünde, near Borfhoft where new weapons are manufactured.… The new weapon is in the form of a rocket which has been seen fired from the testing ground’. Although the authenticity of this second report could be in doubt (for it went on ‘It was previously tested somewhere in South America’), these two rocket reports, at that time no more than ‘a little cloud out of the sea, like a man’s hand’ in fact foretold a deluge; but in the meantime there were further points in my memorandum to Inglis.

  Before Medhurst had left Intelligence, he had advised me to expand my staff in my own interest, since status tended to depend on the number of men directly responsible to the holder of a particular post. I told him that I would prefer to define responsibility as the scope for ‘dropping bricks’, and that my basic difficulty was that the expansion of Scientific Intelligence had started much too late. Since I was not allowed to recruit anyone until after more than a year of war, all the ablest people had been fitted into posts, and it was now difficult to prise them out.

  I now had to look for men whose qualities and background were not those of a normal scientist. Hugh Smith was such an example. At the same time, as my memorandum to Inglis had stressed, there was much to be said for using as few individuals as possible, and stretching them to their utmost.

  It has been part of our policy to keep the staff to its smallest possible limits consistent with safety, because the larger the field any one man can cover, the more chance there is of those fortunate correlations which only occur when one brain and one memory can connect two or more remotely gathered facts. Moreover, a large
staff generally requires so much administration that its head has little chance of real work himself, and he cannot therefore speak with that certainty which arises only from intimate contact with the facts.

  It was an encouraging experience to find just how much a few individuals can do, and how even a single individual can sometimes be more effective than a large organization. During the Battle of the Beams in 1940 and 1941, I myself read every Enigma message. A full record of such messages came to me daily from Bletchley, and in the early days they were typed on different typewriters, or sometimes the same typewriter with different ribbons or different carbons. I could usually remember the date on which a message had been received, the colour of the carbon copy, and its degree of blurring, along with the part of the page on which the message had been typed. It was therefore usually a matter of seconds for me to flip through the file and pick out a particular message, even two months later. After I had done this a number of times over the telephone in discussions with Norman he had said enthusiastically, ‘You must have a marvellous filing system! We have an enormous one here, and yet we can never find a message as fast as you can. Can we come up and see your system some time?’ I told him that I should be delighted to show him and his colleagues, but it was hardly worth their making a special trip.

  Norman’s honest surprise when he found that the index was in my head was one thing; but the suspicions of others were less easy to deal with. The information must have been churning continuously around in my head, only returning to the conscious when some hitherto unseen correlation presented itself. The effect of producing these correlations out of the head, if not out of the hat, was to lead some of our associates to think that I had a great source of information that I never revealed to anybody outside.

  There were at least three attempts made to infiltrate liaison officers into my Section to locate this great undisclosed source. In one, an officer from Bletchley was offered to me on a part-time basis to help but, as he told Norman and me afterwards, his main task was to uncover my mysterious source. After a month or so, he was called back and asked what he had found. He assured his seniors at Bletchley that there was no trace of anything other than what they already knew. When someone asked, ‘Then how does Jones do it?’ Bob Pryor, the officer concerned replied, ‘Well, I suppose, Sir, he thinks!’ Another officer who had been infiltrated became so enthusiastic as to have defended me to an Air Commodore who told him that I was a funny chap, and that he, the Air Commodore, had not been able to get on with me. ‘Well Sir,’ was the reply—and it came from a Flight Lieutenant—‘You must remember, he doesn’t suffer fools gladly!’

  Be that as it may, we were all under strain. I had rowed at Oxford just under 175 lbs, which had increased to about 195 lbs by 1939. By the end of the war I was down to 170 lbs. I had no easements such as a staff car, and my civilian rations were substantially lower than those of the serving officers who worked under me. At the same time the strain was much greater on our wives, particularly one such as Vera, who was now bringing up a family in London, and who could not have the absorbing interest in the war that kept me going. Perhaps because she looked after herself last, she became so run-down that she suffered from a most painful series of abscesses.

  Only once did my own interest divert from the immediate war. Irrelevant though it may seem, the issue deserves to be recounted at length, because it contains an element of eternal truth concerning the mentality of those who select themselves as planners. It was in January 1943, the period of this chapter, and of the optimism engendered by our recent successes in North Africa, when I read of the post-war plans for education in physics that had been put forward by a committee of the Institute of Physics. The plans, such as they were, prompted me to write to the Secretary of the Institute on 3rd February as follows:

  Every time that the fortunes of war turn in our favour, up springs a crop of post-war planners. The recent sustained absence of bad news has swelled the latest crop to large proportions, and it is a matter of surprise that so many scientists—of whom we are so short—have so much time to spare at this period of the war. While at first sight it may appear wise to plan ahead, it is open to question whether we are beginning in the best way.… By 1935 at the latest, it was obvious to any man of foresight that there was a high chance that this country would shortly be involved in war. Those who realized the danger, and who had sufficient patriotism, abandoned their comfortable academic lives and accepted the more rigid discipline of Government service—not that they always approved of its machinery—in an effort to parry the military developments of science in Germany. Those with less foresight stood outside and often criticized destructively the efforts of Dr. Blimp. Those with less patriotism talked of the freedom of science and clung to their academic existences. The majority was merely apathetic and comforted itself with the delusion that Nazi Germany without Semitic inspiration was scientifically sterile. When war did break out, and foresight and public spirit were hardly required, most of the academic scientists of course flooded in, but they were mainly too late to have helped materially at the great crisis of 1940. Those scientists with foresight and public spirit therefore joined some form of Government service in the years before the war, and are likely to have been given responsible positions which require the devotion of all their energies to winning the war. Thus, those with the qualities necessary for planning are identically those most likely to be at present, and to have been for years past, completely absorbed in the war. Our best potential planners are therefore not available… the decision regarding the timely release of planners is surely beyond any body consisting purely of scientists. The best initial planning step that scientists could take would be to present this view to those concerned with the highest direction of the war, and in the meantime to ensure that no effort which could successfully shorten the war is wasted in premature planning.

  My doubts were justified: the report of the Institute of Physics Committee was not all that bad, but it was so phrased as to be misread, at least in Scotland, to the extent that the Committee on Secondary Education in Scotland (which met shortly afterwards), thought that the physicists had recommended that physics and chemistry should have an even lower priority in education than they previously had, and should be replaced by general science. It took me five years after the war to rectify the damage that had thereby been done. And many subsequent events have reinforced my doubts about the presumption of those who would be planners, not only in education but in the long list of grandiose government and civil projects that have led to disaster, ranging from the Ground Nuts Scheme to the Robbins Committee.

  In contrast with the remoteness of post-war planning, my needs for more staff were immediate; and finally it was agreed that I should have an increase. John Jennings joined me towards the end of 1942: he was a physicist whom I had met in pre-war days when he had been taken on by the Philips Organization to liaise between the Admiralty and the Philips works at Eindhoven. Besides his physics, he had a knowledge of German, French, Spanish, Dutch, and Russian, and thus proved a valuable reinforcement. At about the same time Squadron Leader J. A. Birtwistle joined us. He had a science degree and had been an Intelligence Officer with Fighter Command, particularly at Kenley during the Battle of Britain. One of the first questions I asked him was about our overclaiming during the Battle, and why Intelligence Officers had let so many doubtful claims stand. As he put it to me, he was in the position of having to deal with pilots in an understandably excited state on coming out of an air battle, and it was quite impossible for an officer who had not been risking his neck as they had to say that he was not going to allow their claims.

  One further reinforcement, who arrived on 1st April 1943, was E. M. Wright, who was then Professor of Mathematics at Aberdeen. I had first met him in 1932, when he was building an outstanding reputation as a pure mathematician in Oxford. He had been appointed to the Chair at Aberdeen in 1935, when he was still 29, despite having come up to Oxford late, and we used to meet on his per
iodical returns to Oxford. When I found, towards the end of 1942, that he was not directly involved in the war, I wrote asking whether he would care to join me. He readily agreed, and he had been with me little more than a month when Jack Easton, one of the Directors of Air Intelligence telephoned me on the morning of Monday 10th May to say that a Junkers 88 nightfighter had landed at Dyce, and suggested that I should go up there to take charge of it. Previously all that Dyce had meant to me was a monosyllabic aerodrome, like Drem and Wick, in Scotland. ‘Isn’t Dyce somewhere near you?’ I asked Wright, and when he said that it was his local aerodrome, I offered him a trip to accompany me to Aberdeen. We travelled on the night sleeper, and went out on the Tuesday morning to look at the aircraft.

  It was intact, and fitted with the Lichtenstein radar equipment (Plate 18) that only a few months before we had been at such pains to elucidate. Its crew of three told us that they had had little sympathy with the Nazis, and that when they had received orders to shoot down our civil courier flying between Scotland and Stockholm, it was time for them to get out of the war. So, during a normal sortie they signalled that they had an engine failure (or fire) and were losing height: in fact they dived down to sea level to get below the German radar cover, and then headed for Aberdeen. They were detected by our radar, and intercepted by two Spitfires from a Canadian squadron who recognized that their intentions were not offensive, and who took the risk of escorting them over Aberdeen and into Dyce. At the airfield, the ground defences opened fire, but fortunately missed, and the Junkers landed safely. I much admired the restraint of the Canadian pilots, because I knew of several instances where fighter pilots had shot down our own returning aircraft; and even though the German crew were waving white handkerchiefs, many fighter pilots would have opened fire. One of my more diverting efforts on returning to London was to try to get the two Canadians awarded the Distinguished Flying Cross for not shooting the Germans aircraft down. This was rather too much for the Air Staff, but they did finally agree that the pilots should be Mentioned in Despatches.