Chapter 8


"And there is something else interesting: Erwin K. Oppenheimer maintained that the bomb that was dropped on Japan was of German provenance. "

Edgar Mayer and Thomas Mehner

Das Geheimnis der deutschen Atombombe 1

1 Edgar Mayer and Thomas Mehner, Das Geheimnis der deutschen Atombombe: Gewann Hitlers Wissenschaftler den nuklearen Wettlauf doch? Die Geheimprojekte bei Innsbruck, im Raum Jonastal bei Arnstadt und in Prague, p. 122.

One of the most problematical documents to explain from the standpoint of the postwar Allied Legend is the top secret memorandum concerning the development of an atom bomb anonymously submitted to the German Army Ordnance Bureau (Heereswaffenamt) in early 1942. This document not only correctly estimated the critical mass for a uranium-235 based bomb, but also indicated the possibility of transmutation of uranium into plutonium - called "Element 94" by the memorandum - and its use in a bomb.

The memorandum's origin and authorship has been attributed to various interred Farm hall scientists, including Dr. Kurt Diebner. But the authorship is unknown, and the problem of its existence remains: How could the German army, knowing that the required amount of uranium for a nuclear bomb was comparatively small and therefore technically feasible, not have pursued its development? And how could they have pursued such laughably pathetic attempts toward a functioning reactor? The mystery only deepens when we consider a possible ancestry for the Heereswaffenamt memo written in a paper the previous year.

In 1941, Baron Manfred Von Ardenne decided to circulate an unusual paper by his colleague Dr. Fritz Houtermans. The full title of the paper was "On the Question of the Release of Nuclear chain reactions, by Fritz G. Houtermans: A Communication from the Laboratory of Manfred Von Ardenne, Berlin-Lichterfelde-Ost."2

The paper is remarkable in several respects, not the least for its revealing table of contents:

I.   General Point of View

II.  Competing Processes

III. Chain Reactions through Nuclear Fission with Fast Neutrons


Nuclear Fission through Thermal Neutrons
  1. Isotope Separation

  2. Selection of a heavy Moderator Substance such as Hydrogen, especially Heavy Water

  3. Relative Advance of the Probability for 1/v Process through Application of Low Temperatures

  4. Self-Regulating reaction and the Significance of the Doppler Effect at Low Temperatures

V. Chain Reactions at Final Trial Volumes

VI. The Importance of a Chain Reaction at Low Temperatures as a Neutron Source as an Apparatus for Isotope Transformation 3

2 Thomas Powers, Heisenberg's War, p. 112. The table of contents page of the original memorandum may be found in Mayer and Mehner, Das Geheimnis, p. 33.

3 Ibid., p. 32.

The general outline suggests that Houtermans had already thought his way through the process, not only of initiating nuclear explosions via fast neutrons, but also of the transformation of U235 into higher elements not chemical identifiable with it. This is the first step toward plutonium, and to the use of plutonium rather than U235 as the explosive fuel for a bomb. The contents of the paper confirms that this is what Houtermans has figured out in no uncertain terms:

We are able to envision here an apparatus, that would allow...a certain amount of U235 to undergo nuclear reaction, simultaneously as an isotope transforming apparatus. The advantage vis-a-vis an isotope enrichment apparatus is therefore that the newly-created product, which would have an atomic number of 93 or more, is not chemically identical with uranium, and therefore is separable by chemical methods. Now since much larger amounts, namely 139 times more, of U238 are available, so the amount that would be convertible as fuel for a chain reaction is, from the standpoint of our theme, much more important than isotope separation that would result in mere U235.4

4 Mayer and Mehner, Das Geheimnis, p. 32.

In other words, before the 1942 Heereswaffenamt memo (which not only gave a critical mass of a bomb with U235 as the explosive fuel that is within the range of accuracy, but which also indicates the transformation of uranium into plutonium in a reactor as an alternative fuel returning more bang for the Reichsmark) Houtermans has clearly seen another path to the atom bomb. He may therefore also be considered a leading candidate, if not the leading candidate, for the authorship of the anonymous Heereswaffenamt memorandum. His Jewish background would explain why the memorandum was authored anonymously.

So, having speculated in previous pages that Nazi Germany had actually pursued a uranium bomb as the primary component of its bomb, and conducted a large and very secret uranium enrichment project in order to acquire it, we now come to the subject of the possibility of a plutonium bomb project, conducted once again in secret, and far from the "public exposure" laboratory tinkering of the Farm Hall scientists. In this respect there has already been one indication: the allegation of a second nuclear test of a bomb with a very small critical mass via the process of boosted fission, near the Three Corners region of Thuringia, an area that has the highest gamma background radiation in all of Germany.

Are there corroborating indications that the Germans might have successfully developed an atomic reactor, and hence, plutonium, in the secret recesses of Kammler's SS black programs secret weapons empire? Henry Picker, in his book Hitler's Table Talk, makes one significant statement. Not only does he indicate that the Reichspost had something to do with the atom bomb project, but he offers more detail. The bomb was to be constructed in a plant "in an underground SS factory in the southern Harz mountains, which had a foreseen production capacity of 30,000 workers."5

Once again, the trail leads back to the SS, the southern Harz mountains of Thuringia, and large underground factories. This facility, according to Picker, "was transferred back to the USSR by the Red Army" after the German surrender.6 According to Picker, it was for this reason that Stalin reacted with such detachment when President Truman informed him of the successful test of the plutonium bomb at the Trinity site in New Mexico, for Stalin had already acquired the necessary technology to make his own atom bomb. Moreover, Stalin awarded Manfred Von Ardenne the "Soviet 'Nobel Prize,' the Stalin Prize."7

Mayer and Mehner comment on the real significance of this series of admissions:

Everything clear? The Russians thus came into possession of some means of production - which from then until now remains unknown -and paid off Manfred Von Ardenne, who was certainly the best consultant in these things, who must have clarified for them the things the Russians had found there.8

It is an intriguing idea, for we have already discovered a possible plutonium bomb detonation near Ohrdruf very late in the war.9 This would of necessity imply that the Germans had acquired a successful atomic reactor, the question is, where? In any case, the reason for lack of knowledge about this project is clear: it was in the control of the SS, and therefore, within the portfolio of the security-obsessed General Kammler.

5 Henry Picker, Hitler's Tischgesprachen im Fuhrerhauptquartier, 2 Auflage (Berlin: Propylaen taschenbuch bei Ullstein, 1997), cited in Mayer and Mehner, Das Geheimnis, p. 34.

6 Ibid.

7 Mayer and Mehner, Das Geheimnis, p. 34, citing Picker.

8 ibid.

9 Uranium could of course have been used in a boosted fission device, butthe process works better with plutonium, and plutonium would more likely account for such a small critical mass as was reported, namely, 100 grams, since more than that would have been necessary for a uranium bomb even with boosted fission.

In any case, Houtermans' reactor concept was significantly different than Heisenberg's, or for that matter, even Enrico Fermi's successful atomic pile at the University of Chicago, since it aimed at the production not of energy, but of radioactive isotopes. For this reason, it would be able to operate at low temperature using liquid methane as a moderator, rather than heavy water or graphite. This meant that it would be an efficient producer of "element 93 or higher" that could be chemically separated and used as a nuclear explosive.10

This is significant, for it differentiates the Von Ardenne-Houtermans effort both from the Heisenberg effort to design and construct a working atomic pile, and from Enrico Fermi's success in doing so.11

10 Rose, op. cit, p. 141.

11 Researcher Frank Joseph has found another source for a reactor, and consider his information to be so crucial to this story, and so sensational, that cannot in good conscience mention it in this work. I believe that it is a story that he best tells himself, since it is his discovery. He was kind enough to share it with me as this book was being written.

So at one end of the war, ca. 1945, we find the allegations on tested weapon of small critical mass which, if true, is most liked that of a plutonium bomb using a process of boosted fission, and at the other end, ca. 1941, we have a paper outlining a project to achieve a reactor for the production of the explosive fuel of such a bomb. There is an odd piece of corroboration that the Germans may also have been perilously close to, if not in actual possession of, a plutonium atom bomb, from the Pacific Theater and the Japanese program.

Robert Wilcox, in his Japan's Secret War, recounts how the Spanish Nationalist government successfully ran a spy ring both for the Germans and for the Japanese, an espionage operation that had no little success in penetrating the Manhattan Project, even to the extent of acquiring in 1943 the earliest Allied designs for a detonator for such a bomb. Interviewing Angel Alcazar de Velasco, the alleged head of the ring, Wilcox quotes a rather astonishing statement:

The information was that the American work on a nuclear weapon was very advanced but they had a long way to go. There were even notes about the detonator. It was similar to one already in use by the Germans. 12

A complicated detonator - presumably for use in a plutonium bomb, since the detonator mechanism for a uranium bomb is a much simpler piece of equipment - already in use by the Germans in 1943!? Why would the Germans have had the need for such a complex detonator? The timing of the allegation is also disturbing, since it corroborates the assertions, examined earlier, of the Japanese military attaché in Stockholm, that the Germans were using some type of weapon of mass destruction on the Eastern Front ca. 1943, in the region of Kursk.13 But Houtermans was interested in more than just atom bombs.

Even Paul Lawrence Rose admits that Houtermans' role in Nazi atom bomb research "remains enigmatic."14 The reason why, though, is clear enough, once its enormous implications are understood, for Houtermans' real specialty lay in the first theoretical description of the process of thermonuclear fusion of heavy hydrogen (deuterium and tritium) atoms through high heat in stars, the very heat produced by an uncontrolled chain reaction.15

12 Wilcox, op. cit, p. 28, emphasis added.

13 The attache, it will be recalled, actually maintained that these weapons - whatever they were - were also used in the "Crimea", making it most likely during the siege of the Russian fortress of Sevastopol in 1942. Thus would seem to weigh very heavily against this mystery weapon being an atom bomb. But if not, what other weapon could have caused such destruction? This is a question that will be more fully addressed in subsequent parts of this book. Powers notes that Allen Dulles in Zurich received reports of a German project in "vast underground factories" that were after "putting out a new explosive in aerial bombs. He has even heard that the container of the explosive is spherical." (Rose, op. cit., p. 272, emphasis added) A spherical detonator, of course, is the type of implosion-compression detonator used to assemble the critical mass of a plutonium bomb.

14 Rose, op. cit., p. 51, n. 38.

15 Q.v. Powers, Heisenberg's War.

With this, we are a step closer to unlocking the riddle of just exactly what types of weapons Kammler's "think tank" was working on, for if Hotelmans' idea was seized upon, then hydrogen bombs would have been the next logical progression in the "technology tree" from the atom bomb, just as it was for the Americans and Russians after the war. Is there any indication the this was in fact the real ultimate goal of the secret German SS atom bomb program? In other words, was it really an atom bomb program at all? Or was it a hydrogen bomb program?

Fantastic as it may be to believe, the latter possibility would seem to be the actual case. The letter of Professor Lachner referred to previously also gives further illumination on the goal of Kammler's SS Sonderkommando:

Work was also conducted on the hydrogen bomb. A factory for the manufacture of heavy hydrogen was constructed in Norway but was of course destroyed by the enemy. The small uranium bombs were primarily intended as detonators for the hydrogen bombs, so their immediate use was not contemplated.16

Another corroboration for this astonishing assertion may be found in a pre-war Austrian patent for a "molecular bomb", an early version of the hydrogen bomb, from 1938.17 In any case, Professor Lachner asserts unequivocally that the real goal of the project was weapon more terrifying and destructive than the atom bomb.

Another factor is worth mentioning in this regard. The pursuit of the hydrogen bomb would also explain why the Nazis were interested in small atom bombs, made smaller via boosted fission, for a hydrogen bomb, at least with the technology available back then, would have been an enormously heavy and cumbersome object. The quest for "miniaturization" was therefore another practical aim: any such bomb would have to be made small enough for German bombers or rockets to carry, and even then, only the very largest bombers or rockets would have been up to the task, if at all.18

16 Mayer and Mehner, Das Geheimnis, p. 80.

17 Ibid., pp. 255-256.

18 It should be recalled that the first hydrogen bomb, America's "Mike", weighed several tons, and was impractical as an actual weapon. America's first operational hydrogen bomb actually weighed several tons. It is difficult to imagine any existing aircraft in the German arsenal, not even the enormous Ju 390, as being up to the task of delivering a hydrogen bomb, and the specifications for the A9/10 Amerikaraket are far below what would be needed bomb, it (or they) were seldom if ever actually used, being husbanded as detonators for something far more powerful? Does this also explain, in part, the real reason for the curtain of secrecy that fell over Kammler's special SS "think tank" command structure?

But to produce hydrogen bombs, one must have an adequate supply of the heavy hydrogen isotopes deuterium and tritium. Here again, however, the Allied Legend intervenes, and maintains that after the successful Allied destruction of the Norwegian heavy water plant at Ryukon, German production of the precious destructive substance was never able to recover, and, as a consequence, heavy water for a moderator in reactors (much less a hydrogen bomb!) was never in enough supply.

The further implication of this assertion is, of course, that the failure of Heisenberg and other scientists to construct a reactor based on heavy water as a moderator was doomed to failure because of the lack of supply. But again, the reality was quite different. Dr. Diebner in an exchange with Dr. Wirtz - both later interred at Farm Hall -indicated that a complete heavy water plant was built in Germany by the end of 1943.19 However, revelations made at the end of the war were even more important as a means of measuring the truly significant extent of German heavy water production: a large heavy water factory, hitherto entirely unknown, had been discovered by the Allies in Kiel in northern Germany.

But most importantly, after the German reunification in 1989, when the vast SS underground factories in the Harz region of Thuringia in the former eastern zone were rediscovered, many of these were found to contain several large electrical generators, enough to supply power for a few small cities! 20

Such high electrical output would certainly not have been needed for the last Fuhrer Headquarters, but it certainly would have been required for factories separating uranium isotope (especially if they used Von Ardenne's cyclotron process), and that manufactured heavy water. Was the hydrogen bomb the real goal? Does this explain the reason that, if Germany did have the atom for such a bomb. The only practical method of delivering a hydrogen bomb, it seems to me, would have been via a large submarine or ship to a port city, a militarily quite risky venture, and one that, for the German crews involved, would have been a one way venture.

19 Mayer and Mehner, Das Geheimnis, p. 197.

20 Ibid., p. 198.

One indication that this may be so were remarks made by Dr. Josef Gobbels to the Italian officer Luigi Romersa who witnessed the Rugen atom bomb test, whom we encountered earlier. According to Romersa, Gobbels told him,

"Heavy water is an important material in the manufacture of the disintegration bomb.21 We had already before the war made some headway in the direction..."22

Headway indeed, if an Austrian patent for prototype had already been taken out in 1938!23

21 Auflosungsbombe.

22 Mayer and Mehner, Das Geheimnis, p. 102.

23 Such a patent would have been immediately classified as a "Geheime Reichsache" or "secret state matter", i.e., a matter of national security as would now be said. As such, it would have definitely made its way directly to Kammler's "think tank," as will be seen in subsequent parts of this book.

That the ultimate goal of the German atom bomb project was the hydrogen bomb, and not the atom bomb at all, seems in retrospect both quite logical and quite disconcerting. As we shall discover in the remaining parts of this book, however, even hydrogen bombs pale by comparison not only just to the "paper projects" being studied in Kammler's SS Sonderkommando, but to the very real projects and experiments with forces of even larger potential destructive capability than hydrogen bombs. Having foreseen the thermonuclear future, the SS was already planning and experimenting with countermeasures, and with second and third generations of offensive strategic weapons even more horrifying.

The Allied Discovery of a Heavy Water Plant in Kiel after the end of the War

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