Theories to explain lack of Prussian Blue (reply to patrick)

[Wetzelrad]

Apologies to anyone who is trying to read through this thread casually.

If I understand you correctly and please correct me if I’ve misunderstood you think the April 13 document is referring to the March heating device rather than to a second attempt I see several difficulties with that interpretation
First if that is the case the “2 Topf disinfestation ovens for Crematorium II in the prisoner of war camp, Auschwitz” would presumably have also been delivered and already supplied for almost a month

I wouldn't make that presumption. It's possible that all four projects on the list were delivered by that time, but it's also possible that deliveries were slow.

yet there is [no] mention of them in the documentary record or even an order for them?

I wouldn't make that assumption either. Beside the list on April 13, 1943, Mattogno raises two other documents that directly concern these ovens. On February 5, Topf sent its cost estimate for this disinfestation oven to the ZBL (The Real Case for Auschwitz, p.59). This was three days after the Kori firm had already sent its cost estimate and metal weight for a similar disinfestation oven (p.57). Another record is a July 28 invoice (for "Auschwitz-Krematorium" but likely referring to the Zentralsauna) which includes insulation work "for the disinfestation system" (pp.58,616).

Second Van Pelt states quite definitely in his affidavit that the equipment was delivered and installed in June obviously until we see the underlying document I don’t think we can simply treat his statement as independently demonstrated but he was giving evidence in a court affidavit so I think it deserves some weight

That Van Pelt's claim of June was put into a legal document should bestow it some weight, sure, except that Van Pelt states all kinds of things that are either not true or overzealous. For example, from the same affidavit: "The men in the Central Construction Office obviously realized that with the enormous daily incineration capacity at hand morgues had become unnecessary" (Source). He simply made this up based on what he thought was possible. Or: "Unlike crematoria 2 and 3, crematoria 4 and 5 were from the very beginning designed as killing installations" (Source). Many historians would deem this statement false, including Pressac, and also chief witness Rudolf Höss.

To me it is apparent that Van Pelt has seized on a single document that mentioned June and over-zealously claimed that that was the installation date. And this is similar, in my experience, to reckless claims that he and Pressac have made about documents generally. But by all means, let's wait and see if I am proven right.

I would also expect Irving or Rudolf if they believed Van Pelt was misrepresenting the chronology to address that specifically

I wouldn't because it's relatively minor. In my experience, the revisionists do not seize on every opportunity they could.

Third there seems to be an important technical distinction between the two systems the March device is described in connection with the forced draft system (aeration) the later device was connected to both aeration and deaeration the later device isn’t simply another description of exactly the same installation but more extensive arrangement and likely more powerful because it’s connected to both not just the 1

I don't agree. Both documents use the term "Warmluftzuführung", with the "zu" meaning supply only.

For the ventilation system generally, I translated "Be-und Entlüftungsanlage" as "supply and exhaust ventilation system", but I think that is an overly literal translation. The same term is usually translated to English as just "ventilation system", and I believe that is how it should be understood in this context.

Worth adding that Van Pelt does not share your opinion on there being two devices. You are out in novel territory.

I don’t think the fact that equipment was described as entwesungsofen settles the question of every intended application by itself equipment can be described according to its technical function without that description necessarily establishing every purpose for which it was ultimately intended to be slightly crude what do you expect the SS to order? “2 Zyklon heaters for the express purpose of gassing jews”?

Lol. Well, it's hard to know what to expect since this preheating scenario is not part of the regular story. If Topf and the ZBL were really considering repurposing these disinfestation ovens for homicidal gas chambers, I would expect some hint of evidence to appear in the documents or correspondence. There could for example be a letter noting how the Zyklon wasn't evaporating in a reasonable amount of time, hence the need for heat. Nothing like that exists. What actually exists for the disinfestation ovens is copious discussion of delousing efforts throughout the camp, in exactly these months.

“But does the overall chain of events make sense to you? Why did Topf get the idea to heat the gas chambers from the cremation ovens getting overheated? Shouldn’t they have already thought of that, it being the middle of winter?”
Well not particularly up to this point the SS had no issue gassing people without heat (bunkers and Krema 1) however it does raise a question for the revisionist why is it Topf that is suggesting this if heat is a requirement for a morgue backed by the expert literature? Would the ZBL not know this? So the pendulum swings both ways

But I think that is easily explain-able for the revisionist case. In the time that this device appears in documents, February-March, it was winter, but it was also just when KII was being brought online. The engineers did not yet know what the ambient temperature of the basements was going to be. They couldn't know this from Krema I because that was a completely different design. In support of this, a letter of January 29 noted that the ovens had only just been fired up for the first time, and construction in the basement was being held up by "frost". It actually makes a lot of sense that, in the first attempts to do cremation, the building was relatively cold and bodies held in LK1 were frozen, which led to the engineers contemplating warm air supply, only for that to be discarded as needless when more regularized operations warmed up the building.

Dragon could be describing an ad hoc temporary solution the SS came up with for Krema 2 in the 2 months from ordering the second device and it’s installation

He could also just be making it up, since it isn't corroborated by the many others who claimed to work there. According to his story, he was not in KII. He was in KIII in October and November 1944, so well after June 1943 and well after a permanent heating solution should have been figured out. And as Mattogno pointed out, burning coke indoors is a good way to gas yourself by carbon monoxide poisoning, so it's questionable why Zyklon would ever have been necessary with this option at hand.

On eye witnesses is true that we do not have an eyewitness who specifically says that there was a heating system installed inside the ventilation system of Krema 2 but there are eyewitness indications that LK1 was heated from some source that was not controlled by the sonderkammdo (like heaters)

Yeah, okay, but the strength of all this is abysmal. I can counter by pointing out how Ludwik Nagraba claimed cold water was sprayed on the Jews before gassing, in KII or KIII (Sonderkommando Auschwitz I, p.231). Shaul Chasan claimed the air supply in the KIII gas chambers was cold air (Sonderkommando Auschwitz III, p.67). This gets us back to a cold and damp environment.

At the same time Cohen gives some interesting information concerning Krema 3 where he does appear to describe warmth entering the building from another source he says that the heat from the furnaces kept the whole building warm (we wept 304)

I tend to believe this is true since there was little other than an elevator shaft and a door between LK1 and the cremation room. But it would only be warm relative to the freezing outside, right?

“I think it would be dangerous to heat the room during gassing.”
Why if it was not dangerous in the case of de lousing?

For delousing it was normal to use a dedicated circulation device that moved hot air through a chamber. In this way no HCN leaves the system. This is what was done at Majdanek, Dachau, etc. The system suggested at LK1 is an external ventilation system, with air supplied from the forced-draft devices and (necessarily) removed through an exhaust. I would fear the HCN gas diffusing backwards through the ventilation system. At the same time, HCN would be going out the exhaust, which would at least be wasteful.

one relevant point comes from Green’s discussion of HCN solubility his Henry’s law calculations show that at a given HCN gas partial pressure increasing temperature decreases the equilibrium amount of HCN dissolved in water so heating does make the “aqueous HCN reservoir” smaller, all else being equal

Thus agreeing with Rudolf.

there is also another consideration when discussing the moisture supplied by people body fluids and waste products are not necessarily chemically neutral urine is normally somewhat acidic with a typical pH range of roughly 4.5–8.0 and an average around 6.0. Sweat is also generally weakly acidic, commonly falling somewhere around pH 4.5–7.0 human feces can also be mildly acidic one commonly cited average is around pH 6.6 although fecal pH varies substantially depending on diet and other factors [...]

You may be the first person to ever suggest that Prussian Blue formation was inhibited by poop. I will pass over this in silence.

I wouldn’t claim that the weak acidity of sweat urine or other biological material would by itself prevent Prussian blue formation the point is much more modest if acidic moisture was present it could reduce the fraction of dissolved cyanide present as CN- when considered alongside temperature HCN solubility moisture availability reaction kinetics and the availability of suitable iron species it becomes another variable that would need to be accounted for rather than simply assuming that moisture automatically produces sufficient CN- for Prussian blue formation

Okay, but isn't this idea pretty far out there? What's to stop me from suggesting that the delousing chambers had clothing soaked with sweat and other forms of acidic moisture to an equivalent degree?

My understanding is also that Prussian blue is not an inevitable or necessary by product of every use of HCN for fumigation its formation can depend on the particular environmental and material conditions so I think it is reasonable to treat the question of whether the historical conditions were sufficient to produce the observed Prussian-blue staining as a matter requiring expert chemical interpretation rather than as something that can simply be demonstrated from first principles alone

That might have been a very sound and sensible approach to this question, back before the people involved in raising it were defamed and put in prison!

I think Rudolf has very wisely not put all his eggs in the chemistry basket, but I also in observing these debates have yet to see any persuasive argument against PB formation in the gas chambers. That's why in 2026 we are still coming up with novel theories as to how PB formation was inhibited.