A very extensive book on the subject is Jean Claude Pressac: Technique and Operation of Gas Chambers
Zyklon B was used in Auschwitz (and Stutthof) It was originally a desinfection/delousing product used for empty buildings and prisoners' clothes etc. made by the pest control company Degesch and distributed by TESTA (Tesch und Stabenow) The book describes the history of the application of HCN gas from disinfection to lethal use. Another method of disinfection in camps which was used was heat and steam autoclaves. Zyklon B is HCN (hydrocyanic acid) absorbed in silcone pellets and does not smell but it originally had a chemical scent added. It was removed from the batches intended for lethal use. The documents requesting the shipments of this form of altered product had been used as evidence in the post-war forensic investigations. In gas chambers, the HCN pellets were dropped through columns onto "hot plates" as its boiling point is around 26 C. If you google any of the terms mentioned here, you are most likely going to find quite a bit of info. There are also excerpts online from Pressac's book.
WARNING! Content may be disturbing to some members!
Unfortunately, yes, I remember quite a bit about gassing prisoners. Though I am not very familiar with the Zyklon B method, as it was not used at my camp. We used the Nazi's initial method of gassing people, which was via modified vans with re-directed exhaust fumes.
I'm not sure of exactly where this method of execution was first employed, but it was brought about due mostly to the horrendous effects of mass shootings on the men. Mass shooting was far too personal, psychologically damaging, & expensive for the Reich to continue with. The idea of using actual gas chambers later spawned out of the fact that they wanted to be able to gas more people at one time than they could by using the vans.
This is why my camp (Chelmno) is not technically considered to be one of the "Reinhard Heydrich death camps". Those were the death camps created with gas chambers after the decision to use mass gassing as the preferred method of execution had been decided. Chelmno (where we always used gassing by van for mass execution) was more like a prototype of the later death camps.
I saw a movie about the holocaust a few days ago, and according to this historical record, canisters of gas were used to pipe in the carbon monoxide into the gas chamber. The canisters were shown, they looked much like the canisters that we use today for propane, or looking a bit like a small fire extinguisher. Here is a photo of the canisters
The T4 program, which started in 1939, used carbon monoxide gas from exhaust pipes, to kill mentally disabled people. It actually started after the parents of a severely disabled infant child, (from the Leipzig area), petitioned Adolf Hitler to allow the "mercy killing" of their son in 1938. The poor child was eventually killed. But this heralded the start of the use of gas to kill those who were deemed "life not worthy of life" in Nazi Germany.
As Laurasia says, Chelmno was kind of like the prototype of the later industrial scale death camps. Heydrich was indeed charged with organising the development and implementation of the policy of the Final Solution and he charged Adolf Eichmann with much of the logistical development, but in terms of the actual technical detail he had little part in that side of things. His successor in this area, Hans Kammler, was significantly involved in the design and detail. However, only Auschwitz had the funding to enable the most advanced "kit" to be developed. And Heydrich was dead before it all really took off. In fact there are some historians who suggest the term Operation Reinhardt was actually named after the Finance Minister Fritz Reinhardt and not Heydrich, (who had dropped the "T" from his name earlier). One would have thought any operation named after anyone senior would have used their surname, so it is far likelier that if it were to have been named after Heydrich it would have been called Operation Heydrich.
Quote from Wiki: " It is held by some, particularly German, historians that (Fritz) Reinhardt gave his name also to Operation Reinhard, although broader understanding especially after its termination has associated that program's name with Reinhard Heydrich..."
There was a program started to reduce unemployment called the "Reinhardt Program". So, due to the fact one of the key objectives of "Operation Reinhardt", was to grab the wealth from the poor souls who were transported to the camps it seems more likely that "Operation Reinhardt" was indeed named after a Finance Minister rather than the deceased head of the SD, despite the fact he had had the dirty job of organising significant elements of the Final Solution dumped on him by the Office of the Four Year Plan.
History has blamed Heydrich almost solely for much of the Final Solution. But there are some significant discrepancies out there. I found an instance on a reputable Holocaust site that stated categorically that Heydrich signed off the plans for Treblinka. It was in fact Himmler who signed them off. It's very easy to blame a dead man who cannot speak for himself for everything, although he was by no means innocent and would certainly have hanged as a war criminal at Nuremberg had he survived the war, ( if the war had gone the same way of course, which I feel it may not have if Heydrich had been sent into France to sort out their Resistance movement).
Anyway, back to the issue at hand. The main reason Auschwitz got the most sophisticated "kit" in this hideous area was because of the associated industry surrounding the camp. Treblinka and Sorbibor etc etc, (as well as Chelmno), were very different because there was no industrial dimension and therefore the Reich would not invest so much in technology for those facilities.
Zyclon B was originally used to fumigate clothes and bedding etc in the camps. It was widely used in general at the time, so seemed to be a readily available source of poisoned gas. Quote from Wiki: "Hydrocyanic acid was widely used for the fumigation of valuable tree crops. It was initially applied to citrus fruit in 1887 in California. Use spread to Spain and other countries using either liquid prussic acid, calcium cyanide, or sodium cyanide preparations. During World War I other HCN-based pest control applications were developed, and soon fumigation of ships, stores, factories, and even residential buildings with hydrocyanic acid gas became a popular method of combatting insect and rodent pests in many countries. Thousands of ships, cereal mills, and other food processing factories were fumigated with hydrocyanic acid gas until the mid-1930s in Germany alone."
In terms of who first used gas chambers it appears to have been the United States of America! In 1924 the Nevada Prison system came up with the idea of using cyanide gas to kill prisoners. So it was not actually a Nazi invention at all. They just took it to a whole other level.
It is also worth noting that ideas about "life not worthy of life" and Euthanasia were around in the USA and even in the UK at the time and even earlier. So it was by no means a purely German concept.
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