@KZadBhat #32631
But the gas chambers were easy: The first few experiments with gassing Russian POWs took place in a specially sealed room in the basement of Block 11. Max Grabner (well, him and Stark and several others, including that total and complete bastard Gerhard Palitzsch), the God-Emperor of Block 11, had sent his dull-witted Rottenführer, who didn't actually know what the Zyklon B was for at that point, I swear, to collect some cans of giftgas from the delousing station.
Stark and Grabner, along with two other men, dropped the pellets through holes in the ceiling onto some 650 Russian POWs and 250 sick Poles.
Lice, being cold blooded animals, required 15000 parts-per-million of Zyklon B to kill and it still took days. But humans would have eventually suffocated in that room, as even the denier admits, without any help at all. 330 parts-per-million of Zyklon B was all the "help" they needed to make the process efficient enough to repeat it in specially-constructed buildings*. And (a) before industrial incinerators existed there or (b) after they were built but were overtasked to handle the load of the - as of June 1942 - 2.5 thousand people a day the Sonderkommando were expected to incinerate, then the bodies were burned in pits as before.
Grabner's grinder monkey, the Rottenführer Pyschny, saw everything, and even helped shoot the first Sonderkommando group nominally tied to Block 11. He then put in his third transfer request and was given a penal transfer to a mine-clearing detail within an element of the Sixth Army on the Eastern Front in September, 1942.
*The Little Red House, or Bunker 1; and the Little White House, or Bunker 2 were early free-standing "gas chambers" which operated under command of Auschwitz I while Birkenau was being constructed. The incinerators and proper gas Chambers didn't go into operation until 1943, so the first bodies were burned and buried.
So, yeah, unfortunately the gas chambers did exist. I can't tell you with as much certitude what happened with them after 1942, but I have every reason to believe what the sonderkommando had to say on that matter. And Höß himself.