page_title: Evidence and documentation for the Holocaust
section_title: Use of gas chambers
hierarchical_section_title: Evidence and documentation for the Holocaust / Use of gas chambers
caption_attribution_description: Polski: Ruiny komory gazowej Krematorium II w obozie koncentracyjnym Auschwitz II (Birkenau) English: Ruins of the gas chamber of Crematorium II in in the concentration camp Auschwitz II (Birkenau)
context_page_description: The Holocaust—the murder of about six million Jews by Nazi Germany from 1941 to 1945—is the most well-documented genocide in history. Although there is no single document which lists all Jewish victims of Nazi persecution, there is conclusive evidence that about six million were killed. There is also conclusive evidence that Jews were gassed at Auschwitz-Birkenau, the Operation Reinhard extermination camps, and in gas vans, and that there was a systematic plan by the Nazi leadership to murder them.
  Evidence for the Holocaust comes in four main varieties:
  Contemporary documents, including a wide variety of "letters, memos, blueprints, orders, bills, speeches," Holocaust train schedules, statistical summaries generated by the SS and photographs, including official photographs, clandestine photographs by survivors, aerial photographs, and film footage of the liberation of the camps. More than 3,000 tons of records were collected for the Nuremberg trials.
context_section_description: Despite the difficulty of finding traces of this material 50 years later, in February 1990, Professor Jan Markiewicz, Director of the Institute of Forensic Research in Kraków, redid the analysis. Markiewicz and his team used microdiffusion techniques to test for cyanide in samples from the suspected gas chambers, from delousing chambers, and from control areas elsewhere within Auschwitz. The control samples tested negative, while cyanide residue was found in high concentrations in the delousing chambers, and lower concentrations in the homicidal gas chambers. This is consistent with the amounts required to kill lice and humans.
  The search for cyanide in the bricks of buildings said to be gas chambers was important, because the pesticide Zyklon B would generate such a residue. This was the gas most often cited as the instrument of death for prisoners in the gas chambers, supported by both testimony and evidence collected of Nazi policy.
  Another claim made by Holocaust deniers is that there were no specially-constructed vents in the gas chambers through which Zyklon B could be released. The BBC offers a response showing that this requires disregard of much documentation:
  Deniers have said for years that physical evidence is lacking because they have seen no holes in the roof of the Birkenau gas chamber where the Zyklon was poured in. (In some of the gas chambers the Zyklon B was poured in through the roof, while in others it was thrown in through the windows.) The roof was dynamited at war's end, and today lies broken in pieces, but three of the four original holes were positively identified in a recent paper. Their location in the concrete matches with eyewitness testimony, aerial photos from 1944, and a ground photo from 1943. The physical evidence shows unmistakably that the Zyklon holes were cast into the concrete when the building was constructed.
  Cremation in the open at the Reinhard death camps (Treblinka, Sobibor and Belzec) was discussed at Nuremberg on the 7 April 1946 by Georg Konrad Morgen, SS judge and lawyer who investigated crimes committed in Nazi concentration camps. He stated: "The whole thing was like an assembly line. At the last stop they reached a big room, and were told that this was the bath. When the last one was in, the doors were shut and the gas was let into the room. As soon as death taken place in (sic), the ventilators were started. When the air was breathable, the doors were opened, and the Jewish workers removed the bodies. By means of a special process which Wirth had invented, they were burned in the open air without the use of fuel."
  There is well-documented evidence that other ash was used as fertilizer in nearby fields. Photographs of Treblinka taken by the camp commandant show what looks to be ash piles being distributed by steam shovels.
  The Nizkor Project and other sources have stated that the minimal concentration of Zyklon-B to be explosive is 56,000 parts per million, while the amount used to kill a human is 300 parts per million, as is evidenced in "The Merck Index" and the "CRC Handbook of Chemistry and Physics". In fact, the Nazis' own documentation stated "Danger of explosion: 75 grams of HCN in 1 cubic meter of air. Normal application approx. 8–10 grams per cubic meter, therefore not explosive."
  The Institute for Historical Review publicly offered a reward of $50,000 for verifiable "proof that gas chambers for the purpose of killing human beings existed at or in Auschwitz." Mel Mermelstein, a survivor of Auschwitz, submitted his own testimony as proof but it was ignored. He then sued IHR in the United States and the case was subsequently settled for $50,000, plus $40,000 in damages for personal suffering. The court declared the statement that "Jews were gassed to death at the Auschwitz Concentration Camp in Poland during the summer of 1944" was a fact.
caption: The ruins of the Crematorium II gas chamber at Auschwitz-Birkenau.
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