The present study shows that in spite of the passage of a considerable period of time (over 45 years) in the walls of the facilities which once were in contact with hydrogen cyanide the vestigial amounts of the combinations of this constituent of Zyklon B have been preserved. This is also true of the ruins of the former gas chambers. The cyanide compounds occur in the building materials only locally, in the places where the conditions arose for their formation and persistence for such a long time.
In his reasoning Leuchter (2) claims that the vestigial amounts of cyanide combinations detected by him in the materials from the chamber ruins are residues left after fumigations carried out in the Camp “once, long ago”(Item 14.004 of the Report). This is refuted by the negative results of the examination of the control samples from living quarters, which are said to have been subjected to a single gassing, and the fact that in the period of fumigation of the Camp in connection with a typhoid epidemic in mid-1942 there were still no crematoria in the Birkenau Camp. The first crematorium (Crematorium II) was put to use as late as 15 March 1943 and the others several months later.