([lemma=must] [tag=□])? □
([lemma=must] [tag=VB])? □
During the period when the fires were kept continously burning without a break , the ashes fell through the grates and were constantly removed and crushed to powder . April 11 , 1942 : a letter from an SS Major-General to the chief of Himmler 's personal staff describes how he has shot all the male Jews he could find , and will soon clear out the camp of women and children with the aid of a " delousing van " ( Entlausungswagen ) . Here , he wishes to prove that there were gas vans in Riga , and since this letter discusses constructing " Vergasungsapparate " in Riga , they must be the same thing . Additionally , if he wants to claim that the gas chambers were cold with respect to outgassing of Zyklon , he must make the same assumption here . Blue from iron oxides from the construction materials and the developing cyanide in the walls on the occasion of HCN gassing , as I proposed , he considers it as unlikely , mainly because he considers the walls observed to be a pH neutral environment . " Today 's cutting-edge technology toys for toddlers are blurring the boundaries between the living and the mechanical .