Supermind

Chemical Analysis (III) was next. The Chemical Analysis Section was scattered over several floors, with the first stages up above. Division III, Malone remembered, was devoted to nonpoisonous substances, like clay or sand found in boots or trouser cuffs, cigar ashes and such. They were placed on the same floor as Fingerprints to allow free and frequent passage between the sections on the problems of plastic prints, made in putty or like substances, and visible prints, made when the hand is covered with a visible substance like blood, ketchup or glue..FROM THE BOOKS.