the letter from Dr. Sigmund Rascher to Himmler which proves that a gas chamber was built at Dachau

Some of the tour guides at Dachau tell visitors today that the gas chamber, located just outside the concentration camp, was used a few times to gas a small number of prisoners, although not for mass gassing.  Some of the guides tell visitors that the gas chamber was used to test combat gases on prisoners in the camp.  This claim is based on a letter that was written by Dr. Sigmund Rascher to Heinrich Himmler, in which Rascher mentioned that “the same installation as in Linz is to be built at Dachau” and that he wanted to use the new installation to test combat gases.