Working with the Ahnenerbe division, Wolfram Sievers, Bruno Beger and Hirt together collected human skeletons from among the Dachau inmates in order to create an anatomical specimen collection specifically of Jews. In 1943, Hirt had 79 Jewish men, 30 Jewish women, 2 Poles, and 4 "Asians" selected among the inmates at Auschwitz. These people were sent to Natzweiler-Struthof on July 30, 1943. Here they were gassed, by Josef Kramer, on August 17 and August 19, 1943. Their bodies were returned to Hirt at the anatomical laboratory of the Reich University in Strasbourg for preparation as an anthropological display, where they were re-discovered after the liberation.