Original correspondence consists of one letter each to Peter Pringsheim (1912); Joseph Koeth (1928); and A. Sommerfeld; as well as six letters to Ernst Stern (1907-1908). A handwritten 1933 letter from Fritz Haber to Chaim Weizmann in Mannern, Switzerland (6 pages) is available as a photocopy only. Also included is a typescript by Hans Schaeffer on Jews in Breslau (photocopy), Die soziale, politische und religioese Stellung der juedischen Familien in Breslau um die Jahrhundertwende 1900. The typescript is part of a letter by Hans Schaeffer to Johannes Jaenicke, also in the collection.