Contains among other things: Memorandum on the foundation of the Usambara-Industrie-Gesellschaft, Berlin 1901

Contains among other things: Establishment of the experimental station Experiments to raise the cultures of the local population Sketch of the station's sites

Memorandum concerning the German school in Mlalo, 1910; Statuten der Schule, 1910; Chronik der Schule, 1908-1918; Korrespondenz, 1928-1939; Festschrift zur Einweihung der Friedrich-von-Bodelschwingh-Schule in Mlalo (Lwandai) with photo, 1931; Baupläne der Friedrich-von-Bodelschwingh-Schule, 1930; Festschrift zum 25-jährigen Jubiläum der Schule, 8 pp, Druck, 1933; Founded and first plans of the German Confederation, local group Usambara, March 1934; "School dispute mainly because of the so-called "racial question and correspondence on this, 1934-1935; "30 years Friedrich von Bodelschwingh School, 1938; "The Decades German School in Mlalo (Lwandai), 1938

Diary entries of Pastor Peter's travel experiences and conditions in Dar-es-Salaam and Usambara, as well as foundation and development of the mission work in Maneromango concerning Diary of Maaß concerning the construction of the mission station Maneromango (copies), 1896