Excerpts from the report of the voyage.
"When the research of S.M.S. Gazelle in the scientific area are presented to the public in this work, it has to be pointed out in the interest of their correct evaluation that the Gazelle could not dedicate herself exclusively to these studies, but that - like every other naval vessel - she had to serve military and political purposes as well."
....
"The German African Society for the Exploration of Central Africa, which in May 1873 had sent an expedition to the Loango coast that - as has been widely known - suffered bad luck from its beginning (wrecking of the Nigretia on 14 June 1873), had directed a plea to his Excellency the Chief of the Admiralty to support the purpose of the expedition and alleviate its fate through the occasional dispatch of a naval vessel to those regions. To respond to this request, S.M.S. Gazelle was to enter the mouth of the Congo River during her passage through the South Atlantic Ocean and in Banana act towards strengthening the expedition and the station Chichozo and, by undertaking observations, produce a basis of higher value for the studies of the station."
Hydrographisches Amt des Reichs-Marine-Amts (1889) Die Forschunsgreise S.M.S. "Gazelle" in den Jahren 1874 bis 1876. 1. Theil, Mittler, Berlin, 307 pp.