The author recounts an extended expedition through the Kasai basin of the Congo, combining travel narrative with ethnographic description. He details routes and river navigation, logistical arrangements and trading with local suppliers, and the process of collecting objects and natural specimens. The account presents portraits of diverse native communities, their material culture, ceremonies, social customs, and oral traditions, illustrated by drawings, colour plates, and a map. Reflections on fieldwork challenges, colonial administration, and commercial contacts provide contextual background for the observations.