After finishing his studies in humanities, he was hired as a private secretary by Pierre Savorgnan de Brazza (1852–1905), who in August 1888, entrusted Crampel with exploring the Ogooué north basin (mostly located in present-day Gabon).

In the following months, Crampel mapped over 2000 km of routes and signed several treaties with local African chieftains.

[2] In 1890 the Comité de l'Afrique française tasked him with an expedition to Lake Chad.

In September he disembarked at Bangui on the Ubangi River, the last outpost of French occupation, and trekked upcountry northward.

Several months later he reached the remote region of Dar al Kuti, roughly 500 km from the Ubangi (between 9 and 10 degrees North latitude).