Gustaaf Adolf Frederik Molengraaff

As a student he made his first journey overseas when he joined the 1884–1885 expedition to the Dutch Antilles led by Willem Frederik Reinier Suringar and Karl Martin.

During his assignment in Amsterdam, Molengraaff travelled to South Africa to study gold deposits (1891) and to Borneo (1894) where he explored large parts of the inland.

This gave him time to write a report on the geology of the Transvaal, and travel to Celebes, where he (again) studied gold deposits.

[2][3] On the expedition he met Alexander Du Toit, both geologists were among the (at that time rare) supporters of Alfred Wegeners' continental drift theory.

Molengraaff was a close friend of W. F. Gisolf, who named his youngest son after him but died in a Japanese concentration camp.