African explorer, born at Thornhill, studied at Edinburgh University, and in 1878 was appointed zoologist to the Royal Geographical Society's expedition to Lake Tanganyika, which, after the death of the leader, Keith Johnston, at the start, he, at the age of 20, carried through with notable success; in 1882 explored with important geographical results Massai-land, and subsequently headed expeditious up the Niger and to Sokoto, and explored the Atlas Mountains; published interesting accounts of his various travels (1858-1895).