His major contributions are now seen as relating to source criticism of historical records, the understanding of West Africa, and as a perceptive historian of globalisation.
One set off under Captain James Alexander, but on calling at the Cape of Good Hope became involved in the Sixth Xhosa War, was diverted to South-west Africa, and proved financially burdensome for the RGS.
He rejected the existence of snow-covered mountains there, even after Karl Klaus von der Decken and Richard Thornton's return from Mount Kilimanjaro in 1863.
[2] A speaker of Kiswahili, which he had learned in London from a Zanzibari, Cooley was for many years supported almost solely by the civil list pension granted to him in 1859.
[4] In 1852 Cooley published Inner Africa laid open, an attempt to trace the major lines of communication across the continent south of the Equator.
[2] Cooley contributed to the Journal of the Royal Geographical Society, and wrote a series of controversial articles on African subjects to the Athenæum.