René Caillié,
Travels through Central Africa to Timbuctoo and across the Great Desert to Morocco performed in the year 1824-1828…
(1830)
“ Such an enterprise, if successful would not be without profit to our commercial industry; and, considering it with respect to the sciences, what an inexhaustible source of discovery would it not open to natural history, natural philosophy, climatology, physical geography, and mathematics! What an immense field for a knowledge of the races of mankind, for the history of the civilization of nations, for that of their language, of their manners, and of their religious opinions! ”

