Map of central Africa, with portraits of European explorers, 1854.
© Science Museum / Science & Society Picture Library
Engraved frontispiece by F Moras, designed by August Heinrich Petermann (1822-1878). In the four corners are members of an expedition which took place between 1850 and 1853: James Richardson (1809-1851), Eduard Vogel (b 1829), Heinrich Barth (b 1821) and Adolf Overweg (1822-1852). Illustration from Petermann's 'An account of the progress of the expedition to Central Africa', published in London in 1854.