published under the superintendence of the Society for the Diffusion of Useful Knowledge ; engraved by J. & C. Walker. Map of West Africa, Central: Bight of Benin to Lake Tchad. Relief is shown in hachures. Plate 124 from: Maps of the Society for the Diffusion of Useful Knowledge. London : Chapman and Hall, 1844. Imprint on map: London : Published by Chapman & Hall, 186, Stand, April 15th 1839.