Niger, a great river of Western Africa, whose head-waters rise amid the Kong Mountains behind Sierra Leone; flowing NE. as far as Timbuctoo (2 m. from the river), it there bends gradually southward, receives from the E. its great affluent the Benuë, and about 100 m. from the coast begins to form a wide forest and jungle-covered delta (larger than that of the Nile), and finally flows into the Gulf of Guinea by 22 mouths after a course of some 2600 m. Forms, with the Benuë, an invaluable highway into the heart of the country; its upper and middle parts, under the names Joliba, &c., are within the French sphere, and the lower portion below Say is under English authority.