Canoes. Dugout canoes are still the main means of water transportation in West Africa. Dugout canoes, each made from a single tree, were seen by European explorers in the fifteenth century and had apparently been in use for centuries. In the latter part of the fifteenth century Europeans who traveled on the Niger River reported seeing canoes made from the trunks of two large trees that had been hollowed out and joined together across the middle. A midseventeenth- century explorer of that river said that his three camels were carried in one such canoe. Used widely over hundreds of miles on the Niger, canoes changed little over the centuries. Leo Africanus also described canoe travel during his 1513-1515 journey through West Africa. He wrote that, after 15 June, the Niger River flooded for forty days, creating good conditions for merchant...