"S INCE BEFORE THE TIME of the Prophet my clan has bred and raised camels on the green foothills of the Mountains of Nuba, in Kordofan, up above the White Nile," said Nyazi, as the galleot drifted langorously through the channel between Malta and Sicily. "When they are come of age, we drive them in great caravans down into Omdurman, where the White and the Blue Nile become one, and thence we follow tracks known only to us, sometimes close to the Nile and sometimes ranging far out into the Sahara, until we reach the Khan el-Khalili in Cairo. That is the greatest market of camels, and of many other things besides, in the world. Sometimes too we have been known to follow the Blue Nile upstream and cross over the mountains of Gonder into Addis Ababa and points beyond, even ranging as far as sea-ports where ivory-boats set their sails for Mocha.