An account of the caravan traffic from Timbuktu is given by Jackson, who says that Timbuktu "has from time immemorial carried on a very extensive and lucrative trade with the various maritime states of North Africa, viz., Marocco, Tunis, Algiers, Tripoli, Egypt, etc., by means of accumulated caravans, which cross the great desert of Sahara, generally between the months of September and April inclusive; these caravans consist of several hundred loaded camels, accompanied by the Arabs who let them to the merchants for the transportation of their merchandise to Fez, Marocco, etc., and at a very low rate. During their routes they were often exposed to the attacks of the roving Arabs of Sahara who generally commit their depredations as they approach the confines of the desert."[8] The wind sometimes rolls up the sand like great billows of the ocean, and caravans are often buried under the pile, and then the wind, shifting, scatters in the air those newly constructed mounds, and forms, amidst the chaos, dreadful gulfs and yawning abysses: the traveler, continually deceived by the aspect of the place, can discover his situation only by the position of the stars. When the caravans reach Akka, on the northern border of the desert, the camels and the guides are discharged, and others hired to proceed to Fez, Marocco, etc. The trip across the desert is made in about 130 days, including the necessary stops. Caravans go at the rate of three and one half miles an hour, and travel seven hours a day. The convoys of the caravan usually consist of two or more Arabs belonging to the tribe through whose territory the caravan passes. When the convoys reach the limit of their country, they transfer the caravan to other guides, and so on till the desert is crossed. The individuals who compose the caravans are accustomed to few comforts. "Their food, dress and accommodation are simple and natural: proscribed from the use of wine and intoxicating liquors by their religion, and exhorted by its principles to temperance, they were commonly satisfied with a few nourishing dates and a draft of water; and they will travel for weeks successively without any other food."[9] The caravans from Timbuktu were wont to export to the Barbary States gold dust and gold rings, ivory, spices, and a great number of slaves. "A young girl of Haussa, of exquisite beauty," remarks Jackson, "was once sold at Marocco, whilst I was there, for four hundred ducats, whilst the average price of slaves is about one hundred."[10] As to the cost of transporting the slaves, Jackson states that "Ten dollars expended in rice in Wangara is sufficient for a year's consumption for one person; the wearing apparel is alike economical; a pair of drawers, and sometimes a vest, forming all the clothing necessary in traversing the desert."[11]