178 JOURNEY TO CENTRAL AFRICA.

little ridges of sand, with rough head and foot stones. He sat by one which he had just made. As I came up he informed me that all travellers who crossed the Nubian Desert, for the first time, are here expected to pay a toll, or fee to the guide and camel-men. " But what if I do not choose to pay ? " I asked. " Then you will immediately perish, and be buried here. The graves are those of persons who refused to pay." As I had no wish to occupy the beautiful mound he had heaped for me, with the thigh-bones of a camel at the head and foot, I gave the men a few piastres, and passed the place. He then plucked up the bones and threw them away, and restored the sand to its original level.* The Balir bela Ma spread out before us, glittering in the hot sun. About a mile to the eastward lay (apparently) a lake of blue water. Reeds and water-plants grew on its margin, and its smooth surface reflected the rugged outline of the hills beyond. The Waterless River is about two miles in breadth, and appears to have been at one time the bed of a large stream.

* Burckhardt gives the following account of the same custom, in his travels in Nubia : " In two hours and a half we came to a plain on the top of the mountain called Ahabet el Benat, the Rocks of the Girls. Here the Arabs who serve as guides through these mountains have devised a singular mode of extorting presents from the traveller; they alight at certain spots in the Akabet el Benat, and beg a present; if it is refused, they collect a heap of sand, and mould it into the form of a diminutive tomb, and then placing a stone at each of the extremities, they apprise the traveller that his tomb is made ; meaning, that henceforward, there will be no security for him, in this rocky wilderness. Most persons pay a trifling contribution, rather than have their graves made before their eyes ; there were, however, several tombs of this description dispersed over the plain."