All the way we are following what is known as a “mashrab,” a desert road, which consists of a narrow rut about a foot wide, worn by the passage of camels through many centuries. Without specially looking for them one would hardly notice these mashrabs, which are almost identical to the “gazelle paths” that wind aimlessly about the desert, but one is helped by the cairns of stones which are raised by the Arabs on every bit of high ground, sometimes to show the way and sometimes to mark the lonely grave of a less fortunate traveller. Each of these twisting desert tracks is known to the Arabs by a different name. There is the “Mashrab el Khamisa,” from Bagbag to Siwa, called thus because there are five wells on the way; there is the “Mashrab el Akhwan”—the Brothers’ Road, from Jerabub to the coast, which was used by the Senussi Brethren when they travelled from their Zowia at Jerabub into Egypt; and the “Mashrab el Abd”—the Slave’s Road, as according to legend, once upon a time, in the dim ages, a slave who was captured and brought by this route into Egypt from his home in the west, returned to the west and led an army against Egypt by the very road that he had come by as a captive. Often the mashrab seems to fade away, and then the trackers have to ride on ahead and pick it up again. A number of Bisharin from the North-East Sudan were specially enlisted in the Camel Corps as trackers and guides. They are thought to be more skilful at this work than any other tribe, though personally I think a bedouin is cleverer. But when working in a bedouin country it is best not to employ local natives. Some of the Bisharin are almost unnaturally clever, they can follow a footstep over hard, broken ground where anyone else would see no sign of anything. These men have a natural instinct for finding the way, a sort of abnormal bump of locality. When they first arrived on the coast some of them were wearing the usual clothes of their country and the fuzzy-wuzzy coiffure that is so remarkable a characteristic of their race. The Arabs had never seen this type of Sudanese and were intensely interested in them. Small bedouin boys used to stand and stare at these tall brown men with the great mops of woolly hair ornamented with a few skewer-like objects, but the Bisharin were absolutely indifferent. _28th._ Left “Keimat en Nus”—the half-way tent—at a very early hour and rode for a long time by moonlight; one can cover more ground when it is cold, but there is a danger of going off the track. The mashrab is faint enough in the daytime, but almost invisible at night. When we start off in the morning all the men shout together three times, “Ya Sidi Abdel Gader,” invoking a certain sheikh who is the patron sheikh of travellers. One of my men told me that he was born in Berber “min zaman”—a long time ago—and used to travel about the Sudan deserts without water or food. His descendants still live at Berber where he is buried.