DESERT BIDE. 327 left behind, and nothing save the dim outlines of some hills near Akailot breaks the monotony of the sandy waste; the heat is great, and the sand so loose and deep that the camels can only proceed at a very slow pace. The tantalising mirage is a source of constant irritation, for although one knows full well what it is, yet it produces a very marked impression on the mind ; and causes one's thoughts to dwell upon the shady banks of wellknown rivers, and induces a constant craving for cool, good water, which is at times most painful.

When camping in the desert we found the Arab's advice to sleep with the head to the wind very good ; a small pile of goods should be placed as a wind-screen, for about 3 to 4 a.m. a cool wind often springs up, and if one is not protected from it illness is sure to ensue. The ground rises very gradually to Bir Oback, where there is a good supply of water. The sanddrifts at this place are constantly shifting their position, and would prove no slight obstruction to the proposed railway from Suakin to Berber ; but a little skill might doubtless overcome this difficulty.

After twenty-two hours more of gradual ascent, with low hills on either side, the small Arab village of Ariab is reached. This place lies amongst rocky hills, and the water is both plentiful and good. Here, there are again a little sparse