the shelter of the Dum palms; thousands of sand grouse arrive morning and evening to drink and to depart.” In the pools of the Atbara Baker for the first time shot hippopotamuses. He also started fishing with a rod and line, and on one occasion caught an enormous “turtle.”[77] At the end of June they were nearly suffocated with the heat and dust of the Sudan summer, but they were to experience the effects of the melting of Abyssinian snows and of the descent of the tropical rains on that African Switzerland. On the 24th of June Baker was lying half asleep on his bed by the margin of the river when he fancied he heard a rumbling sound like distant thunder. This roar increased in volume till it awoke his Arabs, who rushed into the camp shouting, “The river! The river!” “We were up in an instant, and my interpreter in a state of intense confusion exclaimed that the river was coming down, and that the supposed distant thunder was the roar of approaching water.... Many of the people were sleeping on the clean sand of the river’s bed, and were only just in time to reach the top of the steep bank before the water was on them in the darkness.... The river had arrived ‘like a thief in the night.’ When morning broke I stood upon the banks of a noble river, the wonder of the desert! Yesterday there was a barren sheet of glaring sand with a fringe of withered bush and trees upon its borders.... No bush could boast of a leaf, no tree could throw a shade: crisp gum crackled upon the stems of the mimosas.... In one night there was a mysterious change.... An army of water was hastening to the wasted river, which had become a magnificent stream some five hundred yards in width and fifteen to twenty feet in depth. Bamboos and reeds with trash of all kinds were hurried along the muddy waters.... I realised what had occurred: the rains were falling and the snows were melting in Abyssinia. These were the main source of the Nile floods.” Baker left the Atbara in a land of wild asses and gazelles, and travelled to Kassala,--a fortress of the eastern Sudan since rendered famous by the struggle for its possession between Dervishes and Italians. Kassala is situated on the right bank of the river Mareb, which rises close to the Red Sea on the northern slopes of the Abyssinian plateau. The Mareb has every intention of reaching the Nile, or rather the Atbara, and no doubt did so in past epochs; but at the present time northwards of Kassala it loses itself in the desert.