THE OUMU, BERTA, AND LEOA MOUNTAINS. 810 Tho Bt^rta Mountains, followed by those of the Ijoga, whoso highest tulu or sunnnit.4 cxcetKl 10,000 feet, although their mean height is said to be scarcely 5,000 feet, stretch sijuth wards towards the sources of the Sobat affluents, rejoining tho Kaffa plateau by intermediary ranges which have not yet been explored by European travellers. But to the north the heights gradually lessen ; the inter- mediary plains bi"oaden out and unite, and the ranges are merely indicated by isolated rocks cwjjping out above the lowlands in continually decreasing numbers. West of the Fazogl country one of these isolated heights, the lofty Jebel-Tabi, partly covered with forests, attains a height of over 4,330 feet. Still farther on the red granite cone of Jebel-Guleh, that is to* say, " Mount of Woods," or " Mount of Ghouls," according to Mamo, which the Fuuj designate as the cradle of their race, attains a height of 2,820 feet. Still more to the west is a chain of rocks in the midst of the steppes which border the right bank of the White Nile. The highest is that of Defafang, which was till recently an ethnical limit between the country of the Denka Xegroes and that of the Abu-Rof Arabs. Tho two riverain zones of the White and Blue Nile, on each side of the Mesopotamia of Sonaar, are extremely fertile, thanks to the rainfall and the alluvia brought down by these rivers. But the intermediary region, which forms the base of the scattered rocks, presents in many places the appearance of a steppe. The land is covered with tall grasses, from the midst of which spring mimosas with their slight and delicate foliage. The populations, sedentary on the river bank, are nearly all nomad in the grassy plains surrounding the mountains of the peninsula. East of the lower valley of the Blue Nile the plains are analogous in character. Wooded and fertile along the river banks, they become bleak and barren away from the watercourses. In the level region of Gedaref, between the Rahad and the Atbara, trees are rarely seen. The most remarkable of the isolated masses scattered amongst the steppes east of the Blue Nile is that of Abu-Ramlch, or " Father of the Sands," scarcely 1,660 feet high, but flanked by suijerb towers piled up -in enormous masses. From the interstices of these rocks spring baobabs, their branches waving over the abyss, whilst hero and there some hut, to which distance gives tho ap])earanee of a bee-hive, nestles between the cliffs at the base of the gigantic tower. In the northern steppe, Jebel-Arang, the most advanced mountain, which attains an absolute height of but 2,000 feet not far from the right bank of the lower Rahad, is mainly covered by forests containing baobabs, which here reach their northern limit. On the eastern side the Jebel-Arang is followed by the Jebel- Abash ; then to the south the plain is studded with other heights, solitary or grouped, some of granite but nearly all of volcanic origin ; some are even topped by basalt columns affecting the divers forms of peristyles, pyres, or diverging facets. These heights in the midst of the ste])pes receive considerably more rain than the plains, and the water running rapidly over the slopes is absorbed by the sand and gravel surrounding the rocky escarpment. In order to obtain water during the dry season, the natives pierce the earth at the mouth of the ravines, and the pools thus formed, usually surrounded by trees, are named kharif from the rainy season which fills them. In the drie<l-up river beds the crocodiles
