ANGOLAN RIVEBS. 7 tljoir sources beyond the region directly subject to Portuguese rule, intermingling their AckkI waters with those of the Zuml)ese and of the Ku-]iango on a plateau which has a mean altitude of not less than 5,500 feet. The farthest source of the mainstream is the little Lake Mussonilx), some 720 miles from the coast, by the windings of the fluvial valley. From this point the Cuanza descrilx's a vast semicircle, flowing at first towards the north-east and then to the north, after which it sweeps round to the north-west and west, finally trending to the south- west in its last meander seawards. More than half of its course lies to the east of the upland terraces and plateaux which form the backbone of Angola. By the direction of its ui)per valley it seems inclined to become a tributary of the Congo, but on reaching the Ba-Songa territory, where it has already become a copious stream, it curves round to the west, and forces its way over a long series of wild goi'ges, falls and rapids, through the intervening mountain barriers seawards. The Cambambe cataract, last of the series, 70 feet high, is also known as the
- Livingstone falls," although never visited by the illustrious explorer. It is
formed by a ledge of schistose rock confined on both sides by nearly vertical walls. During the floods the whole gorge is completely filled with the seething waters, but during the dry season the current is broken by projecting crags into several foaming channels of unequal size. The emerged rocks, damp with the 8])ray of the tumbling waters, are overgrown with the Atigohea fluitann, a plant with large semi-transparent stem and covered with smuU white flowers. Immediately below the cataracts the Cuanza is accessible to steamers, no obstacle interfering with the navigation all the way to the sea, although in this section of the river, about 120 miles long, there is a total fall of over 300 feet. The rocky gorge is continued for 10 miles beyond the rapids, between high red, white, or bluish cliffs, to which an endless variety of shades and forms is added by the climbing plants, tufted brushwood, and drapery of velvet mosses. Below the gorge the main stream is joined by the Mucoso, a considerable affluent from the north, and farther on, also on the right bank, by the still more copious Lu-Calla (Lua-Kalla), largest of all its tributaries. Like the Cuanza itself, the Lu-Calla rises to the east of the Angola highlands, and like it forces its way through them in a series of gorges where it plunges in its headlong course from fall to fall. The Lianzundo, one of these falls, is no less than 100 feet in height. The Lu-Calla also describes a vast semicircle, but exactly in the contrary direction ro that of the Cuanza, for it takes its rise in the northern part of the Portuguese possessions, not fur from the streams which flow on the oppo- site watershed down to the Congo. After its junction with the Lu-Calla, the Cuanza is swollen by no further contributions from any direction, but on the contrary discharges its waters to the right and left, into numerous lagoons or lateral reservoirs, which are succes- sively flooded and almost completely emptied with the alternating wet and dry seasons. In the lower reaches the hills continually recede more and more from the fluvial bed, although a few bluflFs stiU rise here and there along the banks of the river. One of these on the left side is the famous Pedro dos Feiticeiros,
