Page:Africa by Élisée Reclus, Volume 4.djvu/19

ANGOLAN UPIANDS. 5 in height, the highest points here falling below 6,000 feet. Farther west the summits, rising on a plateau inferior to the eastern terrace, also fail to reach the altitude of Mount Lovili and the neighbouring peaks, although several present an imposing appearance, thanks to their isolated position, and the steep slope of their flanks. Such are the crags which lie some 60 miles to the east of Uenguella, and which, from their peculiar outlines, have received the name of Binga-Yam-Bambi, or " Gazelle Ilorns." According to Magyar, they exceed 3,000 feet in height, while the neighbouring Olombiugo peak is said to attain an elevation of over 5,000 feet. The mori^ westerly summits, standing on the last terrace of the plateau as it falls seawards, vary in altitude from GOO or 700 to 2,000 feet. Developing at their base precipitous cliffs, they present in many places the aspect of veritable mountains. But most of the hills skirting the coast are mere table rocks, rising little more than 300 or 400 feet above the terraces. They are usually flanked by steep slopes of talus formation, but may be surmounted by following the long winding valleys of erosion, which have been excavated at intervals in the thickness of the plateau. In the southern region of the Angola territory, the uplands of the interior have everywhere been denuded and eroded to great depths, by the aflfluents of the Cunene and the torrents of the coastlands. Nevertheless the Chella, or Sierra da Neve, that is, " Snowy Range," a superb mountain mass to the east of Mossamedes, has maintained its integrity in isolated grandeur, some of its crests falling little short of 6,300 feet. It owes its alternative Portuguese name to the white streaks sometimes visible in the more elevated crevasses, after the heavy rains brought by the cold southern winds. These highlands, whence flow an abundance of running waters, appear to present the most favourable prospects for the future colonisation of Angola. The climate approaches, nearer than that of any other of the Portuguese possessions in Africa, to the conditions preailing in the south of Europe, while the mean altitude of the upland valleys is about the same as that of Angola generally, being approximately estimated at 4,000 feet. The Angola highlands arc composed of gneiss and other crystalline rocks under- lying schistose formations of great age. These rocks, forming the outer frame- work of the land, make their first appearance at a mean distance of from 1'2 or 15 miles from the coast. Here the sedimentary rocks, and in many places those of the interior, belong to the Secondary and Tertiary periods, consisting of sandstones, conglomerates, limestones, clays and sands generally disposed in perfectly regular stratifications. The cretaceous deposits, which run parallel with the coast, cover- ing the outer slopes of the hills in the BcngucUa district, abound in f( ssils identi- cal with those which occur in the corresponding formations in Portugal. For long stretches the characteristic geological strata are concealed by laterites, white, yellow, or red, of relatively modern origin, which have been foraied by the decomposed surface of the underlying layers. The river basins of the interior have moreover been strewn with alluvial deposits due to the action of running waters.