Page:Africa by Élisée Reclus, Volume 3.djvu/529

GENERAL ASPECT OF THE CONGO BAS 435 good roads acc-ssible to wheeled traffic. So great are the difficulties of transport that a ton of merchandise, shipped at Antwerp for the Congo estuary at a freight of thirty shillings, is burdened with supplementary carriage charges of several hundred, or even several thousund, shillings before reaching the Arawhimi con- fluence. Hence, no serious attempt can be made to open up the vast resources of the Congo basin until the lower rapids are turned by good roads or railways. The direction and general course of the rivers is explained by the continental relief within the Congo basin, where the high land lies not in the central regions but in the neighbourhood of the seaboard. East of the Atlantic coast ranges stretches a central depression, which may be regarded as roughly limited west and north above Stanley Pool by the great bend of the main stream itself as far as the Stanley Falls, southwards by the Kassai and Sankuru rivers, and towards the east by the ranges skirting the west side of Lake Tanganyika. Within this vast space, which is probably of lacustrine origin, the Congo has room to develop an immense semicircle in a northerly direction. From all quarters of the compass streams converge on this central basin with remarkable uniformity, determined by the general slope of the land. Korth of Lake Lanji the Upper Congo affluents descend from the eastern and western ranges ; on the south the Sankuru-Kassai tributaries flow all in parallel channels northwards; on the west the streams traversing the French possessions follow an eisterly course to the right bank of the Congo. The Atlantic coast ranges north of the estuary are continued southwards in the same south-easterly direction, and consist of the same granite, gneiss, and primi- tive schistose recks, with a mean altitude of not more than 2,300 feet. From any of the summits commanding the Congo Valley on the south scarcely any eminences are visible on the horizon rising higher than the observer's standpoint. The whole surface is carved into deep gorges through which wind the converging streams, while the ranges rise gradually southwards. West of the Middle Kwango some of the crests exceed 3,000 feet, while about the headwaters the plateau itself stands at an elevation of considerably over 5,000 feet. But towards the east the surface assumes an almost horizontal aspect, and here lies the lacustrine parting line, which sends its overflow on the one hand through the Kassai-Congo to the Atlantic, on the other through the Zambese to the Indian Ocean. The greater part of the western region of hills and plateaux is overlaid with a thick layer of laterite formed by the disintegration of the argillaceous schists and other surface rocks, and presenting the appearance of many-coloured brown, red, and yellowish sands, through which the running waters percolate as through a sieve. East of the basin the relief is less regular than on the west side, the border chains being disposed less uniformly, but at some points attaining a greater altitude. The amphitheatre of hills south of Lake Bangweolo culminates in the Lokinga peaks, which are said to range from 8,000 to 10,000 feet, and which are connected by lateral spurs with the Yiano hills, pierced by the Lua-Laba and continued north-eastwards in the direction of Tanganyika. South of the Viano terraces the Lokinga mountains fall gradually north-eastwards, merging at last in