88 SOUTH AND EAST AFRICA. only on rafts, except at the points where modem bridges and viaducts have been constructed. For about three-quarters of its whole course the Orange traverses the granitic plateau at a normal altitude of about 2,600 feet above sea-level. But its channel is suddenly lowered by over 400 feet through a series of cascades and rapids known as tho Aughrabies Cataracts or the " Ilundrod Falls," which occur a short distance bi'low the Ilartebeest confluence. For a space of about 16 miles the stream is here obstructed by innumerable reefs, ledges, islets, and even islands, some with low and smooth rocky surface, others bristling with sharp crags often affecting the form of towers or pinnacles. During the season of low water the stream ramifies into a labyrinth of torrents, lakes, pools, or silvery threads, all of which winding from circuit to circuit ultimately converge in the narrow and deep gorge below the falls. Some of these branches go to swell the volume of the great cascade with which the series terminates, while others develop independent falls of their own, tumbling over some lateral rocky bed in mimic rivalry with the main body of angry waters. " On every ciJe," remarks G. A. Farini, " fresh cascades sprang out as if by magic from the rocks. In fact, whether at high water or at low water, one of the p.culiar charms of the place is the extraordinary number of distinct waterfalls which exist here. At Niagara there are two gigantic cataracts falling side by side at one bound into the head of a gorge seven miles in length. Here there is a succession of cascades and falls — probably a hundred in number — extending along the whole length of a gorge no less than 16 miles long, into which they plunge one after the other, sometimes at a single bound, sometimes in a s.^ries of leaps. During the dry weather many of these cataracts are of great volume, but at wet seasons, when they &,re magnified a hundredfold, their mass must be immense. At Niagara the gorge is nowhere deeper than '200 feet, here the chasm is half as deep again." * This exi)lorer counted an 1 named nearly a, hundred distinct cascades, from which fact he named the whole 8*»ries the " Hundred Falls." To the last of the series he gave the name of the " Diamond Falls," having picked up half a dozen diamonds in some sand between the rocks at the foot of the gorge. Below the Hundred Falls the Orange is joined on its right bank, if not by a running stream, at le ist by a ramifying wady, which in the extent of its basin exceeds the Vaal itself. This is the Hygap, w^hich is formed by the Ub and the Nosob, or tho " Twins," so called because their parallel beds frequently converge in a single channel, by the Molopo, the Kuramen, and other fluvial valleys, which occasionally send it a little water. But although the total area of its drainage probably exceeds 180,000 square miles in extent, scarcely any of its numerous allluents are ever flooded for any length of time. When one is full another is dry, and ordinarily nothing is met except stagnant pools or meres, or just a little moisture, so that to obtain a supply of water travellers are often obliged to dig holes in the sandy depressions. * In any case, owing to the very slight incline of the surface in the Kalahari Desert, this fluvial system has been
- Thmigh the Kalahari Deaert, p. 417.
