VICTORIA FALLS, rivalled only by Niagara in grandeur, form the most remarkable feature of the river Zambezi, Cen tral Africa. The falls are about midway in the course of the Zam bezi in 51' S., 41' E. For a considerable distance above the falls the river flows over a level sheet of basalt, its valley bounded by low and distant sandstone hills. Its clear blue waters are dotted with numerous tree-clad islands. These islands in crease in number as the river, without quickening its current, approaches the falls, whose nearness is indicated only by a veil of spray. At the spot where the Zambezi is at its widest—over 2,860 yds.—it falls abruptly over the edge of an almost vertical chasm with a mighty roar and a cloud of sun-lit spray. From 62 to ioo million gallons per minute fall over the edge.
The chasm, extending over the whole breadth of the river, is wider than Niagara, though broken, and it is more than twice the depth, a measurement varying somewhat, but attaining 420 ft. in the centre. Unlike Niagara the water does not fall into an open basin but is arrested at a distance of from 8o to 24o ft. by the opposite wall of the chasm. Both walls are of the same height, so that the falls appear to be formed by a huge crack in the bed of the river. The only outlet is a narrow channel cut in the barrier wall at a point about three-fifths from the western end of the chasm, and through this gorge, not more than ioo ft. wide, the whole volume of the river pours for 130 yd. before emerging into an enormous zigzag trough (the Grand Canon) which conducts the river past the basalt plateau. The tremendous pressure to which the water is subjected in the confinement of the chasm causes the perpetual mist which rises over the precipice. The fall is broken by islands on the lip of the precipice into four parts. Close to the right bank is a sloping cataract 36 yd. wide, called the Leaping Water, then beyond Boaruka Island is the Main Fall in two parts, 573 and 525 yd. wide beyond which is Livingstone Island and the Rainbow Falls 600 yd. wide. At both these falls the rock is sharp cut and the river maintains its level to the edge of the precipice. At the left bank of the river is the Eastern Cataract, a millrace resembling the Leaping Water. From opposite the western end of the falls to Danger Point, which overlooks the entrance of the gorge, the escarpment of the chasm is covered with great trees known as the Rain Forest ; look ing across the gorge the eastern part of the wall (the Knife Edge) is less densely wooded. At the end of the gorge the river has hol
lowed out a deep pool, named the Boiling Pot. It is some 500 ft. across; its surface, smooth at low water, is at flood-time troubled by slow, enormous swirls and heavy boilings. Thence the channel turns sharply westward, beginning the great zigzag mentioned. This grand and gloomy canon is over 4o m. long. Its almost perpendicular walls are over 400 ft. high, the level of the escarp ment being that of the lip of the falls. A little below the Boiling Pot, and almost at right angles to the falls, the canon is spanned by a bridge (completed in April 1905) which forms a link in the Cape to Cairo railway scheme. This bridge, 65o ft. long, with a main arch of 50o ft. span, is slightly below the top of the gorge. The height from low-water level to the rails is 420 ft.
The volume of water borne over the falls varies greatly, the level of the river in the canon sinking as much as 6o ft. between the full flood of April and the end of the dry season in October. When the river is high the water rolls over the main falls in one great unbroken expanse ; at low water (when alone it is pos sible to lock into the grey depths of the great chasm) the falls are broken by crevices in the rock into numerous cascades.
The falls are in the territory of Rhodesia. They were dis covered by David Livingstone on the 17th of November 2855, and by him named after Queen Victoria of England. Livingstone approached them from above and gained his first view of the falls from the island on the lip now named after him. In 186o Living stone, with Dr. (afterwards Sir John) Kirk, made a careful investi gation of the falls, but until the opening of the railway from Bulawayo (1905) there were but few visitors. The land in the vicinity of the falls is preserved by the Rhodesian government as a public park.