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Rh or rather less than half that of the Nile. The main channel is clearly marked from beginning to end. The river takes its rise in 11° 21′ 3″ S., 24° 22′ E. The source lies in British territory in a depression of an undulating country 5000 ft. above the sea, covered with bracken and open forest. The water, like that of all the rivers of the neighbourhood, issues from a black marshy bog, and quickly collects into a well-defined stream. In the first hundred miles of its course the river is known as the Yambeshe—in sound almost identical with its name in its lower course, though intervening sections are known as Liambeshe, Liambai, &c. Eastward of the source the water-parting between the Congo and Zambezi basins is a well-marked belt of high ground, falling abruptly north and south, and running nearly east and west between 11° and 12° S. This distinctly cuts off the basin of the Luapula (the main branch of the upper Congo) from that of the Zambezi. In the neighbourhood of the source, however, the water-parting is not so clear, but the two river systems do not connect.

The Upper River.—The infant Zambezi, after pursuing a south-westerly course for about 150 m., turns more directly south and, soon after the 12° S. is crossed, is joined by a stream (coming from the north-west) whose source is near a marshy lake called Dilolo, 4600 ft. above sea-level in 11° 50′ S., 22° 10′ E. Lake Dilolo was at one time believed to communicate with the Kasai river, one of the great affluents of the Congo flowing north-west, but this is not the case. Dilolo belongs to the Zambezi system only, sending water to that river after heavy rain. The Zambezi as it flows southward receives on either side numerous small tributaries. A few miles above Kakengi (in 12° 24′ S.), the Zambezi, narrow, picturesque and tortuous, suddenly widens from 100 to 350 yds. Below Kakengi are a number of rapids ending (13° 7′ S.) in the Sapuma cataracts. At this point the river flows tumultuously through a rocky fissure.

The first of its large tributaries to enter the Zambezi is the Kabompo, a left-hand affluent. It joins the main stream in 14° 26′ S. A little lower down (in 14° 18′ S.) the Zambezi receives from the west the waters of a much larger stream than the Kabompo, namely, the Lungwebungu. (For details concerning these and the other chief tributaries of the Zambezi, see below.) The savannah forest, which has hitherto characterized the country, now gives place to a more open bush valley, studded with Borassus palms. Dense vegetation is confined to narrow strips of matted forest which skirt the first few hundred yards of the sources of the Zambezi and its tributaries during the first 100 m. or so. The land, from 5000 ft. at the source, falls gradually to 3600 ft. at Kakengia distance of 220 m. From this point until the Victoria Falls are reached—500 m.—the level of the Zambezi basin is very uniform, the fall being in this distance 600 ft. only. Twenty miles below the confluence of the Lungwebungu the country becomes flat, and in the rainy seasons is largely covered by floods. Some 50 m. farther down, the Luanginga, which with its tributaries drains a large area to the westward, joins the Zambezi. A few miles higher up on the cast the main stream is reinforced by the waters of the Luena. On the same (eastern) side a little below the junction of the Luanginga and the Zambezi stands Lialui, the capital of the (q.v.). The river, which for some distance has had a slight western as well as southern trend, now turns distinctly south-east. From the cast the Zambezi continues to receive numerous small streams, but on the west is without tributaries for 150 m., when the great river formerly misnamed the Chobe, but known to the natives as Kwando or Linyante, joins it (in 17° 47′ S.). Before this junction is effected, the Gonye Falls, the work of erosion (16° 40′ S.), offer an interruption to navigation, whilst below the falls are numerous rapids. The western bank of the Zambezi, which in this part of its course is very tortuous, is German territory from the most southern of these rapids—Katima Molilo (17° 28′ S.)—to the confluence of the Kwando, including the right or northern bank of the lower course of the last-named river; this narrow strip of land projecting from the main portion of German South-West Africa expressly to allow Germany access to the Zambezi.

Below the junction of the Kwando and the Zambezi the river bends almost due east. The stream has hitherto flowed, in the main, in a gentle steady current, the depth of water, owing to the breadth of the channel, not being great. But its character is about to change. As it flows eastward towards the border of the great central plateau of Africa it reaches a tremendous chasm in the floor of the earth, and thus the (q.v.), the largest waterfalls in the world, are formed.

The Middle Zambezi.—The Victoria Falls are reached some 60 m. after the Kwando confluence is passed, and below them the river continues to flow due east for about 120 m. It then cuts its way throuch perpendicular walls of basalt from 60 to 100 ft. apart. This dismal canyon, named by Major St Hill Gibbons “The Devil's Gorge,” is 8 m. long. Towering over the rocks which form the banks of the river are precipitous hills, 700 to 800 ft. high. The

river flows swiftly through the gorge, the current being continually interrupted by reefs. Beyond the gorge are a succession of rapids, ending with those called Molele, which is 146 m. below the Victoria Falls. In this distance the fall of the river is 800 ft. From the Devil's Gorge the Zambezi takes a decided trend north whilst still pursuing its general easterly course. For the next 700 m. until the Kebrabasa Rapids are reached, the river flows through well-defined and occasionally rocky banks. Besides the rapids already mentioned there are several others in the middle stretch of the river, forming impediments to navigation at low water. One of the most difficult passages is that of a grand gorge a little above the mouth of the Loangwa, in about 30° E., named by Major Gibbons Livingstone's Kariba, in distinction from a second Kariba ( = “gorge”) a little beyond the Kafukwe confluence. Between the two gorges the river is generally unobstructed, but at the western end of the second Kariba navigation is dangerous at low water. Exclusive of the (q.v.) the Loangwa and the Kafukwe (also called Kafue) just mentioned are the two largest left-hand tributaries of the Zambezi. The Kafukwe joins the main river in 15° 57′ S. in a quiet deep stream about 200 yds. wide. From this point the northward bend of the Zambezi is checked and the stream continues due east. At the confluence of the Loangwa (15° 37′ S.) it enters Portuguese territory, and from this point to the sea both banks of the river belong to that kingdom. At the Kebrabasa Rapids—800 m. below the Victoria Falls—the Zambezi is sharply deflected to the south, the river at this point breaking through the continental escarpment to reach the sea. The Kebrabasa Rapids, which extend about 45 m.—the road taking a detour of 70 m.—are absolutely unnavigable, and with them the middle stretch of the Zambezi as definitely ends as does the upper river at the Victoria Falls.

The Lower River.—The lower Zambezi—400 m. from Kebrabasa Rapids to the sea—presents no obstacles to navigation save the shallowness of the stream in many places in the dry season. This shallowness arises from the different character of the river basin. Instead of, as in the case of the middle Zambezi, flowing mainly through hilly country with well-defined banks, the river traverses a broad valley and spreads out over a large area. Only at one point, the Lupata Gorge, 200 m. from its mouth, is the river confined between high hills. Here it is scarcely 200 yds. wide. Elsewhere it is from 3 to 5 m. wide, flowing gently in many streams. The riverbed is sandy, the banks are low and reed-fringed. At places, however, and especially in the rainy season, the streams unite into one broad swift-flowing river. About 100 m. from the sea the Zambezi receives the drainage of Lake Nyasa through the river Shiré. On approaching the ocean, which it reaches in 18° 50′ S. the Zambezi splits up into a number of branches and forms a wide delta. Each of the four principal mouths—Milambe, Kongone, Luabo and Timbwe—is obstructed by a sand-bar. A more northerly branch, called the Chinde mouth, has a minimum depth at low water of 7 ft. at the entrance, and of 12 ft. farther in, and is the branch used for navigation. Sixty miles farther north is a river called the Qua-Qua or Quilimane, from the town founded by the Portuguese at its mouth. This stream, which is silting up, receives in the rainy season the overflow of the Zambezi.

The region drained by the Zambezi may be represented as a vast broken-edged plateau 3000 or 4000 ft. high, composed in the remote interior of metamorphic beds and fringed with the igneous rocks of the Victoria Falls. At Shupanga, on the lower Zambezi, thin strata of grey and yellow sandstones, with an occasional band of limestone, crop out on the bed of the river in the dry season, and these persist beyond Tete, where they are associated with extensive seams of coal. Coal is also found in the district just below the Victoria Falls. Gold-bearing rocks occur in several places.

Four Thousand Miles of Navigable Water.—As a highway into the interior of the continent the Zambezi, like all other large African rivers, in greater or less degree, suffers on account of the bar at its mouth, the shallowness of its stream, and the rapids and cataracts which interrupt its course. Nevertheless its importance to commerce is great, as the following recapitulation of its navigable stretches will show. (1) From the sea to the Kebrabasa Rapids, 400 m. (2) From Chikoa (above Kebrabasa) to within 140 m. of the Victoria Falls, 700 m. (3) From the rapids above the Victoria Falls to the Katima Molilo Rapids, 100 m. (4) Above the Gonye Falls to the Supuma cataract, 300 m. (5) Above the Supuma cataract, 120 m. Thus for 1620 m. of its course the Zambezi is navigable for steamers with a draught of from 18 to 28 in. Were the obstruction caused by the Kebrabasa Rapids removed, there would be a clear passage from the sea almost to the foot of the cataracts below the Victoria Falls. The difficulty at Kebrabasa might be removed either by the cutting of a side channel or the building of a dam to convert the gorge into a lake, to be connected with the river below by a lock and weir.

Several of the Zambezi affluents are also navigable for many miles. The Lungwebungu, which enters the upper river, is navigable for a long distance, thus supplying communication with the extreme north-west corner of the Zambezi basin. Parts at least of the Luena, Kafukwe, Loangwa and the Kwando tributaries are also capable of being navigated. The possibility of connecting the