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 which bounds the western edge of the Uganda plateau, and follows a north and south line for nearly 1,000 miles.

The two systems unite at the north end of the Albert Nyanza, whence their combined waters issue as the river called, in its upper reaches, the Bahr-el-Gebel, and afterwards the White Nile. It has been stated that the Victoria Nyanza system is the principal source of the Nile. About this there can be no two opinions. This lake, occupying an immense depression in the centre of a wide plateau, bounded on all sides by mountain ranges, naturally receives the drainage of the entire area. The tropical rainfall which for some three-quarters of the year deluges this region forms the source of supply. Lake Victoria is fed by numerous rivers, which drain the uplands. Its principal affluent is the Kagera, by some considered to be the real source of the Nile. This important stream rises some three degrees south of the equator, in the wild and remote country adjacent to the chain of volcanoes which bars the 'Rift' valley across, between the lakes of Albert Edward and Kivu. Further south than this the Nile sources cannot, by any stretch of imagination, be located, as these mountains form the watershed between the streams flowing south into Lakes Kivu and Tanganyika, and those flowing north to feed the Nile.

The outlet by which the Nile leaves the Victoria Nyanza is situated at the north-west corner of the lake. Here it falls over the rocky barrier of the Ripon Falls, with a drop of some 15 feet. The river, from this point to its junction with Lake Albert, is called the Victoria Nile.

The catchment area of the Albertine system is smaller than that of Lake Victoria, as the 'Rift' valley is narrow and enclosed by high mountain ranges. One source of supply, however, exists here which is wanting in the eastern system—namely, that derived from the melting of the snowfields and the glaciers of Ruwenzori. This range, known to the earlier geographers as the