REGULATION OF WATER-SUPPLY 201 account of the low-lying marshes of enormous extent which a sUght rise of the water spills into.

This circumstance affects the river almost from its source, for the excess of Victoria Nyanza in the summer is soaked up in marshes on the Victoria Nile, while that of Lake Albert is disposed of in the regions of " sudd " on the Mountain Nile south of Lake No. The Bahr-el-Ghazal suffers similarly.

It is in the direction of controlling this treasure that improvement is coming ; but though schemes of dams and canals are being considered, the regulation necessary to irrigation is yet in its infancy, and meanwhile the Sudan of necessity more or less starves.

The dredging of the channel through the Zeraf is already in progress, and it is hoped that the improved carrying capacity of the channel, supplemented eventually by a dam retaining the surplus waters of Lake Albert, will supply the needs of Egypt ; this leaves the Blue Nile free for the purposes of the Sudan, which will naturally be directed to the Ghezireh, lying between the Blue and the White rivers, and long known for its productiveness. The latter part of the scheme, hi its fullest development, depends on problems which have yet to be solved, but in the meantime there is ample scope for effort in the initial stages of the work.

The three main contributing rivers are the Atbara, Blue Nile, and Sobat, in their order from north to south, and all rise in the hills of Abyssinia. The Atbara, being nearer the mouth, naturally wins