130 The British Campaign in the Soudan.

tion) of the Nile, for being a rainless country, she depends upon her only river for her very existence. The experience of fifty centuries has proved that Egypt can never be safe unless she controls the banks of the Nile at least as far south as Khartoum.

From the sea to the mouth of the Atbara above Berber, a distance of one thousand seven hundred miles, not a single affluent falls into the Nile, and the breadth of its valley above the Delta varies from a mere rocky cafion to a very rare maximum of three to four miles, the average being under two. ‘Three million of people, being nearly one half of the population of Egypt and Nubia, are crowded into that narrow ribbon one thousand five hundred miles long by two in breadth, without any possible outlet, for all the vast spaces east and west (some eight hundred thousand square miles) are THE Desert.

Vegetation stops just where the waters of the Nile cannot be lifted by irrigation, and the dividing line between that and the desert is as sharply marked as a gravel walk | _ across a grass lawn. Between the Nile and the Red Sea is the Arabian Desert, and on the west, extending until it joins the Sahara, is the Libyan Desert.

Egypt proper extends only to the first cataract at Assouan, about seven hundred miles from the sea (lat. 24° 5’).

Between the first cataract at Assouan and the second cataract at Wady Halfa, the country is called Lower Nubia, and from Wady Halfa (lat. 22°) to New Dongola (lat. 18°) is Upper Nubia.

All the regions south of Dongola are embraced under the name of Soupan—an immense and indefinite region, stretching across the entire continent of Africa, on both sides of the equator, and subdivided by geographers into