Water Supply, 49 Kordofan is in consequence an arid unproductive land, with a sparse population, yielding a scanty revenue. To increase the water from the three sources above named, is the question on which depends the future value of the • province.

Colonel Colston's theory is as follows :—The wells of Rainfall. Kordofan are supplied only by the rainfall on its own area, as there are no mountains sending down their drainage, or any lake or river system filling the reservoirs by infiltration. On the north the rainfall is less, and the general level of the country lower ; on the east the Nile is 500 feet lower than any considerable area of Kordofan. On the south the regions of Nuba and Takalla generally drain south and east ; on the west Darfur is of a generally lower level, and separated from Kordofan by a waterless tract.

The supply of water is thus obtained from the rainfall on the upper porous stratum, which filters through to the impenetrable beds of mica schist, where it flows over the surface, and is collected in any depressions. If a well strikes one of these depressions, there is an unfailing supply of water ; if on the other hand it strikes the general surface, the supply is soon exhausted. The mean annual rainfall may be taken at 14 inches.

As might be expected, many wells become entirely dry, and most yield but little water late in the year. After the dokhn is gathered, whole villages migrate to the more permanent wells till the beginning of the rains. In El Obeid, where the supply is exceptionally large, water becomes an article of commerce, and late in the summer usually sells for 12 piastres (Egyptian) the vase of 1J to 2 gallons. Outside El Obeid there are no wells within a circle of 20 miles radius which can be relied on later than December, excepting: at Melbeis, 10 miles to the south. Water being thus so scarce, little is available for agriculture or stock raising.

Reservoirs have been established at certain places, Heserroin principally at El Obeid, where the natural drainage can fill them, and where the soil contains sufficient clay for their construction. They might be made on the watercourses which drain to Melbeis, and on those conducting water from near Abu Haraz, Melbeis, and Jebel Kordofan (386) e