PLATE XIX.

Lith. Sur. Dep. Cairo.

[Larger map] (330 kB)

PERENNIAL CANAL SYSTEM
OF
LOWER EGYPT

While basin irrigation is followed by the winter crops of wheat, beans, clover, barley, flax, lentils, vetches and onions, perennial irrigation allows of all the above winter crops and in addition the summer crops of cotton, sugar-cane, oilseeds, gardens and orchards. It will readily be understood that all this double cropping necessitates a very free use of manures.

It would be a healthy innovation indeed, if the provision of suitable manures were to be considered as an essential part of a project for providing perennial irrigation. The day is not far distant, I believe, when governments which provide irrigation works will also provide manures, and sell the water and the manures together, one being as essential as the other; I know well, from observation, that a well-manured field needs only half the water that a poorly manured field does; and in years of drought and scarcity manures almost take the place of irrigation. Why should there not be a manure-rate as well as a water-rate? Here in Egypt, the numerous ruins of old-world cities have hitherto provided manure for a great part of the perennially irrigated lands; but these are being fast worked out, and other sources must be sought for. Farm-yard manure will never suffice for the intense cultivation in this country. In connection with this subject, I can recommend the study of a remarkably able paper on “Nile Cultivation and Nitrates,” read by Mr. J. B. Fuller, C.I.E., before the Agricultural Society of England, and embodied in the 3rd Series, Vol. VII., Part 4, 1896. Egypt possesses, in the vicinity of Luxor, natural beds of nitrates of unlimited extent, which come down to the river’s edge. These nitrate beds have been used from time immemorial, but were brought to the notice of the general public by Mr. Floyer. They contain only about 6 per cent. of pure nitrates, but as they are on the edge of the Nile, in a perfectly cloudless and very dry country, it might be possible, with the aid of the plentiful supply of water always at hand to profitably extract pure nitrates. The demand for nitrates is without limit in the Nile Valley, as Nile water, though rich in everything else, is exceedingly poor in nitrates.

The perennial canals and collateral works have cost £4·50 per acre, and the maintenance charges are £·10 per acre. The perennially irrigated lands are let at £5 to £8 per acre per annum as against £3 to £5 for the basins lands.

30. Flood protection in Egypt.

—The Nile during high floods is considerably above the level of the country, which is protected by embankments stretching from Assouân to the sea. In Upper Egypt, a very high flood is one metre above the country; in Middle Egypt it is 2 metres, and the same on the Rosetta branch of the Nile. On the Damietta branch it is 3·50 metres in places.