IRRIGATION IN EGYPT. 453 
The cultivable area of Egypt, or the space between desert and 
desert where cultivation would be possible, is now estimated 
at ten thousand square statute miles.* Much of the surface, 
though not out of the reach of irrigation, lies too high to 
be economically watered, and irrigation and cultivation are 
therefore at present confined to an area of seven thousand 
square miles, nearly the whole of which is regularly and 
constantly watered when not covered by the inundation, except 
in the short interval between the harvest and the rise of the 
waters. or nearly half of the year, then, irrigation adds seven 
thousand square miles to the humid surface of the Nile valley, 
or, in other words, more than decuples the area from which 
an appreciable quantity of moisture would otherwise be evap- 
orated; for after the Nile has retired within its banks, its 
waters by no means cover one-tenth of the space just men- 
tioned. 
The Nile receives not a single tributary in its course below 
Khartoum; there is not so much as one living spring in the 
British India at 6,000,000 acres, and add that canals now in construction will 
water as much more. The Indian irrigation canals are generally navigable, 
some of them by boats of large tonnage, and the canals return a net revenue 
of from five to twenty per cent, on their cost. 
* The area which the waters of the Nile, left to themselves, would now 
cover is greater than it would have been in ancient times, because the bed of 
the river has been elevated, and consequently the lateral spread of the inun- 
dation increased. See Smitu’s Dictionary of Geography, article ‘* Aegyptus.” 
But the industry of the Eeyptians in the days of the Pharaohs and the Ptole- 
mies carried the Nile-water to large provinces, which have now been long aban- 
doned and have relapsed into the condition of desert. ‘+ Anciently,” observes 
the writer of the article ‘‘ Eeypt” in Smith’s Dictionary of the Bible, ‘2,735 
square miles more [about 3,700 square statute miles] may have been cultivat- 
ed. In the best days of Egypt, probably all the land was cultivated that could 
be made available for agricultural purposes, and hence we may estimate the 
ancient arable area of that country at not less than 11,000 square statute 
miles, or fully double its present extent.” 
According to an article in the Bollettino della Socicta Geografica Italiana, 
vol. v., pt. iii., p. 219, the cultivated soil of Egypt in 1869 amounted to 
4,500,000 acres, and the remaining soil capable of cultivation was estimated 
at 2,000,000 acres, 
