IHIUGATION AX2J UJiMSAGJ-:. 153 



judicious from an agricultural point of view to so divide 

 the basins into two that summer cultivation could be 

 confined to one half in alternate years, whilst the other 

 half could be flooded, as is now done, but in alternate 

 years. In this way all the land would have a thorough 

 renovation with rich Nile mud every second year, and the 

 noted fertility of Upper Kgypt would be maintained. 



Lower Egypt has now no basi&S, although in ancient 

 times the basin system was universal and survived in 

 certain parts till a century ago. Irrigation in Lower 

 Egypt is effected entirely by canals. In flood numerous 

 canals take water directly from the Nile, but in summer, 

 when the supply is limited, every drop of water is arrested 

 by the Barrage, 12 miles north of Cairo, and there distri- 

 buted by three great main canals to their respective circles 

 of irrigation. Each of these great canals is soon divided 

 into smaller ones, which in their turn are again subdivided 

 till there is a system resembling the distribution of blood 

 to the body, and every part of Lower Egypt, even to the 

 extremities, receives its due quota of water. For eight 

 months of the year, September to April, water is abundant, 

 but from Mav to August the scarcity necessitates strict 

 regulation bv a system of rotations according to which, 

 canals or sections of canals receive water for a certain 

 number of days and no water during so many more days. 

 The strigency of rotation varies with circumstances. It is 

 extreme when there are 6 days water and 18 days none. 

 It would be quite convenient for the cultivator to receive 

 water six days in each alternate week, leaving one day 

 each week when no water would be taken by any one, and 

 canals would fill up to the benefit of distant users. 



The perennial supply of water available in Lower Egypt 

 enables the agriculturist to sow half his land in summer 



