3. =Information Concerning Canals.=--Nearly all canal irrigation is done by “flow,” the water running from the water-courses onto the fields, but a small proportion is done by “lift.” This is done in the case of high pieces of land, the lifting being usually done by pumps or, in the east, by bullocks or by manual labour. Irrigation generally consists in giving the land a succession of waterings, one previous to ploughing and others after the crop is sown, each watering being of quite moderate depth. On inundation canals in India the waterings for the summer crop are thus effected but for the winter crop the land is deeply soaked during the flood season and is afterwards ploughed and sown. In Upper Egypt this system is emphasised, the water flowing into vast basins, formed by dykes, where it stands for some time and, after depositing its silt, is drained off. Until recent times the whole of the irrigation of Egypt was basin irrigation. In Lower Egypt the construction of the Nile barrage led to the introduction of canals which take off at a proper level and their working is not restricted to the period when the river is in flood. In Upper Egypt most of the irrigation is still basin irrigation but the canals taking off above the Assiut barrage form a notable exception. By means of the Assouan dam which crosses the Nile, the water during the latter part of the flood season and after the floods are over, i.e. from November to March, is ponded up and a vast reservoir formed and the impounded water is let down the river in May and June. In some of the older irrigation canals of India the velocity was too high and the channels have since had to be remodelled and the crests of weirs raised or new weirs built. The more recent canals are free from grave defects of this kind but every canal undergoes changes of some kind and finality has never yet been quite attained. On some Indian irrigation canals made about 30 years ago, great sums of money were wasted in making the canals navigable. There is nothing like enough navigation to pay for the extra cost. The idea has now been quite given up except as regards timber rafting from upstream. This requires no curtailment of the velocity in the channels. The requirements of the irrigation and navigation were always in conflict. The mere fact that branches have to be worked in turns is enough to prevent navigation succeeding. In India the water used for irrigation is paid for, not according to the volume used but according to the area irrigated. The volume used in any particular watercourse is not known. The areas sown are measured. Certain kinds of crops use up more water than others and the charges are fixed accordingly.