APPENDIX 



drawn is inclosed by low embankments called checks. These 

 checks are multiplied until the whole field is covered. The 

 water is then drawn into the highest basin, permitted to 

 stand until the ground is thoroughly soaked, and then drawn 

 off by a small gate into the next basin. This process is re- 

 peated until the entire field is irrigated. This is the system 

 practised on the Nile, where the basins sometimes cover sev- 

 eral square miles each, while in the West they are often no 

 more than four hundred feet square. There is both a crude 

 and a skilful way to accomplish the operation of flooding, and 

 there is a wide difference in the results obtained by the two 

 methods. The Indian and Mexican irrigators, in their igno- 

 rance and laziness, seldom attempt to grade the surface of the 

 ground. They permit water to remain in stagnant pools 

 where there are depressions, while high places stand out as 

 dusty islands for generations. All except very sandy soils 

 bake in the hot sunshine after being flooded, and the crude 

 way to remedy the matter is to turn on more water. Water 

 in excess is an injury, and both the soil and the crops re- 

 sent this method of treatment. 



The skilful irrigator grades the soil to an even slope of 

 about one inch to every hundred inches, filling depressions 

 and levelling high places. He "rushes" the water over the 

 plot as rapidly as possible, and when the ground has dried 

 sufficiently cultivates the soil thoroughly, thus allowing the 

 air to penetrate it. The best irrigators have abandoned the 

 check system altogether, and have invented better methods 

 of flooding the crops. Cereals and grasses must always be 

 irrigated by flooding, but the check system seems likely to 

 remain only in the land of Spanish speech and tradition, where 

 it was born. In Colorado wheat and grass are generally irri- 

 gated by a system of shallow plough furrows run diagonally 

 across a field. The water is turned from these upon the 

 ground, and permitted to spread out into a hundred small 

 rills, following the contour of the land. Some farmers bc- 



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