Farm Irrigation. 467 



inches of water, or more, are used in the majority of places in the 

 irrigated districts for the production of crops. Let us apply the 

 varying value of water as just explained, to the economical, or 

 rational, use of water. If the 30 acre-inches be spread over 6 

 acres of wheat, so that the whole area of 6 acres will be covered with 

 water to a depth of 5 inches, each acre will yield 32I bushels of 

 grain, or a total of 195 bushels. If the same amount of water be 

 spread over 4 acres, that is, to a depth of 7I inches, the total yield 

 of grain will be 165 bushels. Spread over 3 acres, to a depth of 

 10 inches, the same amount of water will yield 118 bushels. Spread 

 over 2 acres, to a depth of 15 inches, the total yield will be 95 

 bushels, and spread over i acre, to a depth of 30 inches, the yield 

 will be 42 bushels. It may thus be seen that, in the case of wheat 

 the total amount of grain produced by 30 acre-inches of water may 

 be increased from 42 bushels to 195 bushels by spreading the water 

 over more or less ground. Certainly the nearly five-fold increase 

 of grain thus made possible, will more than pay the farmer for 

 the labour of handling six acres of land instead of one ; and of 

 higher importance is the fact that, by using the water rationally, 

 the irrigated wheat area may be profitably increased four or five 

 times without building another reservoir or canal. 



These figures show how enormously a farmer can increase the 

 area of land irrigated by a given quantity of water if he understands 

 its scientific use. It is a subject worth studying, for on it depends 

 to a large extent the agricultural prosperity of the country. Farm 

 irrigation in South Africa has not received the attention it deserves, 

 and I am looking forward to the time when the Transvaal will 

 have Government experiment irrigation stations in various districts, 

 under the superintendence of expert engineers and agriculturalists. 

 They will be attended with the most valuable results. 



