IRRIGATION OF CROPS 



and so continuing till it is time to resume the round. 

 The proper intervals, in a time of drought, may 

 be taken to be about one week, on the average, 

 though this must vary with the crop, the soil, the 

 temperature, and the judgment of the cultivator. 

 The same variation may be expected in estimating 

 the amount of water necessary for one thorough 

 irrigation. No general estimate on these points 

 can be given that will be at all satisfactory, except 

 merely as a rough rule for planning the scale of the 

 works. In establishing such a system, no great 

 nicety of calculation is likely to be of any value. 

 The data already given, and the practical examples 

 which have been cited, will enable any one, making 

 due allowance for variations of circumstances, 

 to arrive at a conclusion near enough for his 

 purposes. 



[35] 



