Highest Probable Duty of Water 215 



sure to result. In India and Siam writers on this sub- 

 ject state that from 43 to 45 acres is the usual duty 

 of a second-foot. The mean value for good, thorough 

 watering appears to be 43.2 acres per second -foot, or 

 a depth of water aggregating, for the year, between. 19 

 and 20 feet on the level. 



If reference is again made to the table on page 

 198, it will be seen that this duty of water is much 

 smaller than was realized in the experiments cited. 

 According to the results there given, one second -foot 

 should be able to serve the number of acres stated in 

 the table below: 



The highest probable dutfr of water for different crops expressed in acres per 

 second-foot for different yields per acre 



