IRRIGATION WATER IN THE SOIL 113 
these experiments shows the increase in each foot 
about eighteen hours after a small and also a larger 
irrigation : — 
PERCENTAGE OF WATER IN SOIL 
Water Time oF (Foor Srcrions) 
APPLIED 
encase SAMPLING . 
ver- 
1 2 3 4 5 6 7 8 age 
2.5 Before 
irrigation . | 9.57|10.55}11.78/12.92/11.92/11.41/11.75/11.49] 11.43 
After 
irrigation . |19.24/13.70]13.1 |13.84|12.66/12.72/12.31]12.70| 13.67 
Increase . | 9.67] 3.15] 1.39] 0.87] 0.74] 0.31] 0.56] 1.21] 2.24 
7.5 Before : 
irrigation . |10.62/12.44/14.44}15.11|14.20/13.40]/13.13)13.27| 13.33 
After 
irrigation . |23.83/21.83/20.05| 17.40) 15.87! 14.66)14.21/14.15] 17.75 
Increase . {13.21} 9.39] 5.61) 2.29] 1.67) 1.26) 1.08) 0.88) 4.42 
It will be seen that in the soil that was already 
well filled with water, the addition of water was felt 
distinctly to the full depth of 8 feet. Moreover, 
it was observed in these experiments that even very 
small rains caused moisture changes to considerable 
depths a few hours after the rain was over. For 
instance, 0.14 of an inch of rainfall was felt to a 
depth of 2 feet within 3 hours; 0.93 of an inch 
was felt to a depth of 3 feet within the same 
period. 
