60 



Irrigation and Drainage 



two cylinders filled with soil, having a depth of 42 inches and a 

 diameter of 18 inches. These four stalks of corn, as they were 

 coming into tassel and their ears were beginning to form, used 

 during 13 days 150.6 pounds of water, or at the mean rate daily 

 of 2.896 pounds for each stalk. Had an acre of ground been 

 planted to corn in rows 3 feet 8 inches each way and four stalks 

 in a hill, then, with an average consumption of water at the ob- 



Fig. 10. Total root of four stalks of maize, and of oats, clover and barley. 

 (From "The Soil.") 



served rate given above, there would have been withdrawn from 

 that acre an amount of water, during those 13 days, equal to 244 

 tons, or 2.42 acre-inches ; and when it is observed that this water 

 was withdrawn from a soil so dry that no amount of pressure 

 could express a drop of water from it, it is not strange that such 

 a mass of roots as those shown in Fig. 10 should be required to 

 carry away from the soil the water absorbed by the root -hairs as 



