THE BRAIN OF THE EARTH 



close-meshed silken cloth; while, in the other 

 case, the moisture would run down between 

 the particles like a stream of water pumped 

 through a coarse sieve, leaving nothing behind 

 it. The rich soil would conserve the moisture, 

 the poor soil would waste it. 



The water of the most refreshing rain will 

 rapidly disappear in a coarse, loose soil like the 

 one photographed. And, even where the soil 

 has considerable food supplies, the water would 

 be of little value, swiftly disappearing and 

 leaving nothing stored up for a day of drought. 

 Putting it somewhat contradictorily, the coarse 

 soil puts by nothing for a rainy day. 



And water is all-essential for these soils. 

 Investigation has shown that, to produce an 

 average acre of clover or potatoes, at least four 

 hundred tons of water are needed for the sea- 

 son ; for an acre of peas, wheat or oats, three 

 hundred and seventy-five tons; for an acre of 

 corn, three hundred tons, while, to bring an 

 acre of sunflowers to maturity, at least six 

 thousand tons of water are needed, twelve 

 millions of pounds of moisture. 



One English investigator holds that at least 

 six hundred and fifteen tons of water is taken 



15 



