THE NEW EARTH 



The particles in a single cubic foot of aver- 

 age farm soil for general use, usually roundish 

 in shape, expose to the roots of plants an area 

 of surface three acres in extent. To show how 

 very small these particles are, it should be 

 noted that fully one-half of the cubic foot of 

 soil is air-space, so that if it were not for the 

 air it would contain twice as many particles. 

 If sixty thousand particles of a coarse clay soil 

 were placed side by side in a line, it would be 

 but twelve inches long, while the line itself 

 would be only the two ten-thousandths of an 

 inch in width. 



It is in the searching study of the soils of 

 the earth that such facts as these are developed, 

 interesting in a sense because of their novelty, 

 but immensely more interesting because of 

 their practical value. In some of the western 

 agricultural states, for example, hundreds of 

 farmers send samples of their soils to the 

 chemists of the agricultural colleges of the 

 states in order that they may test the soils and 

 find out whether or not the farmers are using 

 them to the best advantage. In some in- 

 stances the soils are unproductive because of 

 excess of strong alkaline matter ; or, again, the 



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