CHAPTER VIII 



SOILS 



"Population must increase rapidly, more rapidly than in former 

 times, and ere long the most valuable of all arts will be the art of 

 deriving a comfortable subsistence from the smallest area of soil." 



Abraham Lincoln 



"It is not the land itself that constitutes the farmer's wealth, but 

 it is in the constituents of the soil which serve for the nutrition 

 of plants that this wealth directly consists." 



Liebig 



SOIL PHYSICS 



The soil a great natural resource. The few feet of soil 

 covering the surface of the earth form the most important 

 natural resource we have. The inscription carved over the 

 entrance to the Agricultural Building of the University of 

 Illinois "The wealth of Illinois is in her soil, and her strength 

 lies in its intelligent development" is true for all the states 

 of the Union. It is well, therefore, that we study the origin, 

 nature, composition, and function of this valuable resource, to 

 the end that it may be wisely used and permanently conserved 

 for all the future generations. The careless observer is likely 

 to think of the soil as merely dirt, and the unskilled farmer 

 who dislikes his occupation often thinks of the soil only as 

 a prison floor to which, perhaps, he is bound by chains of 



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