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SOILS AND MANUEES 



ANALYSIS OF SOILS (DRY FINE EARTH). 



of phosphoric acid in any of the examples quoted is 0'38 

 per cent. ; the calcareous soil contains only O'Ol per cent. 

 It is obvious, therefore, that some of the most important 

 ingredients of the soil are normally present in very small 

 proportion. It must be remembered, however, that a small 

 percentage corresponds to a large quantity of the substance 

 in the total mass of soil, and that the quantities required 



