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THE CHEMISTRY OF THE FARM. 



The relative value of the manure produced by different 

 foods is determined by the relative richness of the foods 

 in nitrogen and ash constituents, but chiefly by the amount 

 of nitrogen, this being the most costly ingredient of pur- 

 chased manure. The average amount of nitrogen, and of 

 the two most important ash constituents contained in 

 ordinary cattle foods, is shown in the following table : — 



MANURIAL CONSTITUENTS IN 1000 PARTS OF ORDINARY FOODS. 



