140 



THE CHEMISTRY OP THE FAEM. 



MANURIAL CONSTITUENTS IN 1000 PARTS OF ORDINARY 

 FOODS. continued. 



The manure value of different food thus varies 

 extremely. One ton of decorticated cotton cake contains 

 about four times as much nitrogen as a ton of wheat, 

 barley or maize, and thirty-nine times as much as a ton 

 of mangel wurzel. 



The oil-cakes yield the richest manure, as they contain 

 the largest amount of nitrogen and phosphoric acid, with 

 a considerable amount of potash. Next to these come 

 the leguminous seeds, malt-dust, and bran. Clover hay 

 yields a rather richer manure than the cereal grains, 

 while meadow hay stands below them. The cereal grains 

 and the roots contain about the same proportion of 

 nitrogen in their dry substance; the roots, however, 

 supply much more potash. Potatos stand below roots in 



