FERMENTATION OF EXCREMENT. 273 



Lime, ...... 4.6 



Magnesia, . . . . . . 3.8 



Oxide of iron, ..... 1.2 



Oxide of manganese, . . . . 2. 1 



Alkaline chlorides, . . . . 0.3 



Phosphoric acid, . . . . . 10.5 



Sulphuric acid, . . . . . 1.9 



Ash of cow-dung from the same : 



Organic matter, ..... 90.2 



Ash, ...... 9.8 



100.0 



Sand and silica, . . . . . 63.7 



Lime, ...... 7.6 



Magnesia, . . . . . . 3.6 



Oxide of iron, . . . . . 8.5 



Phosphoric acid, ..... 12.5 



Sulphuric acid, . . . . . 1.8 



Horse-dung in the short period of twenty-four hours heats 

 and begins to suffer loss by fermentation. If left in a heap 

 for two or three weeks, hardly seven-tenths of its original 

 weight will remain. Hence, when to be used for manure, it 

 should be removed early from the stable, and mixed as soon as 

 possible with some other material, such as those just mentioned 

 in the case of nightsoil. 



Cow-dung ferments more slowly than that of the horse and 

 the sheep. In fermenting it does not heat much, and gives off 

 little if any unpleasant odour. It thence acts more slowly, 

 though for a longer period, when applied to the soil. The 

 slower fermentation of cow-dung arises partly from the less 

 proportion of substances containing nitrogen, partly from the 

 less perfect mastication of the food than in man, the horse, or 

 the sheep. Cow-dung, nevertheless, undergoes a sensible loss 

 if exposed uncovered to the open air. 



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