142 THE CHEMISTRY OP THE FARM. 



the losses during preparation, and the slowness of action 

 of farmyard manure, Lawes and Gilbert estimate that the 

 manure actually obtained from food has not more than 

 half the money value of the manurial constituents voided 

 by the animal, if these are reckoned at the prices given 

 for nitrogen, phosphates and potash in artificial manures. 



Animal manure is more immediately available for the 

 use of plants when applied directly to the land than 

 when previously fermented with a great bulk of litter. 

 During fermentation with litter the ammonia unites 

 with certain of the carbonaceous matters present, forming 

 compounds which are little soluble, and which decompose 

 but slowly in the soil. 



The feeding of animals on the land is a mode of 

 applying manure which has many advantages ; but the 

 distribution of the manure is in this case irregular, and if 

 carried out in autumn or winter the manure is subject to 

 loss by drainage. The most effective plan of application 

 is doubtless as liquid manure to growing crops. In 

 winter time, however, the use of litter, and the preparation 

 of farmyard manure (best under cover), becomes a 

 necessity, and is on the whole the best course to adopt. 



The treatment of farmyard manure, and its general 

 composition, have been already described on pp. 31-33. 



