THE FERMENTATIONS OF MANURE. 71 



all of that in the liquid manure. From manure heaped upon soft 

 ground, large amounts of this are completely lost by draining away 

 or soaking into the ground. If the manure is left exposed to rains 

 this loss is greatly increased. As a result the ordinary manure heap 

 decreases very much in value during the weeks or months that it is 

 stored in the pile. This part of the loss can be entirely prevented 

 by storing the manure where the liquids will not leach into the 

 soil. 2. By fermentation. This subject requires a more extended 

 consideration. 



THE FERMENTATIONS OF MANURE. 



Destructive. The first chemical changes which go on are 

 those of general decomposition. An ammoniacal fermentation is 

 universal. The liquid manure is most rapidly decomposed by this 

 fermentation, the substance undergoing in a very few days, sometimes 

 in a few hours, a reduction into ammonia compounds, as already 

 mentioned above. This is completed before the ammoniacal fer- 

 mentation of the other nitrogen bodies has fairly begun, and suggests 

 that the proper method of handling manure will be to treat the 

 liquid manure separately from the solid portion. Eventually the 

 nitrogenous compounds in the solid manure will also undergo am- 

 moniacal fermentation. The starches, sugars, cellulose and woody 

 tissue undergo a decomposition by which CO 2 is set free and various 

 other substances are left. The fats and fatty acids are also decom- 

 posed, liberating CO 2 with other less known bodies. The decom- 

 position of the proteids liberates sulphur, commonly as H 2 S, and this 

 may unite with water to form sulphuric acid. The sulphuric acid 

 may combine with the ammonia to form ammonium sulphate, or the 

 ammonia may combine with the carbon to form carbonates. A 

 large quantity of material is lost from the manure during these 

 changes. The loss includes carbon in large amount, a matter of no 

 significance, however, as it has simply gone into the air from which 

 it can readily be reclaimed by plants. But the loss includes much 

 nitrogen, and this is a misfortune, since it is the nitrogen that the 

 farmer desires to keep. 



