PRESERVATION OF MANURE 1 59 



air in order to carry on their work. When deprived 

 of oxygen they become inactive. The anaerobic fer- 

 ments require the opposite conditions. They become 

 inactive in the presence of oxygen and can thrive only 

 when air is excluded. In the center of a well-con- 

 strncted manure pile anaerobic fermentation takes 



Fig. 26. Fermentation of Manure. 



place while on the surface aerobic fermentation is act- 

 ive. The anaerobic ferments prepare the way for the 

 action of the aerobic bodies. When aerobic fermenta- 

 tion is completed the organic matter is converted into 

 water, carbon dioxide, ammonia, and allied gases. 

 From what has been said regarding the action of these 

 two classes of ferments it is evident that anaerobic 

 fermentation is the most desirable. 



192. Water Necessary for Fermentation. — In order 

 to produce the best results in fermenting manure 

 water is necessary. If the manure becomes too dry 

 abnormal fermentation takes place. W T ater is always 

 beneficial on manure as long as leaching is prevented; 



