26 SOUKCES OF LOSS IN FERMENTATION. 



when somewhat dried, ifc has a tendency to form hard 

 masses, which, when buried in the soil, may resist 

 decomposition for a very long period. The cause of 

 this is due to the presence of a considerable amount 

 of mucilaginous and resinous matter in the solid ex- 

 creta, which prevent the entrance of moisture and air 

 into the centre of the mass. This tendency of cow- 

 manure to resist decomposition will be greatly lessened 

 in the case of the excrements of a cow richly fed. 



The risks of loss of volatile ammonia are, there- 

 fore, in its case not so great as we have seen them 

 to be in the case of the " hot " horse-dung. Not- 

 withstanding this fact, much of what has been said 

 on the use of preservatives for horse-manure may be 

 also applied to the cow-dung. This is owing to the 

 fact that the dung is allowed to accumulate in the 

 court for some time. The amount of straw it is advis- 

 able to use as litter varies, as has been said, from 6 to 

 10 Ib. per day. The best method of calculating this 

 amount, according to Dr Heiden, is by taking one- 

 third of the total weight of the dry substance of the 

 food. The above authority also recommends that the 

 straw is best applied in blocks of about one foot in 

 length; and this for the following reasons: 



1. The strewing of it is more convenient. 



2. The absorption of the fluid portion is more 

 complete. 



3. The cleaning out of the manure from the byre 

 is easier. 



