232 FARMYARD MANURE [chap. 



by the animal, but the greater part will have been 

 evaporated as ammonia during the making of the 

 manure and any turning it may have received, while 

 some will have been set free as nitrogen gas. At the 

 same time the more fermented the manure becomes, 

 and the shorter and more rotten its condition, the less 

 of the nitrogen will be present in soluble form, and the 

 more of it will have been reconverted into substances 

 akin to a protein. 



In making farmyard manure, the loss of valuable 

 nitrogen is therefore inevitable, but it is possible to keep 

 the loss down by taking suitable precautions. In the 

 first place, it is desirable to keep the manure as long as 

 possible under the feet of the animals. The least loss 

 occurs when the manure is made in deep boxes in which 

 the cattle are fed, and the manure is not removed until 

 it is ready to go straight out on the land. The turning 

 of the manure, which must be done when it is carted out 

 of the yard in order to form the mixen, always results in 

 loss. Of course, another source of loss in manure- 

 making arises through washing or leakage of the liquid 

 manure away. We have already stated that the most 

 valuable nitrogen compounds are those contained in the 

 liquid portions of the manure, which is also rich in 

 potash, so that if this material is allowed to drain away, 

 the solids that are left behind possess but little value. 

 The dark brown liquid which we often see oozing from 

 the dung-heap or leaking from the drains of a badly 

 kept yard constitutes one of the finest of fertilisers, and 

 in the management of a yard or cattle stalls the utmost 

 care should be taken to keep this material soaked up in 

 the litter. For this reason a partly covered yard is 

 desirable, so that too much rain is not allowed to wash 

 through the manure. On the other hand, the wholly 

 covered yard may easily let the manure get too dry, and 



