" Farmyard Manure. 



293 



best secured by preventing the escape of liquids. With dung of 

 a very dry character (horse manure), especially in a covered 

 dungstead, it may be desirable to add water, but only if there 

 is no chance of superfluous moisture escaping by drainage. 



If manure is stored in a compact, deep dungstead, with a 

 properly constructed floor, and if care be taken to prevent its 

 getting more water than falls directly on it in the form of 

 rain or snow, there is no need to cover it in. Loss by excessive 

 washing can be better prevented by other means than by erecting 

 a roof over the mass. It is obvious that the advantages of a 

 covered dung-heap will be greatest in a district of heavy rain- 

 fall, but in any case it is doubtful if it will pay to provide a roof 

 for the dungstead unless it can be also used as a cattle-shed. 



Many farmers prevent loss due to escaping liquids by leading 

 these directly on to the land, or by conducting them to a tank 

 which is periodically emptied into a liquid manure cart and 

 distributed over the land. If the character and lie of the fields 

 suit such methods of treatment, they are in every way com- 

 mendable, but local circumstances often make it difficult or 

 impossible to carry them out. 



Over-heating and excessive loss of weight are obviated by 

 compression and saturation, simply because the dung-heap 

 under these conditions contains comparatively little air, and air 

 is a necessity of fermentation and decomposition. 



To bring raw manure into a rotten condition, farmers often 

 turn it over once or twice, the result of which is that air per- 

 meates the whole mass, and great heat is developed, with 

 corresponding loss of weight. No doubt there are circumstances 

 where such treatment is expedient ; but, considering the cost of 

 labour and the loss of organic matter, and, to some extent, of 

 nitrogen, it is probable that the process is often performed when 

 it would be better avoided. The familiar example of the slow 

 combustion of a " backed " or " banked " fire of coals is strictly 

 comparable with what takes place in a well-packed mass of dung, 

 while in both cases rapid combustion, with concurrent disappear- 

 ance of solid material, will follow vigorous stirring. 



Equality of Composition throughout the whole mass should 

 be secured as far as possible, or otherwise the best results both 

 in the heap and on the crop will not be secured. The dung from 



