28 AGRICULTURE. [ctt. 



able products ; and, secondly, to produce manures 

 for the land. 



49. There are two ways in which this vegetable 

 matter is added to the land as manure. When sheep 

 and other stock are fed with it upon the land, the 

 excrement of these animals conveys to the soil those 

 portions of their food which have not been added 

 to their bodies, or used in the support of their warmth. 

 This excrement returns to the soil very valuable 

 inorganic and organic matter which the plant 

 had originally drawn from the soil, and so far 

 as these matters are restored to the land, so far its 

 exhaustion is checked. In the table already given 

 (41) you have seen how largely crops of turnips 

 which are usually fed on the land draw upon the 

 soil in their growth ; if therefore you return this matter 

 to the soil, from a chemical point of view, you 

 render it almost as capable of producing another 

 growth as it had previously been. 



50. In the form of farm -yard manure another 

 large portion of this vegetable matter finds its way 

 back to the land. The course of operation is not 

 as simple in this case, for whilst in the former instance 

 the manure became quickly intermingled with the 

 soil, in this case it has to be preserved until it can be 

 carted to the land. In the necessary treatment which 

 this manure has to undergo there is a great liability 

 to loss. 



51. The production and management of farm-yard 

 manure are based upon certain principles which are 

 easily understood, and with these you will readily be- 

 come familiar. This manure consists of the straw, or 

 other litter or bedding for the stock, and of the excre- 

 ments the stock may produce. It is well known that 

 the excrement of the different kinds of stock kept 

 upon a farm varies very considerably. That from 

 horses ferments rapidly and gets very hot, that from 

 cattle is slow to ferment and is consequently a cool 



