60 BOARD OF AGRICULTURE. 



proprietor in taking the necessary means to save it. This 

 substance contains nitrogen in large proportion. An animal 

 takes a considerable amount of nitrogen in its food daily, and 

 unless growing rapidly, or giving milk, must necessarily elimi- 

 nate it in some other way. Every movement of the body, in 

 any of its parts, involves a waste of the materials making up 

 its structure, and this waste or effete material is taken up by 

 the circulation and excreted from the system, while its place is 

 supplied by a new portion, derived from the food. The greater 

 part of this excretion takes place through the kidneys, though 

 the solid manure also contains it. Then if the animal is 

 eventually consumed on the farm, it is evident that there need 

 be butvery little loss of nitrogen ; and even if the animal is 

 sold, the amount of nitrogen in its composition at any one time 

 bears but an extremely small proportion to the total amount 

 that has been consumed and excreted by it during life. 



What is true of nitrogen, is true to a greater or less extent of 

 all the salts and inorganic matters generally, found in the food 

 and in the body of the animal. If all of them could be 

 carefully treasured and returned to the land, a farm would 

 necessarily and constantly improve in its producing capacity. 

 We have seen, however, from the nature of the case, that this is 

 not always practicable, nor does nature demand it, even if it 

 could be done. The soil itself contains an inexhaustible store of 

 inorganic matters, which are constantly becoming available in 

 quantities sufficient to produce moderate crops. To exceed 

 that amount we must add to the soil some of those substances 

 which we have shown to exist in manure, and if we fail to save 

 them we are under the necessity of purchasing from foreign 

 sources. It is quite possible to return to the soil the whole of 

 the woody fibre, inasmuch as it is all contained in the solid 

 evacuation of the animal ; and we can give back all the other 

 elements of the plant, except those portions carried off in the 

 milk, or eventually in the bodies of the animals themselves, by 

 saving and applying all the urine. We venture the assertion, 

 that a farmer, saving all the manure, licjuid and solid, made by 

 his stock, and judiciously applying it, can raise constantly 

 increasing crops up to the capacity of his lands, without the 

 purchase of extraneous manures. But if ho is selling con- 

 stantly, or from time to time, constituents that ho does not 



