COMMON SALT. OBJECT OF MANURES. 107 



asparagus, but it kills nearly all the weeds ; and as weeds 

 are commonly nothing but valuable plants out of place, 

 it must be used with discretion, or it may do more harm 

 than good. 



Applied in small quantities, it has the effect of render 

 ing grass and clover more pleasant to animals, and, in a 

 small proportion, it is of the greatest value to all cultivated 

 crops. It is also a valuable addition to the farmyard 

 and to the compost heap. Salt which has been used in 

 curing fish or meats is much cheaper and far better than 

 pure salt. 



359. The object of manures is to give to the soil what 

 ever is wholly or partly wanting to it, whether of a com 

 bustible or an incombustible nature. The use of organic 

 manures is to furnish the soil with humus, geine or 

 mould, which shall serve as a reservoir, to hold in readi 

 ness, for the use of plants, all the kinds of food necessary 

 to their growth. And the use of humus is to furnish and 

 keep a ready supply of carbonic acid, ammonia and water, 

 which three are the last result of the decomposition of 

 vegetable substances. 



360. Such being the object, organic manures should be 

 employed in a condition favorable to decomposition, either 

 in a fermented state or, better still, ready to enter into 

 fermentation. Manures which should refuse to decom 

 pose would be of no use. But the decomposition must 

 not be too far advanced. Ammonia is very volatile, as 

 its common name indicates, and may readily escape into 

 the air and be lost. The penetrating, characteristic odor 

 of ammonia is perceived in stables, near manure heaps, 

 and wherever else nitrogenous substances, that is, vege 

 table and animal substances containing nitrogen, are in a 

 state of decay. Every one who has had occasion to use 



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