18 THE CULTURE OF FARM CROPS. 



and the luxuriance of the vegetation in its vicinity; caused 

 doubtless by its absorption of ammonia. It will absorb 

 ninety times its bulk of this gas, thirty-five times its bulk 

 of carbonic acid, and nine times its bulk of oxygen. Char- 

 coal made from the hard and dense woods exerts this 

 absorbing power .in the greatest degree; having as 

 much as one hundred square feet of surface in its ex- 

 ceedingly fine pores, in every cubic inch. This power to 

 condense gases gives it a very great importance in agri- 

 culture in various ways. It absorbs noxious gases and of- 

 fensive odors, and when crushed so as to expose its greatest 

 absorbing surface will filter water and purify it from foul 

 matter, and restore tainted meat to its former sweetness. 

 It will absorb the deadly carbonic acid which accumulates 

 in wells and pits, and thus remove the danger of loss of 

 life in entering such places. It will purify and remove 

 the dark color from cider, syrups, wines and vinegars, and 

 is thus used to a large extent. 



Charcoal is thus a powerful disinfectant as well as a de- 

 odorizer; for by condensing in its pores noxious vapors 

 and gases, it removes poisonous substances from the air 

 and avoids the danger of fatal diseases. It however does 

 not act as an antiseptic and prevent decomposition, but 

 hastens it, by absorbing oxygen, which is the most active 

 agent of decomposition; and which rapidly destroys or- 

 ganic matter; but while thus accelerating the decay of 

 substances which are brought into contact with it, it pre- 

 vents all offensive results by continually seizing upon these 

 products and causing their immediate oxidation. This 

 process goes on continually and thus a small quantity of 

 powdered charcoal may have a surprisingly disproportion- 

 ate effect. It is turned into valuable use in this way by 

 surgeons for poultices to corrode and decompose sloughing 

 and gangrenous flesh, in malignant sores and in serious 

 wounds. It changes ammonia into nitric acid and thus 

 serves a most useful purpose as an ingredient of manure 

 heaps and composts; preventing the loss of valuable am- 

 monia and changing it into the stable forms of nitric acid 



