376 SELECTIONS FROM ADDRESSES. 



these gases ; they are the best perfumery the farmer can 

 have." But how can we save them ? There are many ways. 

 If a weak sohition of the oil of vitriol be sprinkled upon any 

 surface, or mixed with any liquid that is yielding this gas, the 

 peculiar smell will no longer be perceived. Without the aid 

 of sealed jars and close stoppers, simply by the laws of chem- 

 ical affinity, it lies a prisoner, as much at your service as the 

 ox that is tied in the stall. It is no longer volatile — it is fixed. 

 But the oil of vitriol is a dangerous compound, and should be 

 employed by none but the chemist. A very convenient sub- 

 stitute for this is found in the article copperas, which is sold in 

 the shops, and which is composed partly of oil of vitriol. A solu- 

 tion of this is perfectly harmless, and is effective for sprinkling the 

 places I have alluded to. A still cheaper and more convenient, 

 though not so effective substance, is plaster of Paris, which 

 also contains vitriol. If this be scattered freely upon any 

 place, which is evolving ammonia, the smell will at once be 

 destroyed ; and from this we learn that it forms a chemical 

 union with the gas dindi fixes it. So also pulverized charcoal is 

 quite efficient ; it forms no chemical union ; but one known 

 property of charcoal is that it will absorb and retain large quan- 

 tities of gaseous substances, especially if it be made from hard 

 wood and be recently prepared. A mixture of equal parts of 

 plaster of Paris and pulverized charcoal, will be very effective, 

 for retaining this airy compound I speak of. And the intelli- 

 gent farmer will not forget that fresh earth of every kind, and 

 most of ail, peat, have the power of absorbing and holding large 

 quantities of aeriform substances. With all these methods of 

 prevention then, if farmers allow the idle winds to steal odors 

 from them, and rifle their manures of their richest ingredients, 

 they are quite inexcusable. 



And what shall I say of those piles of fertilizing substances, 

 that lie around our stable doors, and on the bottom of our cow- 

 yards, exposed to sun, wind, and rain? Does not every 

 farmer know that not any vegetable or animal product can be 

 exposed to the air, and moisture, and a temperature above sixty 

 degrees, without at once beginning to ferment ; and that during 

 this process vast quantities of various gases roll away, like 



