AMERICAN INSTITUTE. 397 



a slow burning, and serves the same purpose of throwing off in 

 gaseous form the principal part of the substance, and leaves as a 

 residue those mineral constituents which in ordinary combustion 

 remain as ashes. After such liberation these ashes become sub- 

 servient to the necessities of growth. It is highly improbable 

 that in the soil any organic matter is completely evaporated; a 

 portion of its carbon is sure to remain in the form of pure (or 

 nearly pure) charcoal. After it once assumes this form it is im- 

 possible, under natural circumstances, for a cubic inch of charcoal 

 placed in the soil may remain for centuries unaltered in quan- 

 tity, and resisting all of the destructive influences of air, water 

 and vegetation. The existence of this form of carbon in the soil 

 is not without its use, as we shall see in the consideration of the 

 next proposition concerning it. 



Second: The absorbent power of charcoal which it possesses in 

 its various forms of muck, &c., constitutes by far its greatest 

 agricultural value. I buried a dead mule last summer in a pile 

 of muck only a few inches deep, but it absorbed all the efiluvia, 

 so that none escaped into the air. Since that time the work of 

 purification has been completed, and that stubborn piece of flesh 

 has assumed an airy form, and has taken its temporary abode in 

 the pores of that serviceable muck-heap, where it awaits future 

 commands. But seriously, Mr. Chairman, since this power of 

 muck has been doubted, I have deemed it proper to make some 

 further investigations among the best chemical authorities, and I 

 have obtained the following results : 



1. Boxwood charcoal, perfectly dry, absorbed thirty-five vol- 

 umes of carbonic acid gas, and when moistened, it absorbed but 

 fifteen volumes. In the first case the absorption required twenty- 

 four hours; in the second, fourteen days. 



2. Bottles filled with tobacco-smoke, or asafcetida, may be 

 rendered inodorous in from one to three hours by the insertion 

 of dry charcoal. 



3. Stagnant waters, emitting offensive odors, are rendered pure 

 by the action of charcoal . 



4. Liebig says : " Some gases are absorbed and condensed 

 within the pores of the charcoal into a space several hundred 

 times smaller than they before occupied, and there is now no 

 doubt that they become fluid, or assume a solid state." I think, 

 Sir, that any man, no matter how unlearned he may be, will have 

 sufficient common sense to understand, from his own experience, 

 and from the foregoing testimony, the following points, namely : 



