220 THE CHEMISTRY OF CREATION 1 . 



her that, did not diffusive force lend wings to 

 the fragrant vapours poured out from the flowers, 

 none of these pleasures would be experienced. 

 We see, then, in this force a most powerful agent 

 of intimate, although imperceptible, intermixture 

 of the various gaseous and vaporous ingredients 

 of the atmosphere, whether regular or accidental. 

 Accurate investigations have made us ac- 

 quainted with a less expected gaseous ingre- 

 dient in the atmosphere than the last, light 

 carburetted hydrogen, or, as it is often im- 

 properly called, " coal gas." The amount of 

 this gas is not so considerable as that of the 

 former, but it is said to be very generally pre- 

 sent, in variable quantities, in the atmosphere. 

 The part it fulfils in the economy of the atmo- 

 sphere is not well defined. It does not appear 

 to undergo any great degree of increase or of 

 diminution, and we are therefore disposed to 

 believe that chemical relations between it and 

 other bodies actually exist, since it can be 

 clearly shown that large quantities of this gas 

 are continually discharged into the air. In 

 short, it is conceivable, on the supposition that 

 those analyses which state its constant presence 

 in the air are correct, that some force exists, as 

 in the case of carbonic acid, to decompose the 

 gas, and put a check to any excess in its quan- 

 tity. It arises from various sources, among 



