CARBON. 145 



pound of 1 volume oxygen gas and 1 volume 

 carbon vapour, condensed into one volume, it is 

 obvious that the specific gravity of carbon va- 

 pour is O4166. As is the case with hydrogen, 

 azotic, and chlorine gases, a volume of it is equi- 

 valent to an atom. 



II. Carbon enters into another gaseous com- C 



. , , , . . tion of car- 



bmation with oxygen, namely, the gas distm- bonk- oxide 

 guished by the name of carbonic oxide. The as 

 atomic weight of this gas is not of so much im- 

 portance as that of carbonic acid, because we 

 do not know any compounds of which it consti- 

 tutes a part; but it will be worth while to de- 

 termine it, because the knowledge of it will serve 

 still farther to elucidate and confirm the preced- 

 ing conclusions respecting the atomic weight of 

 carbon. 



Carbonic oxide was discovered by Dr. Priestley, 

 but its nature was first ascertained by Mr. Cruik- 

 shanks. M. M. Clement and Desormes made a 

 set of experiments on it nearly at the same time, 

 or very soon after Cruikshanks, and came to the 

 same conclusion with him : namely, that it is 

 a compound of oxygen and carbon without any 

 hydrogen. 



I have never succeeded in obtaining it abso- 

 lutely free from all admixture of carburetted hy- 

 drogen gas. Its specific grayity according to my 

 trials is O9700. But, owing to the carburetted 

 hydrogen which it contained, this result is too 



VOL. I. K 



