144 ACIDIFIABLE COMBUSTIBLES. 



does not exceed this quantity by so much as 

 Toofeooth part. 

 composi- The S p ec ifi c gravity of carbonic acid gas being 



tion of car- J 



bonicacid. thus ascertained with rigid accuracy, we have 

 only to subtraction! it the specific gravity of 

 oxygen gas, to know the weight of carbon united 

 in it, with a volume of oxygen gas. 



Sp. gr. of carbonic acid gas 1-5277 

 oxygen gas 1*1111 



0-4166 = carbon 

 Thus we learn, that this acid is composed of 



Oxygen . I'll 11 or 2 

 Carbon . 0-4166 or 0-75 



Atomic 2 denotes 2 atoms of oxygen ; and O75 must 



weight of , . Ji=) 



carbon. be the atomic weight of carbon. Thus it ap- 

 pears, that carbonic acid is a compound of 2 

 atoms of oxygen, and 1 atom of carbon.* 



The carbon in this gas is evidently in the state 

 of vapour. If we consider the gas as a com- 



* If the specific gravities of oxygen gas and carbonic acid gas were 

 1*1026 and 1-5240, as stated by Berzelius and Dulong, an atom of car- 

 bon would be 0-76438, a number considerably higher than the one pitched 

 upon by Berzelius; for, 1-5240 1-1026 = 0-4214 = the quantity of 

 carbon in a volume of carbonic acid ; so that carbonic acid would be a 

 compound of 



Oxygen 1-1026 or 2 



Carbon . 0-4214 or 0-76438 



It is obvious from this, that these specific gravities cannot be accurate. 



