tricity, 



EXPANSION OF CARBONATED HIDROGEN. J35 



On the Expanfwn of carbonated Hidrogen Gas. 



This fact was firft obferved by Dr. Aufen. On pafling the Dr. Auftin fiift 

 electric fpark through a quantity of carbonated hidrogen gas, ^^^-^ 

 he found that the gas was permanently dilated to more than 1S expanded to 

 twice its original bulk. He concluded that this remarkable doubl2 b y elcc- 

 expanfion could only be owing to the evolution of hidrogen 

 gas. Upon burning the air thus expanded in oxigen gas, he 

 found that it required more oxigen for its combuftion than an 

 equal quantity of carbonated hidrogen gas, which had not 

 been expanded by the electric fpark. An addition therefore 

 had been made to the combujiible matter ; for the quantity of oxi- 

 gen neceflary to complete the combuftion of any body, is al- 

 ways proportional to the quantity of that body. He con- His theory that 

 eluded from thefe experiments, that he had decompofed the carbon }' hidro " 



r ill gen and azote. 



carbon which had been diflblved in the hidrogen, and that 



carbon was compofed of hidrogen and azote, foine of which 



was always found in the veflel after the combuftion. 



If Dr. Auftin had more attentively conftdered the circum- Objcftlons. 



ilances of thefe experiments, he would probably been pre- "^^"not* 



vented from drawing this conclufion. The quantity of comb uf- more combufti- 



tible matter had been increafed. Now, if the expanfion of the ble than carbo " : 

 9 . ill and tlie P rodu & 



carbonated hidrogen gas was owing merely to the decompo-j s no t mere 



fition of carbon, no fuch increafe ought to have taken place, ™ ztc \ and azote » 



, . -,-!/• but alio carbonic 



but rather the contrary ; for the carbon, which was ltielt a ac ;d gas . 



combuftible fubftance, was refolved into two ingredients, hi- 

 drogen and azote, only the firft of which burnt on the addi- 

 tion of oxigen, and the application of heat. And befules, if 

 the carbon had been refolved into hidrogen and azote, the 

 product of the combuftion could only have been a greater quan- 

 tity of water, with a refiduum of azote; for the hidrogen 

 evolved by the dilatation of the carbonated hidrogen gas, com- 

 bining with the additional oxigen, muft have formed an addi- 

 tional quantity of water. But it is a fact, which the Doctor 

 does not feem to have attended to, that befides water, carbo- 

 nic acid gas is produced from the combuftion of the expanded 

 carbonated hidrogen. Whence, then, comes the carbonic 

 acid gas ? 



Air. Henry *, who repeated Dr. Auftin's experiments with Mr. Henry 

 great accuracy, found that he was correct with regard to the ^waiLa ii & 

 * Philof. Tranfaft. 1797. 



4 increafe 



