1813.] Imperial Institute of France, 391 



the principal agent takes only a certain quantity of oxygen from 

 the acid, though it reduces it to a state in which its action on 

 reactives differs little from that of common muriatic acid. Hence 

 he concludes that this state is the first degree of oxidation of the 

 muriatic base. Decomposing the oxymuriatic acid completely, 

 by means of ammonia, he found 23-64 per cent, of oxygen in- 

 stead of 9*41 5 which was the result of his first analysis. 



In one of his preceding memoirs M. Berthollet had stated 

 facts from which it was easy to conclude that carbureted hydro- 

 gen gases existed; but he had neglected to draw that conclusion. 

 The analysis of olefiant gas by M. de Saussure has set that truth 

 in a clear light, by showing that this gas contains no oxygen, 

 and that it is a real carbureted hydrogen gas, composed of 86 

 parts of carbon and 14 of hydrogen. 



Mr. Dalton, in treating of this subject in his New System of 

 Chemistry, has endeavoured to prove that hydrogen and carbon 

 combine only in two proportions. The one gives us olefiant gas, 

 the other the gas of marshes. He considers the gases named by 

 Berthollet oxycarhureted hydrogen, as mixtures of carbureted 

 hydrogen, carbonic oxide, and hydrogen. According to Dalton, 

 olefiant gas, when exposed to heat, or to the action of electri- 

 city, passes to the state of the gas of marshes, by depositing one 

 half of its carbon; and the gas of marshes, when exposed to the 

 same action, is entirely decomposed. If we obtain a peculiar 

 gas before that decomposition is complete, this gas is a mixture 

 of hydrogen and the gas of marshes. 



M. Berthollet has repeated these experiments with electri- 

 city; but they have not led him to the results announced by 

 Dalton. A part only of the gas was decomposed, and that 

 which remained undecomposed resisted the most violent action 

 of electricity. M. Berthollet concludes, likewise, contrary to 

 the opinion of Dalton, that the small quantity of azote which is 

 found in the gas of marshes is a constituent part of that gas ; for 

 this gas, collected at very different periods, always contained the 

 same proportion of azote. 



M. Berthollet, having exposed olefiant gas to the action of 

 heat, did not obtain the results announced by Dalton. Far from 

 finding only two compounds between hydrogen and carbon, he 

 found, on the contrary, that they are capable of uniting in 

 indefinite proportions, which vary according to the degree of 

 heat which they have experienced. 



M. Berthollet likewise exposed oxycarhureted hydrogen gas 

 to the action of heat, and obtained results analagous to those just 

 mentioned. It deposited carbon, and its specific gravity dimi- 

 nished. Carbonic oxide gas was exposed in a red-hot tube to the 

 action of hydrogen, without undergoing decomposition. Tiiis is 



