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WEW ACID GAS, 



An Aeeounl of a New GaSy with a Reply to Mr. Murray's 

 last Observations on Oxlmuriatic Gas. By Mr, JaHN 

 Davy. 



To MR. NICHOLSON. 



SIR, 



Mr Dairy's XIlBOUT six months since Mr. Murray undertook t» 

 ^^toZbv M' oppose ^^'■' Davy's theory respecting oxlmuriatic gas, and 

 Murray. to defend the old hypothesis, iu which this substance is 



considered as a compound of oxigen and an unknown basis 

 called muriatic acid, and common muriatic acid gas as a 

 compound of the same basis and water. 

 His experi- Independent of his general reasoning, the only argument* 



faems, advanced by tnis gentleman in support of his opinions vjrere 



derived from his own experiments, undertaken expressly 

 for the purpose. His first attempt to discover oxigen in 

 oxlmuriatic gas was by trying the action of this substance 

 on carbonic oxide ; and he concluded, that it did not exert 

 any when the mixture of the two gasses, previously dried, 

 was exposed to the influence of light. He then endeavoure4 

 to prove, that the addition of hidrogen to the mixture in- 

 duced action, and the formation of carbonic acid gas. He 

 also attempted to show that oxlmuriatic gas, if supplied ia 

 sufficient quantity, is capable of affording oxigen to sulphur 

 kn sulphuretted hidrogen, and of converting it into sulphur 

 reous or suiphuric acid. 

 Q'QjeceJoriS. To account for these supposed changes in consequence of 



the presence of hidrogen, he was obliged to imagine, in op- 

 position to all experimental evidences, that the composition 

 of muriatic acid gas is indefinite: that the unknown basi^ 

 con^biues with diifeierit proportions of water, but always 

 retains the aupearance and the gaseous state of common 

 muriatic acid gas, hitherto the only subject of experijiient. 



Having given this outline of Mr. Murray's mode of de- 

 fence of the old hypothesis, I shall briefly state the facts \ 

 ventured to oppose to it, 

 Wa;cf .M>8:.tnt It was first ahown^ that muriatic acid gas, and the sul- 

 phuretted 



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