1813 ] Chlorine, and its Compounds. 123 



water, has united to form muriates. To this conclusion it will 

 of course be objected, that these passages were written previous 

 to the adoption of the new theory. This objection will, however, 

 vanish, on considering, that it is not to the opinions, but to the 

 facts contained in the parages cited, that my reasoning has 



reference. 



By the publication of Mr. J. Davy's paper on the combinations 

 of chlorine with the metals,* I am enabled to bring this part of 

 the discussion more completely under examination than could 

 before be done; and in doing this 1 shall be as brief as the nature 

 of the reasoning employed will allow. 



The first compound noticed in this paper is cuprane ; which 

 is formed " by exposing slips of copper, partially immersed in 

 muriatic acid, to the atmosphere." Mr. J. Davy say* that in 

 this process the deliquescent muriate is formed — " which flow- 

 ing into the muriatic acid is changed by the action of the im- 

 mersed copper into cuprane." According to this view, cuprane 

 cannot contain more, but may have less chlorine than can be 

 yielded by the muriatic acid of the deliquescent muriate j yet 

 the analysis given ascribes to it a proportion of chlorine exceeding 

 by 12-18 per cent, what it can contain consistently with Che- 

 nevix's analysis of the proto-muriatc, and approaching within a 

 minute quantity to the proportion given fay Proust, f as belonging 

 to the per-muriate. 



Again, cuprane is stated to be composed of 64* of copper, 

 and 36- of chlorine. According to Chenevix, the proto-muriate 

 contains 70*25 of protoxide (of which G3-161 is copper), and 

 24*75 of muriatic acid. Now it is worthy of notice, that, on 

 the principles of the old theory, the quantity of oxygen con- 

 tained in the protoxide is capable of forming oxymuriatic gas 

 with 24-383 of muriatic acid ; so that the only difficulty in 

 reconciling these analyses is the water contained in the proto- 

 muriatc, which Mr. J. Davy seems to have laid to the account of 



the chlorine. 



From the analysis of cupranca having been performed on 

 its solution, it appears that Mr. J. Davy in fact examined 

 the deliquescent muriate, into which, he says, that it is con- 

 verted by the action of water. But the result of Mr. J. Davy's 

 analysis exceeds in the proportion of the chlorine that given by 

 Proust by 26816 per cent. How can this quantity of chlorine 

 escape from its combination when the compound is dissolved in 

 water, and again enter into union with the copper on the water 

 being separated. Another difficulty also lies against the analysis 

 Of cupranea. Mr. J. Davy says that it is composed of 47 of 

 copper and 53 of chlorine. Now 47 of copper, in passing to 



■ PU1. Tran?. ISIS, !'• IM. + Ann. de Chim. tome xxxii. 4T. 



