Comhinations of different Metals and Cldonne^ ^c. 5 



tity of oxvgen in some metallic oxides. The general ana- 

 locv of ciefinite proportions ted me to both these under- 

 takuigj. This analogy, it will be perceived, I have con- 

 stantly kept in view, and have had recourse to, both for 

 detecting inaccuracies in my own experiments, and in 

 considering the results of the experiments of others. 



As ihe nomenclature connected with the old hypothesis, 

 respecting bxymuriaiic acid, is inconsistent with the new 

 views of this subi^tance, [ shall venture to call the com- 

 pounds of the metals and chlorine to he treated of, by the 

 names which my brother has proposed for them. 



1. On the Comhinations of Chlorina and Copper, ^c. 



There are two distinct combinations of chlorine and cop- 

 per, both of which mav be directly made by the combustion 

 of this metal in chlorine gas. When the gas was admitted 

 into, an exhausted retort containing copper filings, the 

 filings became ignited, a fixed fusible substance quickly 

 formed, and the interior of the retort soon became lined 

 with a fine yellowish brown sublimate. The former sub- 

 stance evidently contains least chlorine ; for when it was 

 heated alone in chlorine gas, it absorbed an additional por- 

 tion, and was converted into the latter. Hence the fixed 

 comfiound may, in conformity with the principles of Sir 

 Humphry Davy's nomenclature, be called cuprane, and the 

 yellow sublimate, cupranea. 



Cuprane mav be procured in several other ways. It 

 mav be obtained by heating together copper filings and 

 corrosive sublimate ; and it was thus first discovered by 

 Boyle, who called it resin of copper, from its similitude to 

 common resin. Two parts of corrosive sublimate, and one 

 part of copper filings, I have found the best proportions of 

 the materials. 



It mav be obtained bv boiling copper filings in muriatic 

 acid, or by exposnig slips of c('pper partially immersed in 

 this acid to the atmosphere. In the last instaiice, I have 

 foinul the changes connected with the formation of cuprane 

 rather cumplicated ; the cojjper exposed receives oxvcen 

 from the atmosphfre, and acid from the ascending muriatic 

 acid fLimcf, and is thus converted into a green insoluble 

 sail ; and this absorbing more muriatic acid, s-lowly passes 

 into the deliquescent mu'iat, which flowing into the mu- 

 riatic acid is cliangcd by the action of the unmersed cop- 

 per into cuprane. 



M. Proust, the first modern chemist who examined cu- 

 prane, and who is commonly considered as the first dis- 

 A 3 coverer 



