Combinations of different Mefals and Chlorine, ^c. 9 



the atmosphere slips of copper partially immersed in mu- 

 riatic acd; and it is also produced by the exposure of 

 cupranc to the atmosphere. Its produclion in the last in- 

 stance is accompanied with that of the deliquescent muriat; 

 and the f)rnja'ion of both seems to be owing to the ab- 

 sorption of wa er and oxygen; for cuprane, I have found, 

 though apparently not in the least acted on by dry oxygen 

 gas, is quickiy changed when moistened with water and 

 confined in a jar of this gas, and there is a rapid absorption 

 of oxvgen *. 



f have not examined all the specimens obtained bv these 

 different methods minutely, though sufficiently, I conceive, 

 to ascertain their identity, and their similarity to the native 

 compound. The colour of all of them is grtenish white, 

 like that of the native, in a finely divided s'a:e. When 

 heated, they all afford water, oxygen gas, and a mixture 

 of cuprane and brown oxide of copper. 



I have analysed only the .snbmuriat, precipitated from a 

 solution of nuiriut of copper by a weak solution of potash. 



Fifty grains of this, well washed and dried, boiled in a 

 solution of potash, afforded 36"3 grains of dried brown 

 oxide of copper. 



And 20 grains dissolved in nitric acid, and precipita ed 

 by nilrat of silver, afforded 12'75 grains of dried horn sil- 

 ver. These results differ so little from those obtained with 

 the native, as fairly to permit the conclusion, that the com. 

 position of the artificial and native submuriat of copper is 

 the same. 



2. On the Comlinations of Tin end Chlorine, &^c. 



Tin, like copper, is capable of combininsr with two dif- 

 ft:rent proportions of chlorine. The liquor of Libavius, 

 one of the toinbinations, is directly formed by the com- 

 bustion of the metal in chlorine gas; and the other, I find, 

 may be produced by heating together an amalgam of tin 

 and calomel. Thus obtained, it is siniilar to that which 

 niay be procured by evaporating to dryness the nuiriat 

 containing the gray oxide of tin, and fusing the residue in 

 a close vessel. Both are of a <rr.iv colour, and (da resinous 

 lustre and fracture, and both inflame, like tin itself, when 

 heated in clilorine gas, and are converted into tin?' liquor 

 of Libavius by the absorption of a fresh poriion^of chlorine. 



• I liave liecn informed that lulimuriat of copper is sonietinies found !o 

 t^e iiei;;lilj(Jiirh<)od of volcanoes, p.irticul.irly in that of Vesuvius. Djr 

 means of the above facts, it is evident that iis pruJuctiun might be ac- 

 couiutd fur in such skuatioDi. 



Hence, 



