l± COMBINATIONS OF OXIMURIATIC ACID AND METALS. 



TIence 100 of cupranea, omitting the very slight loss, 

 appear to consist of 

 Component 53 chlorine 



parts. 47 copper 



Two other 

 mviriates. 



100 

 The deliquescent muriate, and the native muriate of cop- 

 per of Peru, belong to a class of compounds apparently dis- 

 tinct from the preceding combinations of copper and chlo- 

 rine. 

 The deliques- rpjjg (Jeliquescent salt is well understood ; and its compo* 

 ""' ' sition may be inferred, independent of its water, from that 



of cupranea. 



The naxive muriate is less known, I shall therefore relate 

 the experiments I have made on this interesting mineral, 

 the njf.ve mu- The specimen I have examined is part of a -very fine one, 

 riate of Peru, presented to Sir Humphry Davy by William Jacob, Esq. 

 M. P., and deposited in the Museum of the Royal Institu- 

 tion. It consists of muriate and carbonate of copper, of red 

 oxide of iron, and of green coloured quartz. The muriate 

 is partly crystallized ; the crystals, from the trials I have 

 made of them, appeared to be pure, and they were, on that 

 account, made the subject of my experiments. 

 Its pro^-erties* The crystallized muriate dissolves entirely and without 

 effervescence, in all the acids in which I have tried it, and 

 the deliquescent muriate of copper is in each instance form- 

 ed, and a combination of brown oxide of copper with the acid 

 employed. 



Heated slowly in a bent luted glass tube, connected with 

 mercury, the native muriate affords water and oxigen gas, 

 and the residue is an agglutinated brownish mass, which dis- 

 solves in muriatic acid, and gives a greenish precipitate wirh 

 potash, and is apparently a mixture of brown oxide of cop- 

 per and cu prune. When the heat is raised rapidly to red- 

 ness, the water expelled is impregnated with muriatic acid, 

 arid muriate of copper. I have obtained from 25 grains of 

 the n>ineral, heated to redness till gas ceased to be produced, 

 just two cubic inches of oxigen. This expulsion of oxigen 

 seems to be owing to the action of chlorine on the brown 

 oxid^ to forui cuprane ; and there is, 1 have ascertained, a 



siinilar 



