Combinations of different Metals and Chlorine . 171 
absorbing more muriatic acid, slowly passes into the deliques- 
cent muriat, which flowing into the muriatic acid is changed 
by the action of the immersed copper into cuprane. 
M. Proust, the first modern chemist who examined cu- 
prane, and who is commonly considered as the first discoverer 
of this compound, found it produced by the action of muriat 
of tin on muriat of copper ; he named it white muriat of copper, 
and ascertained that a similar substance results from the de- 
composition of the common deliquescent muriat by heat. 
Cuprane, by whatever means prepared, possesses the same 
properties. It is fusible at a heat just below that of redness, 
and in a close vessel, or a vessel with a very small orifice, it 
is not decomposed or sublimed by a strong red heat; but if 
air, on the contrary, is freely admitted, it is dissipated in dense 
white fumes. It is insoluble in water. It effervesces in nitric 
acid. It silently dissolves in muriatic acid, from which it may 
be separated by the addition of water, which precipitates it 
unaltered ; and it is decomposed by a solution of potash ; or by 
heating it with the fused hydrated alkali : when it affords the 
orange oxide of copper. Its colour, transparency, and texture 
appear alone to vary. It is generally opaque, of a dark brown 
colour, and of a confused hackly texture ; but I have obtained 
it by cooling it slowly after it has been strongly heated, of a 
light yellow colour, semi-transparent, and crystallized, appa« 
rently in small plates. 
Cupranea is only very slowly formed by heating cuprane 
in chlorine gas. The best mode that I have found, of pro- 
curing it, is by slowly evaporating to dryness, at a tempera- 
ture not much above 400 of Fahrenheit, the deliquescent 
muriat of copper. Thus made, it has the same appearance 
Z 2 
