128 
METALLIC OXIDES. 
Oxides of tin. dry, and the oxide by the nitric acid remained, I then dissolved 
pure tin in a mixture of the nitric and muriatic acids, but with 
a greater proportion of the former. It produced during the time 
it was dissolved, a white insoluble mass, which, after being 
filtered on a paper, was dissolved by pure water, and was the 
muriate of the oxide at a maximum. 
The solution of tin distilled in a retort, at first produced water 
mixed with a little nitric acid, afterwards the spirit of libavius 
which became more and more concentrated, and at the same 
time disengaged a small quantity of oxy muriatic gas. It 
remained at last in the retort in a white powder, which at a red 
heat did not appear to alter. A small quantity of this powder 
being taken out of the retort and mixed with water, was entirely 
dissolved by it. The solution was coagulated by ebullition, and 
precipitated by an addition of muriatic acid, consequently it 
was the muriate of the oxide at a maximum, which remained 
in a fixed state, at a temperature greatly surpassing that required 
to volatilize the liquor of libavius. The portion of muriate 
which remained in the retort exposed to ignition, slowly pro- 
duced the spirit of libavius, and disengaged at the same time 
oxymuridic gas; but even after I had exposed in a platina 
crucible to the highest possible temperature, muriatic acid 
remained, which I separated by means of the alkali. 
This experiment proves, that when tin is dissolved by nitro- 
muriatic acid, it forms itself into two distinct muriates, of 
which one is deposited in the solution when it begins to con- 
tain a considerable quantity ; and when the liquor is distilled 
the spirit of libavius is obtained in the receiver, while the 
muriate of the oxide at a maximum remains in the retort. 
Tlfis latter is, with some difficulty, decomposed by heat, and 
produces oxymuriatic gas and the spirit of libavius. 
It would be, undoubtedly, a very interesting thing to decide 
what different influences these two oxides of tin have on 
colours, for which the nitromuriatic solution of tin is often 
employed as a mordant. 
As it is proved by these experiments that the oxide in the 
spirit of libavius is not the same as that formed by the nitric 
acid, and as this latter ought to contain more oxigen than the 
former, it is evident, that it should contain an intermediate 
quantity between the stanneous oxide and the oxide produced 
by 
