J24 
METALLIC OXIDES. 
Oxides of tin. its weight of pure sulphur pulverized. I exposed this to a 
suddenly elevated temperature, in a glass retort, in order to 
melt it, and I kept it in a state of fusion, until the sulphur was 
volatilised. The upper part of the retort contained a small 
quantity of mosaic gold. The sulphuret of tin had a metallic 
lustre, of the colour of lead, and the broken part was crystal- 
line, and very brilliant. When dissolved in concentrated 
muriatic acid, it gave out sulphurated hydrogen gas, which, 
being passed through a ley of caustic kali, was entirely ab- 
sorbed by it. Hence it follows, that the sulphur of the sul- 
phuret of tin, is, to the oxigen of the stanneous oxide, as the 
sulphur in sulphurated hydrogen gas, is to the oxygen in the 
water. Another part of the sulphuret of tin was treated in 
a glass phial, with fuming nitric acid, until it was entirely 
decomposed ; the contents of the phial was then carefully 
poured into a crucible of platina, dried, and at last heated to 
a red heat, until all the acid was expelled. 1 00 parts of the 
sulphuret, produced in this manner, 99*5 parts of the white 
oxide of tin. From this, it follows, that the oxigen in the 
white oxide, is nearly equal in quantity to the sulphur of the 
sulphuret, consequently, the white oxide produced by the nitric 
acid, contains twice as much oxigen as the slibious oxide. Ac- 
cording to the experiments I have already published, the white 
oxide of tin is composed of 100 parts of metal, and 27‘2 p. 
of oxigen; the stanneous oxide is therefore composed of: 
Tin , 88*028 100 0 
Oxigen 1 1‘972 13 6 
White Oxide of Tin. 
It is generally admitted, or at least, as far as I know, never 
disputed, that the oxide of tin, which is found in the volatile 
combination, known by the name of spirit of libavius, is the 
same as that which is formed when the tin is burned in the air, 
or oxided by nitric acid. We find it, nevertheless, sometimes 
observed by chemists, that the latter is insoluble in the acids, 
when, on the contrary, the first ought to be soluble in them, 
as it exists in the liquor of libavius. The cause to which that 
is attributed, has generally been, that the oxide produced by the 
combustion, or by the nitric acid, was to that in the spirit of 
libavius, as the ignited zircone to that contained in the salts. 
The 
