1822.] Composition of the Alkaline Sulphurets. 345 
and 164-24 constitute 8 atoms. As in this operation, K S$? + 
3 K S'° is at first formed, and as the atom of sulphate of potash 
is afterwards reduced to K S*, the whole ought to form K 8°; 
but what shows that it is a decided compound, and not a mere 
mixture, is that all the sulphur of the sulphuretted hydrogen 
escapes with the water; and consequently no K S’ is formed, 
as happens when the sulphate of potash only is decomposed. 
The compound becomes opaque after cooling. 
The hepar obtained in the preceding experiment was after- 
wards mixed with half its weight of sulphur, the mixture was 
distilled until sulphur ceased to come over, when sulphuretted 
hydrogen gas was passed through the apparatus. The hepar 
then weighed 1:259 gramme; that is, 100 parts of potassium 
were combined with 184°57 of sulphur, which makes exactly 
9 atoms. 
Two grammes of bicarbonate of potash decomposed by sul- 
phuretted hydrogen in a similar apparatus gave 1-49 gramme of 
a pale-yellow crystalline salt, in which 100 parts of potassium 
were combined with 91 of sulphur and of hydrogen, as we shall 
presently see. I added one gramme of sulphur, and the mass 
was again fused in a current of sulphuretted hydrogen gas, 
until the distillation of sulphur ceased. The matter then weighed 
2°2%3 grs.; thus 100 parts of potassium were combined with 
186 parts of sulphur ; which also makes 9 atoms. 
In a weighed retort 1-079 gramme of carbonate of potash was 
fused with 0°302 gr. of sulphur. Combination immediately took 
place at a temperature scarcely exceeding that requisite for the 
fusion of sulphur, and the mixture was exposed during an hour 
to the same degree of heat ; for when it was stronger, the car- 
bonic acid gas was extricated rapidly, carrying with it much 
sulphur in the state of a white vapour. The temperature was 
raised afterwards until the mass fused: when it had been tho- 
roughly liquefied, and bubbles ceased to appear, the operation 
was stopped. ‘lhe apparatus had lost 0:165 gramme in weight, 
which was carbonic acid that had escaped. This corresponds 
to 0°3535 of potash, of which one-fourth equal to 0-08838 com- 
bined with the oxygen of the remainder, and to 002933 of sul- 
phur, formed sulphate of potash, There remain then 0-302 — 
0:0293 = 0:2727 cramme of sulphur which were combined with 
0:22 gr. of potassium ; then 
D2 WO Diets LOO 61 23°99 
and 123-18 indicate 6 atoms of sulphur. 
The same experiment was once more repeated, and gave the 
same result. 1 employed more potash than the sulphur was 
capable of decomposing : thus the affinity of the carbonic acid 
for the potash prevented the combination of the sulphur with 
the potash and its base. Then, when sulphur is fused at a low 
