4 M, Berzelius wpm the Alkaline Sulphurets^ and on 
M. Berzelius thinks also, that the maximum of sulphuration 
of potassium is not well determined, and that KS^° may, pro- 
bably, be the true protosulphuret ; but the experiments which 
he has yet made on this point only give vague results. He has 
often, for example, produced a hepar of a more lively colour 
than the ordinary kind, and which dissolves in water, leaving a 
residue of sulphur in powder. But when M. Berzelius melted 
the hepar with a great excess of sulphur at a gentle heat, and 
left it afterwards to cool so slowly, that the sulphur could sepa- 
rate from the hepar by means of its inferior specific gravity, the 
superior stratum was only pure sulphur, and the inferior one 
dissolved in water without a residue. A solution of in 
water, which was made to boil with sulphur, dissolved a little of 
it ; but the sulphur precipitates itself by cooling. A solution 
of in alcohol, dissolves by digestion much of the sulphur, 
a part of which separates in cooling ; but it is difficult from 
this, to distinguish between a solution of sulphur in alcohol, and 
an affinity of potassium for a new dose of sulphur, aided by 
the presence of alcohol. 
M. Berzelius is of opinion, that in every case we may consi- 
der the sulphurets of potassium which contain S, 4, 6, 8 and 10 
atoms of sulphur, as well established. It is evident, that the 
sulphur is found in the very simple ratio of 1, 2, 8, 4 and 5. 
M. Berzelius next examines the preparation of hepar in the 
humid way. Having melted the hydrate of potash with a 
gentle heat, he added to it small portions of sulphur, which dis- 
solved with strong effervescence, and produced a flocculent mat- 
ter which swam upon the melted sulphur. The effervescence 
arose from the disengagement of the vapours of water. The 
ffocculent matter separated from the sulphuret, was the hypo- 
sulphite of potash. When the potash employed was in excess, 
the sulphuret assumed in cooling, the reddish pale colour of cin- 
nabar. This is the colour of the protosulphuret of potassium ; 
and this experiment proves, that it is the potash, and not the 
water, which was decomposed by the sulphur ; for had it been 
otherwise, it would have formed a colourless hydro-sulphate of 
potash. Whatever excess we take of potash, it does not form at 
this temperature either the sulphurous or the sulphuric acid. 
