1822.] Composition of the Alkaline Sulphurets. 353 
in solution is a sulphuret of a higher degree, but the composition 
is difficult to determine, because part of the hyposulphite remains 
in solution. To avoid this inconvenience, I boiled sulphuret of cal 
cium (C a S*) (prepared with pure lime heated ina current of sul- 
phuretted hydrogen gas) with sulphur in, excess, until it was sa- 
turated ; I decomposed the solution by muriatic acid, separated 
and weighed the sulphur, and converted the muriate of lime 
into sulphate. I obtained 1-682 gramme of sulphur, and 1-815 
gramme of gypsum. These make 8 atoms; for an atom of 
gypsum (equal to 171438) is to 8 atoms of sulphur, represented 
by 1601-9 as 1-815 is to 1-690. Adding 2 atoms of sulphur, which 
disappeared in the form of hydrogen gas, we find 10 atoms, and 
the hepar of lime at a maximum is also composed of Ca H* $". 
In general only two determinate compounds can be prepared 
in the moist way, one with 10 atoms, and the other with 4. The 
latter is obtained with potassium and sodium, by exposing the 
neutral sulphuret to the air, until half its hydrogen is oxidated 
and converted into water, by means of which K H* §+4 is formed. 
This compound may be obtained with lime and strontian, as 
MM. Herschel and Gay-Lussac have proved, by boiling the 
earth with sulphur, and suffering the solution to cool; this com- 
pound then crystallizes. The intermediate degrees are obtainable 
only by mixture in proportions determined by calculation. 
‘The nature of these solutions may be considered in two modes, 
and it is at present impossible to decide which is the correct 
one: first, either water is decomposed by the sulphur when the 
combustible body is dissolved by the alkali, or by the base of 
the alkali when the metallic sulphuret is treated with water ; 
secondly, or the metallic sulphuret dissolves in water without 
being altered, and the sulphuretted hydrogen, which the acids 
evolve from the solutions, are formed only at the instant in 
which the potassium is oxidated by means of the acid. 
{n the first hypothesis, the hepar is a compound of potash and 
sulphuretted hydrogen ; but then this latter body cannot be con- 
sidered as the only one of its kind. There must be as many 
degrees of sulphuration for hydrogen as there are for potassium ; 
that is to say, if we except the odd numbers 7 and 9 from the pre- 
ceding experiments, there must exist compounds of two atoms 
of hydrogen with one, two, three, four, and five atoms of sul- 
phur, each forming peculiar salts. Itis evident that the deno- 
minations of hydrosulphates and hypohydrosulphates are no longer 
proper. It would be more correct to call these different com- 
pounds hydrosulphureis, hydrobisulphurets, hydrotri, &c. 
I made several vain attempts to obtain the compounds of 
eke in ‘an isolated state; they separated always into sul- 
phuretted hydrogen gas and an oily compound, in the same 
manner as the peroxide of hydrogen. This compound cannot 
exist unless with an acid, and even then it exists but a few 
New Series, vou. tv, Qa 
