“ 
62 
Mr, Davy means to apply himself.to 
the solution of these important questions 5 
but as the enquiry now stands, he thinks 
it-evident that he is correct with respect 
to the composition and decomposition 
of ammonia; and that MM. Gay 
Lussac’s and Thenard’s idea of the de- 
composition of the potassium, and their 
theory of its being compounded of hydro- 
gen and potash, are unfounded: fora 
considerable part of the potassium is 
recovered unaltered; and in the entire 
decompositign of the fusible substance, 
there is cnly a small excess of hydrogen 
above that existing in the ammonia acted 
upon. 
The phenomena of the process prove 
the same thing. After the first slight 
effervescence, owing to the water ab. 
sorbed by the potash, formed upon the 
potassium during its exposure to the air, 
the operation proceeds with the greatest- 
tranquillity. No elastic fluid is given off 
from the petassium. The crystallized 
substance formed in the first part of the 
process, may be considered as a comhi- 
nation of anmonium and potassium; for 
it emits a smell] of ammonia when ex- 
posed toeair; and is lighter than petas- 
sium. Mr. D. first thought, that a solid 
compound of hydrogen and potassium 
might be generated in the first part of the 
operation; but his experiments do not 
favour the opinion. Potassium Is very 
soluble in hydregen; but, under com- 
mon circumstances, hydrogen does not 
seem absorbable by potassium. 
In the examination of sulphur, Mr. 
Davy made use of that which had been 
recently sublimed, and the power applied 
to it was that of a battery of 500 double 
plates of six inches bighly charged. The 
action was most intense, the beat strong, 
and the light extremely brilliant: the sul- 
phur soon entered into ebullition, elastic 
matter was formed in great quantities, 
and the sulphur, from being of a pvre 
vellow, became of a deep red brown tint. 
The gas proved to be sulphuretted hydro- 
gen. In other experiments, upon the 
union ef sulphur and potassium, it was 
proved, that these bodies act-upon each 
other with great energy; and that sul- 
phuretted hydroden is evolved in the 
process, with intense light and heat. In 
heating potassium in contact with com= 
pound inflammable substances, as rosin, 
wax, camphor, and the fixed oils, it was 
found that a violent inflammation was 
occasioned; that hydrocarbonate, was 
evaived; and that when the compound 
Proceedings of Learned Societies. 
[May 1, 
was not in great excess, a substance was. 
formed, spontaneously inflammable at 
common temperatures, the combustible. 
materials of which were charcoal and 
potassium, Here was a strong analogy © 
between the action of these bodies and 
sulphur on potassium. Their physical 
properties likewise resemble those of 
sulphur; for they agree in being non-con- 
ductcrs, whether fluid or solid; in being 
transparent when fluid, and semi trans- 
parent when solid, and highly refractive. 
Their affections by electricity are hke= .’ - 
wise similar to those of sulphur; for the 
oily bodies give out hydrocarbonate by 
the agency of the voltaic spark, and be- 
come brown, as if from the deposition of 
carbonaceous matter. But the resinous 
and oily substances are compounds of a 
sinall quantity of hydrogen and oxygen 
with a large quantity of a carbonaceous’ 
basis. The existence of hydrogen in 
sulphur, is fully proved; and the sub- 
stance which can be produced from it in 
such quantities, cannot be considered as 
an accidental ingredient. 
The reddening of the litmus paper by — 
sulphur that has been acted on by voltaig 
electricity, might be ascribed to its con- 
taining some of the sulphuretted hydro- 
gen formed in ,the process ; but even the 
production of this gas is au evidence of 
the existence of oxygen in sulphur. 
Mr. D. heated four grains of potassiam, 
in a retort of the capacity of twenty cu- 
bical inches; it had-been filled with sul- 
phuretted hydrogen, dried by means of — 
muriate of lime: as soon as the potas~° 
sium fused, white fumes were copiously 
emitted, and the potassium took fire, and 
burnt wich a most brilliant flame. A 
small quantity of the residual gas only 
was abserbed. Tie non-absorbable gas 
was hydrogen, holding a minute quantity ~ 
of sulphur in solution. A yellow subli- 
mate lined the upper part of the retort, 
which proved to be sulphur. The solid 
matter formed was red at the surface, 
like sulphuret of potash; but in the 
interior it was dark grey, like sulphuret — 
of potassium. ‘The piece of the retort 
containing it, was introduced into a jar - 
inverted over mercury, and acted upon 
by a small quantity of dense muriatie 
acid, diluted with an equal weight of 
water; when there were disengag- 
ed two cubical inches and a quarter 
of gas, which was sulphuretted hydro 
gen. ; 
This, and other experiments, concur in 
proving the existence of a principle in 
: sul phuretted 
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