352 Miscellanies. 
The sulphurets tend also to decompose it. In powder or in solu- 
tion the alkaline sulphurets produce a disengagement of gas and 
a precipitation of sulphur. 
Sugar, starch, fibrine, and muscular flesh, act upon it slowly, but 
animal matters more sensibly than vegetable. 
Ether dissolves the liquid, immediately, but soon deposits needle- 
form crystals which appear to be pure sulphur. . 
In all the cases above recited, there will be perceived, in the ac- 
tion of other bodies, a remarkable analogy with the binoxide of hy- 
drogen of M. Thenard. 
Other compounds will probably in time be discovered, having 
analogous properties, and thus establish a new branch of chemistry. 
Rev. Encyc. Mov. 1831. 
5. Chemical Agency of Light.—A series of experiments on the 
relations of oxalic acid to metallic oxides, conducted by J. W. Dobe- 
reiner, induces him to draw the inference that the chemical influence 
of light is very. rarely analogous to that of heat, and that it is sue ge- 
neris ;—that the one determines a contraction, the other an expan- 
sion, of the matter, and that the reductive action of light is a con- 
sequence of the contractive force of that agent, while the effect by 
which heat promotes combustion and almost every kind of chemical 
penetration, is the result of the dilatation of the matter occasioned 
by it. The cause of this opposition of effect is unknown, and we 
can scarcely hope to discover it, when we reflect with what facility 
light is transformed into heat, and vice versa.— Bib. Univ. Nov. 1831. 
6. Splendid combustion of hydrogen gas under strong compress- 
zon; by Prof. Dobereiner. (Jahrbuch fiir Chemie und Physik.)— 
Hydrogen gas, under common pressure, burns, both in atmospher- 
ic air and oxygen gas, with a feeble and scarcely visible lame. The 
flame becomes more brilliant only when brought into contact with 
amore solid substance, susceptible of becoming red hot, such as 
platinum foil, oxide of zinc, lime, magnesia, &c. 
Davy infers from phenomena of this sort, that the brilliancy of all 
flame is owing to the presence of a solid incandescent substance, 
which is formed or disengaged during combustion, and that a gase- 
ous substance never can be heated so as to emit a vivid light. 
_+ The cause of these opposite phenomena, may be found in the dif- 
ferent modes by which heat acts on various substances ; elastic flu- 
