REPORT ON CHEMISTRY. 
455 
phuretted hydrosulphurets, and is understood by Berzelius to 
consist of 
Four atoms sulphur. , 5 § 
One atom sulphuretted hydrogen. _J~ 
From the analysis of the octohaedral soda salt, Dr. Thom¬ 
son states its composition to be two atoms sulphur + one atom 
hydrogen, and therefore, in his System, he retains the name 
Z?i-sulphuret *. 
M. Thenardf has published some observations on this sin¬ 
gular substance, the object of which is to point out its strong 
analogy to the deutoxide of hydrogen, in its action upon the 
skin and other animal textures, in bleaching and destroying 
them ; its power of discharging vegetable colours; its action 
upon the metals, and the more easily reduced metallic oxides 
when in the state of fine powder; in the facility with which it 
is decomposed, and the influence of a few drops of very diluted 
acid in retarding decomposition for a considerable time. 
Finely divided charcoal, several of the metals in the state of 
powder, as platina, gold, iridium, many oxides, the peroxide 
of manganese, and all the earthy bases, are acted upon by it 
with brisk effervescence; with potash and soda it is so violent 
as to resemble ebullition. The oxides of silver and gold are in¬ 
stantly reduced with incandescence. 
M. Thenard prepares it by boiling quicklime in water, with 
an excess of sulphur, and pouring the filtered solution by de¬ 
grees into muriatic acid, diluted with twice its weight of water, 
and shaking the mixture. Prepared in this way, the compo¬ 
sition and density must vary, as it is always contaminated by a 
mixture of sulphur or sulphuretted hydrogen. He obtained it 
of the specific gravity 1*769, and two different specimens gave 
him, on analysis, eight atoms of sulphur to one of hydrogen, 
and six atoms of sulphur + one of hydrogen. The process of 
Berzelius, who directs a solution of the crystallized potash salt 
to be employed, would probably give more uniform results. 
The sulphurets decompose this compound, disengaging sul¬ 
phuretted hydrogen gas, and causing a deposit of sulphur;— 
hence the reason why it is not obtained when an acid is poured 
into a solution of any of its salts. The excess of sulphuret 
present decomposes the bisulphuret of hydrogen, as it is formed, 
causing sulphur to precipitate and gaseous sulphuretted hydro¬ 
gen to be given off. 
Nitrogen .—One of the easiest methods of preparing nitrogen 
Chemistry of Inorganic Bodies, i. p. 278. 
t Annahs de Chimie, xlviii. p. 79. 
