Chemical Science. 155 
Researches were then made into the nature of this acid: the 
term fulminate, has been applied to the salts containing it. Mu- 
-Tiate of potash added to fulminate of potash produced no precipi- 
tate of chloride of silver; but muriatic acid decomposed the salt, 
and chloride of silver, muriate of ammonia, hydrocyanie acid and 
earbonie acid, resulted. Fulminate of potash does not preci- 
pitate persulphate of iron, nor does the addition of muriatic acid 
form a prussiate of iron, , Metallic copper precipitates all the silver 
from fulminate of potash, and a plate of zine indicates the copper 
present; but excess of potash does not separate the copper, nor 
‘does the fluid become blue by adding ammonia, though when the 
solution is decomposed by npuriatie acid, the copper is easily found 
by those tests. Chromates, prussiates, and carbonates, do not 
precipitate the silver from alkaline fulminates; these properties 
point out a strong analogy between this acid and the metalliferous 
cyanic acids. 
The fulminating acid boiled with oxide ofsilver, gave fulminating 
silver; boiled with oxide of mercury, it produced a compound in 
small brilliant plates. 
Conceiving from analogy that the acid of fulminating mercury 
differed from that of fulminating silver in the substitution of the 
former metal for the latter, experiments were made to ascertain 
this point; crystals of fulminating mercury boiled with potash, 
deposited oxide of mercury, and the fluid, when precipitated by 
nitric acid, gave.a white precipitate, which, when dry, detonated 
strongly by percussion; with baryta, strontia, and lime, similar 
compounds to those formed by fulminating silver, were produced. 
The separation of the acid from fulminating mercury does not al- 
ways succeed. In only two operations out of eight was the acid 
obtained in yellow detonating crystals. 
A quantity of fulminating silver was put with metallic mercury 
into water and boiled ; after some time the liquid became turbid, it 
was filtered, and furnished crystals exactly the same as those pro- 
duced by the acid of fulminating silver and the oxide of mercury. 
Boiling another portion for a much longer time, the precipitate 
deepened in colour, and when no more was formed, the whole was 
filtered and crystallized. The crystals were very fine, and pure 
fulminating mercury; and an amalgam of mercury and silver re- 
mained. ‘Ihe reverse operation was performed of preparing ful- 
minating silver from fulminating mereury; the latter was boiled 
with silver which had been precipitated from the nitrate by copper, 
and to which a quantity of platina filings had been added; by the 
galvanic action of the two metals the mercury was precipitated, 
‘and the silver dissolved. The experiment requires rapid manipu- 
Jation and simple decantation, otherwise the crystals will always 
‘contain mercury. 
Fulminating silver was boiled with copper; the silver precipitated, 
