154 Miscellaneous Intelligence. 
the deposit augmented. The vessel should not be cooled hastily 
in this process, as great loss of the compound is occasioned. 
Thus prepared, the fulminating silver appears in white silky 
acicular crystals, possessing the well known detonating properties, 
perfectly soluble in 36 parts of boiling water, and re-crystallizing as 
the solution cools. It has a metallic taste, stains the skin, if 
exposed to air becomes first red, then black, and to test papers 
appears as a neutral salt. 
Fulminating mercury was prepared according to Howard’s process: 
100 grains of mercury being dissolved in half an ounce of concen- 
trated nitric acid, and two ounces of alcohol added. Heat is then to 
be applied, as in the former case. At firsta little nitrate of mercury 
is deposited, but is soon redissolved, and then ona sudden the liquor 
becomes grey from the reduction of part of the oxide of mercury, 
and the liberation of a dense vapour, occasioned by the volatiliza- 
tion of a portion of mercury with the ether that rises. After some 
time the liquid becomes yellow, and dendritical crystals appear, 
which augment on cooling until nearly a quarter of an inch in 
length. ‘hey are greyish-white, harsh to the touch, and heavy, 
but when purified by being dissolved and crystallized two or three 
times, appeared as perfectly white brilliant silky crystals, having a 
mild metallic taste, and detonating violently by a blow. ‘They 
are pure fulminating mercury. 
On adding lime-water to fulminating silver the latter dissolved, 
leaving a little black oxide of silver; when a few drops of nitric 
acid were added to the clear solution a white precipitate fell, which 
detonated like the original compound. It now dissolved without 
any residue in lime-water, and was precipitated again by acid, as 
before, without any indication of decomposition. 
Substituting potash for lime-water, and boiling, exactly the same 
effects took place. The fulminating silver combined also in the 
same manner with magnesia, baryta, strontia, soda, and ammonia, 
and with all of them presented the same phenomena, except that 
ammonia did not cause the separation of oxide of silver. The 
quantity of oxide separated by the alkaline bases from 100 of ful- 
minating silver was 31.25, 
Thus it appears that fulminating silver perfectly resembles a 
compound salt; its acid combines with the alkalies, &c., and its 
base, the oxide of silver, separates; and in confirmation of this view 
of its nature it was found that compounds of the acid, and all other 
bases, might be obtained perfectly definite and crystallized, and 
possessing strong detonating properties. 
A quantity of fulminating silver was decomposed by lime, the 
liquid filtered, concentratel, and carefully precipitated by nitric 
acid, excess of the latter being avoided. The new acid, when well 
washed, appeared as a white powder, very soluble in boiling 
water, reddening litmus paper, and crystallizing on cooling. 
