FULMINATING MERCURY. 187 



alcohol and nitric acid as might (by predisposing affinity) favour as 

 well as attract an acid combination of the hydrogen of the one, and 

 the oxygen of the other. The pure red oxyd of mercury appeared 

 not unfit for this purpose j it was therefore intermixed with alcohol, 

 and upon both nitric acid was alfused. The acid did not act upon 

 the alcohol so immediately as when these fluids are alone mixed to- 

 gether, but first gradually dissolved the oxyde : however, after 

 some minutes had elapsed, a smell of ether was perceptible, and a 

 white dense smoke, much resembling that from the liquor fumans 

 of Libavius, was emitted with ebullition. The mixture then throve 

 down a dark-coloured precipitate, which by degrees became nearly 

 white. This precipitate -I separated by filtration ; and observing it 

 to be crystallised in smaller acicular crystals, of a saline taste, and 

 also finding a part of the mercury volatilized in the white fumes, I 

 must acknowledge, I was not altogether \\ithouthopes that muriatic 

 acid had been formed, and united to the mercurial oxide ; 1 there, 

 fore, for obvious reasons, poured sulphuric acid upon the dried 

 crystalline mass, when a violent effervescence ensued, and, to my 

 great astonishment, an explosion took place. The singularity of 

 this explosion induced me to repeat the process several times ; and 

 finding that I always obtained the same kind of powder, I pre- 

 pared a quantity of it, and was led to make the series of expert, 

 ments which I shall have the honour to relate in this paper. 



" I first attempted to make the mercurial powder fulminate by 

 concussion ; and for that purpose laid about a grain of it upon a 

 cold anvil, and struck it with a hammer, likewise cold. It deto. 

 nated slightly, not being, as I suppose, struck with a flat blow ; for 

 upon using three or four grains, a very stunning disagreeable noise 

 was produced, and the faces both of the hammer and the anvil were 

 much indented. 



" Half a grain, or a grain, if quite dry, is as much as ought to be 

 used on such an occasion. 



u The shock of an electrical battery, sent through five or six 

 grains of the powder, produces a very similar effect. It seems, 

 indeed, that a strong electrical shock generally acts on fulminating 

 substances like the blow of a hammer. Messrs. Fourcroy and 

 Vauquelin found this to be the case, with all their mixtures of oxy. 

 muriate of potass. 



" To ascertain at what temperature the mercurial powder ex. 

 plodes, two or three grains of it were floated on oil, in a capsule of 



