acid was affused. The acid did not act upon 
the alcohol so immediately as when these 
fluids are alone mixed together, but first 
gradually dissolved the oxide: 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. 
T he mixture then threw down a dark-co- 
loured precipitate, which by degrees became 
nearly white. This precipitate 1 separated 
by filtration; and observing it to be crystal- 
lized in smaller acicular crystals, of a saline 
taste, and also finding a part of the mercury 
volatilized in the white fumes, L must ac- 
knowledge I was not altogether without hopes 
that muriatic acid had been formed, and 
united to the mercurial oxide; 1 therefore, 
for obvious reasons, poured sulphuric acid 
upon the dried crystalline mass, when a vio- 
lent 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 find- 
ing that I always obtained the same kind of 
powder, 1 prepared a quantity of it, and was 
led to make the series of experiments which 
1 shall have the honour to relate in this pa- 
per. 
“ 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, like- 
wise cold, ft detonated slightly, not being, 
as I suppose, struck with a flat blow; for 
upon using three or four grains, a very stun- 
ning disagreeable noise was produced, and 
the faces both of the hammer and the anvil 
were much indented. 
“ Haifa grain, ora grain, if quite dry, is 
as much as ought to be used on such an oc- 
casion. 
“ The shock of an electrical battery, sent 
through five or six grains of the powder, pro- 
duces a very similar effect. It seems, indeed, 
that a strong electrical shock generally acts 
on fuinVrtiuting substances like the blow of a 
hammer. Messrs. Fourcroy and Vauqtielin 
found, this to be the case with all their mix- 
tures of oxy muriate of potass. 
* ( To ascertain at what temperature the 
mercurial powder explodes, two or three 
grains of it were floated on oil, in a capsule of 
leaf tin; the bulb of a Fahrenheit’s thermo- 
meter was made just to touch the surface of 
the oil, which was theu gradually heated til! 
the powder exploded, as the mercury of the 
thermometer reached the 368th degree. 
“ Desirous of comparing the strength of 
the mercurial compound with that of gun- 
powder, 1 made the following experiment in 
the presence of my friend Mr. Abernethy. 
“ Finding that the powder could be .fired 
by flint and steel, without a disagreeable 
noise, a common gunpowder proof, capable 
of containing eleven grains of fine gunpow- 
der, was filled with it, and fired in the usual 
way: the report was sharp, but not loud. 
The person who held the instrument in his 
hand felt no recoil; but the explosion laid 
open the upper part of the barrel, nearly 
from the touch-hole to the muzzle, and struck 
off the hand of the register, the surface of 
which was evenly indented, to the depth of 
0.1 of an inch, as if it had received the im- 
pression of a punch* 
Vox. I. 
FULM1NATION-. 
u The instrument used in this experiment 
being familiarly known, it is therefore ,-carce- 
ly necessary to describe it : suffice it to say, 
that it was of brass, mounted with a spring 
:Agister, the moveable hand of which dosed 
up the muzzle, to receive and graduate the 
violence of the explosion. The barrel was 
half an inch in caliber, and nearly half an 
inch thick, except where a spring of the lock 
impaired half its thickness 
7H0 
u 1 he effects of the "mercurial powder, in 
the last experiments, made me believe that 
it might be conimed, during its explosion, in 
the centre of a hollow glass globe. Having 
therefore provided such a vessel, seven in- 
ches in diameter, and nearly half an inch 
thick, mounted with brass caps, and a stop- 
cock, 1 placed ten grains of mercurial 
. , - 0 powder 
on thin paper, laid on iron wire, 1 49th oban inch 
, | thick, acrossthe paper, throughthe midst eftfae 
“ A gun belonging to Mr. Keir, an inge- i powder, and, closing the paper, tied it fast 
nious artist of Camden -Town, was next j at both extremities with silk to the wire. As 
the inclosed powder was now attached to the 
middle ot the wire, each end of which, was 
charged with 17 grains of the mercurial pow- 
der, and a leaden bullet. A block ol wood 
was placed at about eight yard's from the 
muzzle to receive the ball, and the gun was 
fired by a fuse. No recoil seemed to have 
taken place, as the barrel was not moved 
from its position, although it was in no ways 
confined. The report w as feeble : the bullet, 
Mr. Keir conceived, from the impression 
made upon the wood, had been projected 
with about half the force it would have been 
by an ordinary charge, or 68 grains, of the 
best gunpowder. We therefore re-charged 
the gun with 34 grains of the mercurial pow- 
der ; and as the great strength of the piece 
removed any apprehension of danger, Mr. 
Keir fired it from his shoulder, aiming at the 
same block of wood. The report was like 
the lirst, sharp, but not louder than might 
have been expected from a charge of gun- 
powder. Fortunately Mr. Kier was not 
hurt; but the gun was burst in an extraor- 
dinary manner. The- breech was what is 
called a patent one, of the best forged iron, 
consisting of a chamber 0.4 of an inch thick 
all round, and 0.4 of an inch in caliber; it 
was torn open and flawed in many directions, 
and the gold touch-hole driven out. The 
barrel into which the breech was screwed was 
0.5 ol an inch thick; it was split by a single 
crack three inches long, but this did not ap- 
pear to me to be the immediate effect of the 
explosion. I think the screw of the breech, 
being suddenly enlarged, acted as a wedge 
upon the barrel. The ball missed the block 
of wood, and struck against a wall, which had 
already been the receptacle of so many bul- 
lets, that we could not satisfy ourselves about 
the impression made by this last. 
“ As it was pretty plain that no gun could 
confine a quantity of the mercurial powder 
sufficient to project a bullet with a greater 
lorce than an ordinary charge of gunpowder, 
1 determined to try its comparative strength 
in another way. I procured two blocks of 
wood, very nearly of the same size and 
strength, and bored them with the same in- 
strument to the same depth. The one was 
charged with half an ounce of the best Dart- 
ford gunpowder, and the other with half an 
ounce of the mercurial powder; both were 
alike buried in sand, and fired by a train 
communicating with the powders by a small 
touch-hole.' The block containing the gun- 
powder was simply split into three pieces: 
that charged with tiie mercurial powder was 
burst in every direction, and the parts imme- 
diately contiguous to the powder were abso- 
lutely pounded, yet the whole hung together, 
whereas t he block split by the gunpowder 
had its parts fairly separated. The sand sur- 
rounding the gunpowder was undoubtedly 
most disturbed : in short, the mercurial pow- 
der appeared to have acted with the greatest 
energy, but only within certain limits. 
5 G 
connected with the bra 
powder became, bv this disposition, fixed in 
the centre of the globe. Such a charge of 
an electrical battery was then sent aloes; the 
wire, as a preliminary experiment (with" Mr. 
C uthbertson’s electrometer) had shewn me 
would, by making the wire red hot, inflame 
the powder. The glass globe withstood the 
explosion, and of course retained whatever 
gases were generated ; its interior was thin- 
ly coated with quicksilver, in a very divided 
state. A bent glass tube was now screw ed 
to the stop-cock of the brass cap, which be- 
ing introduced under a glass jar standing in 
the mercurial bath, the stop-conk was open- 
ed. '1 hree cubical inches of air rushed out, 
and a fourth was set at liberty when ihe ppa- 
ratus was removed to the water" tub. 'I lie 
explosion being repeated, and the air all re- 
ceived over water, the quantity did not vary. 
'Io avoid an error from change ot tempera- 
ture, the glass globe was, both before and 
after the explosion, immersed in water of the 
same temperature. It appears, therefore, 
that the ten grains of powder produced four 
cubical inches only of air. 
“ To continue the comparison between the 
mercurial powder and gunpowder, 10 nr. ips 
of the best Dartford gunpowder were hi a 
similar manner set fire to in the glass globe: 
it remained entire, 'i he whole of the pow- 
der did not explode, for some co , picte 
grains were to -be observed adhering to the 
interior surface of the glass. Litt’e need be 
said of the nature of the gases generated dur- 
ing the combustion of the . gunpowder*: they 
must have been carbonic acid gas, sulphu- 
reous acid gas, nitrogen gas, and (according 
to Lavoisier) perhaps hydrogen gas. As to 
the quantity of these, it is obvious that it 
could not be ascertained; because the two 
first were, at least in part, speedily absorbed 
by the alkali of the nitre, left pure after tiie 
decomposition of its nitric acid.’’ 
The following description will give the ex- 
perimental philosopher a clear idea of the in- 
strument used in this business. 
The ball or globe of glass is nearly half an 
inch thick, and seven inches in diameter. It 
has two necks, cm which are cemented two 
brass caps, each being perforated with a fe- 
male screw, to receive the male ones: through 
the former a small hole is drilled ; the latter 
is furnished with a perforated stud or shank. 
By means of a leather collar the neck can 
be air-tightly closed. When a portion of the 
powder is to be exploded, it must be placed 
on a piece of paper, and a small wire laid 
across the paper, through the midst of the 
powder : ( the paper being then closed, is to 
be tied at each end to the wire with a silken 
thread. One end of this wire is to he fast- 
the packet of 
