GUNPQWDER. 
else that it has too much charcoal in it ; so 
also if rubbed upon white paper it blackens 
it more than good powder does ; but if it 
be of a kind of azure colour, somewhat 
inclining to red, it is a sign of good pow- 
der. 2. By touching ; for if in crushing it 
with the fingers’ ends, the grains break ea- 
sily and turn into dust, without feeling hard, 
it has too much coal in it ; or if, in pressing 
it under the fingers upon a smooth hard 
board, some grains feel harder than the 
rest, it is a sign the sulphur is not well 
mixed with the nitre. Also by thrusting 
the hand into the parcel of powder, and 
grasping it, as if to take out a handful, you 
will feel if it is dry and equal grained, by 
its evading the grasp and running mostly 
out of the hand. 3. By burning ; and here 
the method most commonly followed for 
this purpose with us, says Mr. Robins, is 
to fire a small heap of it on a clean hoard, 
and to attend nicely to the flame and smoke 
it produces, and to the marks it leaves be- 
hind on the board ; but besides this uncer- 
tain method, there are other contrivances 
made use of, such as powder-triers, acting 
by a spring, commonly sold at the shops, 
and others again that move a great weight, 
throwing it upwards, which is a very bad 
sort of eprouvette. 
The best eprouvette consists in a small 
cannon, the bore of which is about one 
inch in diameter, and is usually charged 
with two ounces of powder, and with pow- 
der only, as a ball is not necessary, and the 
strength of the powder is accurately shown 
by the arc of the gun’s recoil. The whole 
machine is so simple, easy, and expeditious 
that, as Dr. Hutton observes, the weighing 
of the powder is the chief part of the trou- 
ble, and so accurate and uniform, that the 
successive repetition, or firings, with the 
same quantity of the same sort of powder, 
hardly even yield a difference in the recoil 
of the one hundredth part of itself. 
To recover daviaged powder. The method 
of the powder merchants is this : they put 
part of the powder on a sail-cloth, to which 
they add an equal weight of what is really 
good, then with a shovel they mingle it 
well together, dry it in the sun, and barrel 
it qp, keeping it in a dry and proper place. 
Others again, if it be very bad, restore it 
by moistening it with vinegar, water, urine, 
or brandy ; then they beat it fine, sift it, 
and to every pound of powder add an 
ounce, or an ounce and a half, or two 
ounces (according as it is decayed) of 
melted nitre, and afterwards these ingre- 
dients are to be moistened and well mixed, 
so that nothing may be discerned in the 
composition, which may be known by cut- 
ting the mass, and then they granulate it as 
useful. In case the powder be quite spoiled, 
the only way is to extract the salt-petre 
with water, in the usual way, by boiling, 
filtrating, evaporating, and crystallizing, 
and then with fresh sulphur and charcoal 
to make it up afresh. 
On the subject of gunpowder, see also 
Euler on Robins’s Gunnery, Antoni Exa- 
men de la Poudre, Baume’s Chemistry, and 
Thompson’s Experiments in the Philos. 
Trans, for 1781. 
Soon after the discovery of the oxyge- 
nated-muriatic acid, and its combination 
with potash, it was found that this oxymu- 
riate produced a much more violent deto- 
nation with combustible bodies, than is 
afforded by nitre. It has been estimated 
to possess more than double the force : but 
on account of this extraordinary power in 
gunpowder made with the new salt, and 
some fatal accidents by its exploding in 
consequence of friction or percussion to 
which it is liable, as well during the manu- 
facture as afterwards, this modern com- 
pound has not been brought into use in 
military operations, but is likely to conti- 
nue among the articles of scientific curio- 
sity. 
Gunpowder and Combustibles. No per- 
son shall make gunpowder but in the regu- 
lar manufactories established at the time of 
making the statute 12 George III. c. 61, 
or licensed by the sessions, pursuant to 
certain provisions, under forfeiture of the 
gunpowder, and two shillings per pound; 
nor are pestle mills to be used under a 
similar penalty. 
Only forty pounds of powder is to be 
made at one time under one pair of stones, 
except Battle-powder, made at Battle and 
elsewhere in Sussex. 
Not more than forty hundred weight tq 
be dried at one time in one stove ; and the 
quantity only required for inimediate use 
to be kept in or near the place of making, 
except in brick or stone magazines, fifty 
yards at least from the mill. . 
Not more than twenty-five barrels to be 
carried in any land carriage, nor more than 
two hundred barrels by water, unless going 
by sea or coastwise, each barrel not to 
contain more than one hundred pounds. 
No dealer to keep more than two hun- 
dred pounds of powder, nor any person 
not a deqler, more than fifty pound in the 
