566 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[January 18, 1873, 
would be secured. The difficulties which have since 
been encountered in moderating and regulating the ex¬ 
plosive force of gunpowder when employed in the large 
charges which have now to be used in heavy guns show 
how remote is the prospect of successfully applving ex¬ 
plosive agents more rapid and violent in their action 
than gunpowder to artillery, with the exception perhaps 
of the smallest calibres. 
The numerous attempts to apply substitutes for gun¬ 
powder in small arms have in some instances been at¬ 
tended with partial success. Many of these have dif¬ 
fered greatly from each other, but all of them have been 
more rapidly explosive and therefore more violent and 
destructive in their action than powder. Gun-cotton in 
one form or another has been repeatedly made the sub¬ 
ject of patient experiment as a material for use in small 
arms. The first attempts at its employment, made soon 
after its discovery in 1846, were disastrous in their re¬ 
sults, and the success which long afterwards was be¬ 
lieved to have been achieved, by Yon Lenk’s indefati¬ 
gable labours, in the production of a safe and uniform 
cartridge, ingeniously constructed of layers of braided 
gun-cotton threads, was not confirmed by experience. 
Several methods of reducing the rapidity and increasing 
the uniformity of action of gun-cotton in small arms 
have since been made the subject of experiment in Eng¬ 
land. Some of these, which consisted in the uniform 
dilution of gun-cotton either with ordinary cotton or 
with less explosive varieties of the material, have fur¬ 
nished fairly-efficient cartridges for sporting purposes, 
which, though wanting much in uniformity, have esta¬ 
blished for themselves a superiority over gunpowder in 
regard to freedom from smoke and fouling, and one or 
two other qualities. But the only direction in which 
substantial prospect of success has hitherto attended the 
use of gun-cotton cartridges in arms of precision has 
oeen the. conversion of gun-cotton pulp by moderate 
compression into very uniform masses, the rapidity and 
violence of explosion of which were retarded by impreg¬ 
nating these throughout with some perfectly inert ma¬ 
terial, thus enveloping each joarticle of gun-cotton in a 
film of non-explosive substance. The experiments upon 
this system of preparing cartridges have not been pur¬ 
sued for the last four years, but some very good targets 
at 500 yards .were made with the service Enfield and 
fenider arms in 1867 and 1868, with cartridges of gun¬ 
cotton impregnated with small quantities of paraffin or 
stearin. India-rubber has also been employed in a 
similar manner as a retarding, and, at the same time, 
water-repelling agent. Considerable success has recently 
attended repeated trials with a species of gunpowder 
devised by Mr. Punshon, in which the principle of dilu¬ 
tion of gun-cotton is also adopted, this explosive being 
incorporated with, sugar and saltpetre. A preparation 
of somewhat similar nature, containing as one compo¬ 
nent an imperfect kind of gun-cotton made from saw¬ 
dust, and known as Schultze’s powder, has also acquired 
some reputation, though scarcely bidding fair to compete 
in uniformity of action with the excellent gunpowder 
now manufactured for breech-loading rifles. 
The application of powerful explosive agents in shells 
would appear at first sight to present little difficulty, be¬ 
yond that involved in the selection of a material which 
presents a decided advantage in point of disruptive 
power over gunpowder, without exerting an excessive 
disintegrating, action upon the mass of the shell, and 
thereby effecting its comparatively harmless dispersion. 
An important obstacle to the employment of many of 
the more powerful explosive agents as charges for shells 
exists in their, liability to premature explosion by the 
concussion which the shell has to sustain upon the dis¬ 
charge of the gun. Attempts to employ gun-cotton in 
shells have several times been attended by such prema¬ 
ture explosions, more or less disastrous to the guns 
used. In comparing the relative sensitiveness to explo¬ 
sion by a blow or concussion of different compounds and 
mixtures, their submission, under precisely similar con¬ 
ditions, to the blow of a weight falling from measured 
heights has furnished satisfactory results, and by pur¬ 
suing this line of experiment, very useful data have 
been obtained. The conditions which are variable in 
such experiments require, however, very careful regula¬ 
tion, as the results attained may be modified to almost 
any extent by variations of such elements as the area of 
the surface of material struck, the thickness of the mass, 
its mechanical condition (whether in coarse or fine 
powder, or in a rigid or plastic mass), the nature of the 
materials composing the weight and the anvil or sup¬ 
port. Thus, a layer of mealed powder 0 - 05 inch thick 
placed between two flat brass plates one inch square is 
exploded by the blow of a 50-lb. weight falling from a 
minimum height of 36 feet, while a layer of the same 
thickness placed between brass plates like the preceding, 
but 0'5 inch square, is exploded by a fall of the 50 lb. 
from a height of about 9 feet. Small flat charges of 
fine-grain powder weighing five grains, enclosed in tin- 
foil and placed upon a steel support, were always ex¬ 
ploded, in ten successive experiments, by the fall of a 
steel 25-lb. weight from a height of 2 feet; when a brass 
support was substituted for that of steel, only four 
charges out of ten were exploded; when both weight 
and support were of brass, only two out of ten were 
fired, and when the support and weight were of lead or 
wood, no explosion was obtained even wffien the weight 
fell from a height of 40 feet. Again, a nitro-glycerine 
preparation, of which a layer of a particular thickness, 
placed between brass plates resting on a solid block of 
iron, was exploded by a fall of a 50-lb weight from a 
height of 2 feet, was not exploded by a fall of 40 feet, 
when the lower brass plate was fixed upon a wooden 
block, the upper plate being attached to the weight by 
means of a small block of wood. 
Of the many explosive preparations more violent than 
gunpowder which have been submitted to comparative 
experiments of the above nature, a mixture of ammo¬ 
nium picrate with saltpetre proved the least sensitive to 
explosion by blow, thus contrasting remarkably with 
the violently explosive mixtures of potassium picrate, 
which have been made the subject of experiment in 
France. Picric acid, which is now manufactured ex¬ 
tensively for tinctorial purposes by the action of nitric 
acid upon phenol or carbolic acid, has been known since 
the end of last century as capable of furnishing explo¬ 
sive mixtures. Some of its salts, such as those of potas¬ 
sium and barium, are of themselves explosive, and 
furnish violently detonating mixtures with saltpetre and 
potassium chlorate. The mixtures of ammonium picrate 
with these salts, though less powerful in their action, are 
considerably more so than gunpowder, and the saltpetre 
mixture which has been called picric powder, has been 
shown by extensive experiments to be as safe as powder 
in manufacture and use, and as permanent in character; 
shells charged with it have been repeatedly fired from 
guns of large calibre, with heavy powder-charges, and 
there appears strong reason for placing confidence in this 
material as fulfilling the conditions, in regard to safety 
and power, of a very efficient powder for shells. 
Most important progress has been made, during the 
last few years, in the application of explosive agents, 
more violent than powder, to mining and quarrying, 
and to various civil and military engineering purposes. 
The hope of realizing the advantages which would be 
secured, especially in point of economy in time and 
labour, by an explosive agent combining increased 
power with other essential qualities of a practically use¬ 
ful material, has led to the production of a great variety 
of preparations designed to serve as powder-substitutes 
in its industrial applications. The powerful oxidizing 
agent potassium chlorate has thus been applied in nu¬ 
merous ways; and some of its preparations, of compara¬ 
tively safe nature, such as Horsley’s and Ehrhardt’s 
powders, have afforded prospect of advantageous em- 
