1872.] Modern Cannon Powder. 63 
points is known, and the velocity with which it is moving is 
readily ascertained, and affords a direct indication of the 
strength and uniformity of the powder. Every kind of 
powder now passed into the service is subjected to this 
proof, in addition to being tested by the mercury densimeter. 
We have stated that R.L.G. powder was adopted in 1860 
for our breech-loading guns, and that its use was afterwards 
extended to the charges of all rifled guns. When, however, 
the size of our heavy ordnance was increased more and more, 
it soon became apparent that even this powder was totally 
unfit for the large charges then used, and its violent action 
earned for it abroad the unenviable soubriquet of “‘ poudre 
brutale.” 
In the year 1858 the gunpowder question was referred to 
a Committee, composed of the Superintendent of the Royal 
Gunpowder Factory, the Superintendent of the Royal La- 
boratory, and the Chemist to the War Department ;* and it 
was, in fact, some of the earlier experiments of this Com- 
mittee that led to the introduction of A, or R.L.G. 
powder. The means at their disposal for determining the 
manner of combustion, and the pressure exerted upon 
the gun by different kinds of powder, were very limited. 
Nevertheless the conclusions they arrived at, as set forth in 
their Reports of 1859 and 1866, were very correct, and have 
been entirely corroborated by subsequent researches. As 
early as 1860 they had satisfactorily proved that the density 
and hardness of powder exercise an important influence on 
its character, and in all their subsequent experiments these 
points were strictly attended to. In their final report (1866) 
they recommended the adoption of a cylindrical ‘‘ Pellet” 
powder of a density between 1°492 and 1°50, but pressed 
comparatively wet, so that, though light, the powder should 
beratherhard. The form of this powder is shown at Fig. 1, 
Plate I., the cavity or indentation having been introduced in 
order to increase the surface exposed to ignition. This 
powder was adopted entirely upon experiments carried on 
with various natures of Armstrong breech-loading guns and 
smooth-bored mortars, and it is evident that a light, but 
hard, powder, such as this is, which would be slow lighting 
but quick burning, would be exactly suited to breech-loading 
guns, in which the initial resistance of the tight-fitting, lead- 
coated projectile is very great, as the lead has to be bodily 
forced forward into the grooves of the rifling. 
B sais Askwith, R.A.; Captain Boxer, R.A.; and F. Abel, Esq., R.A., 
