1872.] British Artillery Matériel. 233 
II. Gunpowder Service P.* (as the pebble-powder described 
in the last number of the ‘‘ Quarterly Journal of Science” is 
officially designated) is to be introduced for battering charges 
of all rifled guns of 7-inch calibre and upwards, and for all 
service-charges of 40 lbs. and upwards, so soon as a sufficient 
quantity has been manufactured. 
III. Additional experimental proof of the special value of 
compressed gun-cotton for demolition of stockades, bridges, 
&c., and for submarine mines. Capt. Noble also proposes 
to apply gun-cotton yarn as a fuze priming, it possessing the 
advantage of consuming almost instantaneously, thus not 
interfering with the burning of the fuse, whilst its sensitive- 
ness makes ignition certain, even by the lowest charge. 
IV. ‘‘ Picric powder” is not unlikely to be used in future. 
It is an invention of the War Department chemist, Mr. Abel, 
who has been designing this explosive agent specially pro- 
vided for charging shells. This mixture is neither so violent 
in its aétion as gun-cotton, nitroglycerine, or picrate of 
potash powder, but at the same timeis a much more power- 
ful explosive than gunpowder, and has other properties 
which appear to render it peculiarly adapted for employment 
in shells; it is readily and expeditiously prepared, can be 
pressed and granulated without difficulty, andat the same time 
is particularly remarkable for its safety as compared with all 
other explosive agents; it is, in fact, somewhat less sensitive 
to ignition by percussion than gunpowder. By recent expe- 
riments made it appears that picric powder, when used as a 
bursting charge for Palliser shells, will sustain the action of 
battering charges of R.L.G. powder in guns up to and in- 
cluding the g-inch of 12 tons: the safety of this substance is 
being further tested from 10-inch and 12-inch guns. 
V. The last explosive compound to be noticed, as likely 
to take no small part in future warfare, is Kreb’s patent 
* lithofracteur,” which is in use in the Prussian service. 
From Mr. Abel’s analysis it appears to be composed as 
follows :— 
PCLOSIVCERING 5 ny ee 6 eats 
Riteepe ere sodae yo... ee Serial st ee he 
SUG i Sa ies Moai dali hide slnenat as ” 
Sand, siliceous earth, sawdust, and 
EGarsely-powdered coal. . 9. : 20" ‘5, 
TOON 755 
* See ‘Modern Cannon Powders,” Quart. Journ. of Science for January, 
1872, p. 58. 
VOL. Il: (N.S.) 28 
