THE ROYAL ARTILLERY INSTITUTION. 
69 
“ The first on Blakely's system (C). The projectiles had no studs, and the 
movement of rotation was given to them by the expansion of the bottom, 
whose edges were forced into the shallow grooves of the bore. 
“ The other, gun was grooved a rayures par alleles (II), and the projectiles 
were provided with studs. 
“ The first experiments shewed that the fire of the latter cannon was more 
regular than that of the former. 
“ In consequence of this, and looking principally to the application of 
expanding bottoms to cannon a rayures paralleled (of which we already 
possessed seven pieces), and for which these bottoms might be very advan¬ 
tageous, the fire of the Blakely gun was suspended in order to continue that 
of the other gun alone. Down to the present time this piece has fired 
fifty rounds, and the result is that the projectiles with expanding bottoms 
are less accurate than the ordinary ones with studs. 
“Considering the small number of rounds fired from this gun with expanding 
bottoms, it was not possible to determine exactly to what degree they answered 
their intended object of preventing the 'wearing of the metal in the bore of 
the gun. 
“ But since experiments had already commenced with breech-loading guns, 
and good hopes were entertained of favourable results, it was decided that no 
further enquiry should be made on the subject of projectiles with expanding 
bottoms, and that all attention should be brought to bear on the enquiries 
which concerned B.L. cannon. 
18. “It may be stated positively that notwithstanding the greater wear of 
metal which occurs in these guns (l’evasement plus considerable) their 
endurance is not affected, because it can be so arranged in loading the gun* 
that the axis of the shot shall be centred very nearly in the bore, which will 
prevent the sticking (obturation) of the projectile. To this it may be added 
that in breech-loading guns the wear is immensely reduced by the hard com¬ 
pression of the lead coating of the projectile,* and after all it must be 
remarked that all breech-loading rifled guns possess a very much greater 
accuracy of fire than is possessed by rifled guns of any system loading at the 
muzzle. 
19. “ The trial of the breech-loading rifled gun of 8*58 inch calibre (I) 
with Krupp's arrangement for closing the breech was commenced by a deter¬ 
mination of its destructive effect on armour plates. The gun was directed 
against a target composed of an entirely new wooden backing resembling the 
side of a ship faced with strong new 4'7 inch iron plates. The first round 
fired was a cast steel shot of 216 lbs., charge 27‘5 lbs. of pellet powder ” 
(distance not stated) “ the projectile penetrated the wood to a depth of 
twelve inches, broke the plate easily (instantanement) and remained buried in 
the backing. The base of the shot projected three inches out of the plate. 
This fresh result was thought sufficient, and the fire at the target was discon¬ 
tinued. The initial velocity of the shot with the charge named above was 
1312 ft. (400 m.), and consequently less than that of a projectile of the same 
& “Hist injiniment moindre par V impression assez forte de la chemise” 
[VOL. V.] 
io 
