488 
ARMOUR-PIERCING PROJECTILES. 
internal arrangements. In tlie fuzes intended to fire wet gun-cotton 
of course dry gun-cotton and a detonator had to be used. 
The object of the delay action was to allow the shell to get clear 
away from the gun before exploding, in the event of the fuze acting 
prematurely; and to allow the shell to penetrate a ship^s armour before 
exploding, thus tending to blow off the armour plates within. It was 
obviously necessary to use shell which did not break up on impact, so 
Whitworth forged steel shells were employed. 
Certain preliminary experiments were made, which established—■ 
(1) That a dry gun-cotton primer and detonator could be put in 
the base of the shell, so as not to explode on impact against armour. 
It followed from this that the construction of a delay-action was 
possible. 
(2) That a bursting charge of powder in a steel shell could not be 
restrained from igniting on impact, even when enclosed in several 
layers of serge or silk cloth. 
(3) That the bursting charge of powder which could be contained 
in an armour-piercing projectile could not break up tough steel shells. 
(4) That a shell containing wet gun-cotton (17 p.c. moisture) 
would not ignite on impact against armour. 
The trials with shells filled with wet gun-cotton, and fitted with faze 
and primer, &c., complete were now proceeded with. 
Five Whitworth shells were fired in this condition, each held about 
3 lbs. 6 ozs. of wet cotton. 
The results of the trials were— 
First, as to security to the gun. No shell exploded till after impact 
with the target, and so far the result was satisfactory, but the small 
number of rounds made it impossible to state dogmatically that there 
was no risk to the gun in the use of such shells. 
Secondly, as to the amount of delay between the impact of the shell 
and its explosion. The amount of delay expected from the fuze was 
5 secs., and one did so act when ignited at rest in a shell filled with 
wet gun-cotton. In the firing, however, this amount of delay was 
obtained in no instance, barely enough being obtained to allow the 
shell to get through the plates. The Committee thought that this 
might be due to the fuze composition having to burn under great 
pressure, and that more satisfactory results might be obtained by 
allowing a larger slowing chamber, or providing some means of escape 
for the gas. Possibly, however, the shock of impact disintegrated the 
fuze composition, and made it burn almost instantaneously. It was 
recommended that, if possible, some mechanical means of obtaining 
delay should be tried, as involving less risk. 
Thirdly, as to the destructive effect produced by a bursting charge 
of wet gun-cotton, as compared with one of gunpowder in shells of 
similar capacity, it had been shown that gunpowder was useless as a 
bursting charge in good steel shells, as it failed to break them up, 
while gun-cotton did so. 
