168 
ARMOUR AND ITS ATTACK BY ORDNANCE. 
of the programme was carried out on November 23rd. At this stage 
the St. Chamond plate had clearly behaved the best. The Cammell 
soft steel being placed second. The Tresidder face, however, had done 
its work well. It had broken up the projectiles completely and pro¬ 
tected the backing, but the flaw in the plate had ruined it. 
On December 13th, the Harvey nickel plate made by Vickers was 
tested. Four 6-inch Holtzer projectiles were completely broken on its 
face without making a single crack, with a penetration apparently of 
from 4 to 5 inches. So well did this plate behave, that it was judged 
to have shown itself the best after the fourth round, and the competi¬ 
tion declared to be at an end. A 9-inch shot was then fired at it with 
a striking velocity of 1655 f.s., and an energy given as 7708 foot-tons, 
the projectile weighing about 406 lbs., which seems strange, the service 
weight being given as 275*6 lbs. 403 has since been given as the 
weight. 
This round broke the plate across through the previous points of 
impact, as shown in Fig. 30. A sixth round was fired, a 9-inch pro- 
Fig. 30.—-Vickeks-Haevey Plate. 
jectile being again used, but with a striking velocity of 1889 f.s., and 
an energy of 9974 foot-tons or 867*4 foot-tons per ton of plate. This 
shot broke up, bringing down the entire target. Only one corner of 
the plate, however, was detached from the backing, and one bolt 
broken. 
Nettie trial This was a grand victory for Vicker’s-Harvey plate. With it must be 
Vickers- mentioned a trial which took place at Portsmouth on board the Nettle 
Harvey plate on January 18th, 1893. The plate was only 6 inches thick. It was 
attacked by the 6-inch gun, firing 1001b. Holtzer forged steel projec¬ 
tiles throughout. The first had a reduced charge, giving a striking 
velocity of 1507 f.s. The shot was pulverised without cracking or 
seriously injuring the plate. The second had a striking velocity of 
