STEEL AS APPLIED TO ARMOUR. 
233 
Bound 5.—The shell got through the plate, and two of the cracks 
made by it were through at the edge. 
This plate then stood a remarkable trial, and, spite of one's objec¬ 
tions to the system by which the hard face is joined to the back, it 
must be a subject for congratulation that an English firm have 
succeeded in making such a plate. 
Against this plate the best forged steel projectiles flew to pieces, 
the hard face breaking them up, and so they delivered only a portion 
of their energy into the plate. The warping of the plate here noticed 
is serious, but Messrs. Brown state that they can obviate this entirely, 
and also hope that they will be able to apply the process successfully 
to curved plates. 
Another trial of these plates took place afterwards at Portsmouth, 
when they were equally successful, breaking up all the projectiles, and 
the greatest bulge at the back of the plate being only 0*9 inches. 
This plate appears not to have been warped at all : its size was 
8' x 6' x 10*5 . 
Now to turn to the trial of a “ Harveyised" plate, carried out at 
India Head, United States, on November 14th, 1891. This plate was 
of nickel steel, the carbon being 0*31 per cent, and nickel 3*07. The 
dimensions of the plate were 8' x 6' x lO’S." The four first rounds 
were fired from the 6-inch B.L. high-powered rifle; the projectiles 
were Holtzer armour-piercing shells, weighing 100 lbs., the striking 
velocity was 2075 f.s. 
The fifth round was fired at centre of plate from an 8-inch B.L. 
high-powered rifle, with a steel shell, hardened by the Firminay process, 
weighing 210 lbs., and striking with a velocity of 1850 f.s. 
The annexed sketch is only to give a rough idea of the Harvey 
plate and is in no way official, but is intended to assist the description 
of the trial. 
Cracks marked “ T ” are through. 
Bound 1.—The shell was broken into a great many pieces, the point 
fragment being about the size of a small flat peg-top. The pene¬ 
tration was about 12 inches ; there being a considerable amount of 
chipping round the hole, with no bulge. 
Bound 2,—The shell broke into so many small fragments that only 
