The sun., 1893-07-17
Our Ship Armor and Shells.

the brows OF the stranger within the gates.
Our Ship Armor and Shells.
The trials OF plates and pro1ectiles which
have taken place on the naval proving
grounds at Indian Head during the last
few days possess high degree OF interest
and Importance.
They began with test OF the new Pinch
CARPENTER shells. three OF which were fired
through Creusot plate. wrecking 1t. with
out causing any damage whatever to the
projectiles. As only few years ago no
armor-piercing shells had ever been made
In this country. the supply OF them. OF this
large calibre. and Of quality equal to that
OF the very best HoLTzERs. is most creditable
to America, and another proof that IN the
ordnance material for our ships We are In
dependent OF the world.
The principal trials. however. we're those
OF the plates. The first OF these. a 0-inch
nickel-steel one made by the Carnegie Com
pany as part OF lot Tor tho Monadnocks
side armor. was attacked by an s-inch gun
at distance Of So feet, with HoLTzER shells.
The first shot. with velocity OF l,4O0 feet o
second. got through the plate. penetrating
III inches. but not through the backing:
another. with 1856 feet velocity and 1Ah
inches penetration. also failed to 20 through
the backing. Thus the acceptance OF the
lot Of plates was. secured. An inter-
mediate shot, in which the velocity was
raised to 1858 feet on the chance Of secur.
ing premium. passed through both plate
and target. as Is not strange; but the
great point to note is that there were no
cracks In the plate from any OF tho three
shots. The CARNEGIE works have been be-
hind the Bethlehem in the production OF
thick armor. rs they roll their plates. while
the Bethlehem works forge theirs under an
enormous hammer, and 1t has been found
that their rolling apparatus is not yet equal
to the thickest plates demanded. although
preparations are going on to make it 30.
Meanwhile. an interchange OF contracts for
different thicknesses Of armor has been
effected between the two establishments.
Each success Of the CARNEGIE works In pro-
ducing thicker armor is gratifying, because
1t is an Indication that with the rolling proc
ess. and without the expense OF an enor-
nous hammer. establishments in various
parts OF the United States can compete for
needed portions OF our ship armor.
Still more interesting was the trial OF the
Bethlehem 17-inch nickel-steel plate. one OF
q lot for the barbette armor OF the Indiana.
and hence presenting slightly curved sur
face to the prpjectile. 1t was attacked with O
Pinch rifle $40 feet distant, and 0-pound
CARPENTER shells. In the first trial. with
1921 feet velocity. even the point Of the shell
did not pass through. the penetration being
ICY inches. The second shell. with ,495 feet
velocity second. got its point beyond
the rear OF the plate. the total penetration.
however, being only 20 inches; thus secur-
ing acceptance for the lot. Then came a
premium experiment with an initial We
locity Of 1883 feet. which took the
shell completely through both target
and backing. Here. again. there were no
cracks whatever in the plate, not even
under the tremendous Impact OF the final
shot. which had the enormous energy OF
2l6OO foot-tons. The lesson from this fine
result was that our nlckel-steel armor ls
relatively as efficient in the thickest plates
which will be called for as In the medium
and thin ones OF former trials
not less gratifying was the admirable
performance Of the CARPENTER projecliles.
Those that were recovered from the first
two rounds against the 17-inch plate were
wholly uninjured. the point of the first one
being still actually sharp. 1t Is fair to say
that the HoLTzER shells used against tho
9-inch plate. and recovered after two OF
the rounds. were also In perfect condition;
but there Is no doubt. we understand. that
our American-made armor-piercing projec-
tiles are equal to any In the world.
Yet In certain sense the negative ro-
suits. as they may be called. Of the trials
were hardly less important than the direct
ones already spoken Of 1t is clear that we
must have the HARVEY hardening process
for all our ship plates to which 1t can be
applied. Neither OF the plates just spoken
OF had been subjected to that process.
The fact that one Of the shots against each
plato completely passed through both the
nickel steel and the backing shows that
either would have entered the ship which tho
plate was designed to protect. tits true that
tho shells were delivered with very high
velocities. but not with volocities greater
than can be used in warfare. The targets
were also set up ut short distances from the
guns. and under the most favorable clrcum-
stances for the guns. yet that does not
obviate the need OF surface hardening.
We may conclude. therefore. that Amerl-
can nickel-steel has once more shown itself
to be the best material used anywhere for
ship plates. and that the American HARVEY
carbonizing process added to 1t makes our
armor the best In the world.