Rock Island Argus. (Rock Island, Ill.) 1893-1920, 1895-09-05
THs pATTLESHIP IOWA.

resist the crushing force of blow from
one Of the big guns, even though the ar
NOR itself was capable of keeping the pro-
irctilc out. Hitherto all tests of armor
have been made against an unyicldino
wooden butt. Yesterday the United States.
for the first time since the Use Of modern
guns and modern armor, began expert.
mcnts to determine the actual strain and
injury to which Il battlcship would be sub
jcctcd if struck by projectilc
Fixed Up n Section Of the Ship.
For that purpose side armor-plate
of the battlcship Iowa, now building at
the Cramp yards in Philadelphia, was
fitted up on an actual reproduction Of n
section of the ship. 1t consisted of the in
ncr and outer bottoms of fvc-cighths-inch
steel, forming compartments with lateral
steel bultheads four feet apart. Outside
the outer bottom was the skin of five
cighths-inch steel and between this and
the fourtcen-inch armor-platc We're ten
inches of solid oak backing. Above was
the protective deck and below the main
deck, the whole being backed above and
below by oak of the estimated strength of
the main decks. The plate itself was IL
feet by IA, II inches thick at the top and
bloping toward the bottom to "a thickness
uf seven inches.
Secretary Herbert Witnesses the Test.
The Importance of the test was such that
Secretary Herbert himself went down the
river to witness il, and there were more
than the usual number of officers from the
ordnance and construction bureaus. The
shots We're fired AT 80 yards 1T light angles
al
The first was 5OO-lb. Carpenter projcctile
from a tcn-inch gun, driven by no pounds
of Dupont's brown prismatic powder. 1t
struck the plate with velocity Of I,iS.
feet per second, or with an energy Of 7H,-
90 foot pounds. projcctile was driven
into the plate about six inches, and not n
single injury to the backing was discovered
after n careful examination, save the loos-
cning Of seven bolts connecting the pro
lection deck with the armor. This was
not considered serious
Gave It n stiiI Scvcrcr Tcst.
The second shot was also from 10 inch
gun, hut the charge was increased to l6O
pounds, which Increased the velocity to
Ni2 feet per second. SO that il struck with
mn energy of 93l,orO foot pounds. This
shot also spent itself on the plate without
creating sign of u crack, or injury. or
ktruiilinH the framework. There WAS not
u bulge In the platr or frame of the vessel
a single bolt, however, was driven out.
Having thus tested the liinch plate it
was decided to test the frame work To n
still scvcrcr test and an S50-poundW Whecier-
Sterling shell, driven by 100 pounds Of
powder, was fired at 1t from "A l2-inch
gun. The projcctilc struck with a vcloc-
ity Of l,s0. or an energy of $4,000 foot
pounds. This shot should, according to
the most estimates, have penetrated l6.
inch Harvcyizcd plate.
Result Considered Remarkable.
Although il cracked the plate, which
was already wcakcd by the two previous
shots, and penetrated to the wood backing.
il did not get through the backing. The
enormous rccoil OF the plate. however,
pulled it outl from the wood about three
fourths of an inch. Ii also struck close IN
Il bolt and sent IL with tremendous force
across the compartment against the inner
bottom, which was bulgcd, but not pcne-
tratcd. The outer bottom was slightly
bulgcd. also, and the bulkhcad where the
shot struck bucklcd. On the whole, the
result Of the test with the plate and frame
work was considered remarkable. The re-
siStauce Of the framework really aston
ishcd SECRETARY Herbert, who was greatly
rcJuiccd at the result