The herald., 1895-09-05
Receives the Impact of Balls
From l2.Inch Guns
THE PROJECTILES HARMLESS
They Mar Her Plates but Do Not Start
Her Frame
First Trial Ever nade Against Hull construc-
-. tion in Naval Gun Tests-Resump-
tion OF Construction
Associated Press Special Wire.

WASHINGTON, Sept. 4.-The battleship
lows will withstand the projectiles of
the best 12-inch gun afloat. That was the
conclusion drawn today from one of the
most important tests ever made at the
government proving grounds at Indian
Head. Since the equipment of modern
battleships with heavy armor, there has
been in certain quarters question as to
whether the framework of ships so armor-
ed could resist the crushing force of blow
from one of the big guns. even though
the ermor itself was capable OF keeping
the prolectiles out. Hitherto all tests
of armor have been made against un-
yielding wonden butts. Today the United
States for the first time since the use of
modern guns and armor began experi-
menting to determine the actual strain
and injury to which battleship would
he subjected ii struck by proiectile. For
that purpose side armor plate of the
battleshp Iowa, now. building at the
Cramps yards in Philadelphia, was
fitted up on an actual production of .
section of the ship. 1t consisted of the
inner and outer bottoms of tve-eighths
inch steel, forming com partments with
lateral steel bulkheads four feet apart.
Outside the outer bottom was a skin
Of five-eig ghths steel and between this and
14-inch armor plate, where ten inches
of solid oak backing. Above was the
projection deck and below the main deck
the whole being backed above and be low
by oak, of the estimated strength OF the
projection and main deck. The plate
itself was sixteen feet by seven and one
half feet fourteen inches thick at the top
and sloping towards the bottom to
thickness of seven inches.
y The character of the test was such ,h at
Secretary Her bert himself went down the
river to witness it, and there was more
than the usual number Of officials present
from the ordnance and construction bu-
reauS.
The shots were at $50 yards at right
angles to the plate to secure the norma II
impact. The first shot was 500-pound
Carpenter projectIle from ten-inch gun,
driven by 40 pounds of Dupont's brown
prismatc powder. 1t struck the plate
with velocity of 1882 feet per second, or
with an energy OF 741, 600 pounds. The
projectile was driven into the plate about
six inches and not single injury TO the
hacking was discovered after a careful
examination, save the shearing of nine
bolts connecting the projection deck with
the armor. This was not considered
serious.
The second shot was also from q ten
inch gun. but the powder charge was IN
creased to PIG pounds, which increased
the velocity to 1862 feet per second, so
that it struck with an enerey of 931, 900
pounds. The shot also spent itself on the
plate without creating a sign of a crack
or injury or straIning the frame WORK.
There was not bulge in the plate or
frame of the vessel single bolt, how
ever, was driven out.
Having thus tested the 14-inch plating
it was decided to subject the frame work
to % still severer test and S50-pounu
Wheeler sterling shell driven bv AGO
twelve inch gun. The projectile struck
with velocity of 1900 or an energy of
| $50, 900 foot pounds. This shot would
according to the estimates have pene-
trated a l6-inch Harveyized plate.
Although it cracked the plate already
penetrated the wood backing it did not
get through the backing. The enormous
recoll of the plate, however, pulled it from
the wood about three-fortieths of an
inch. 1t also struck close to bolt and
sent it with tremendous force across the
compartments against the inner bottom
which was bulged but not penetrated.
The outer bottom was slightly bulged
also and the bulkhead where the sh
struck was buckled.
| On the whole the result of the test
with the plates and frame work WAS con-
sidered remarkable. The plate withstood
| the government test for 16-inch plate
| splendidly and cUnstructively tho test of
| 17-inch plate. The resistance of the
| frame really astonished all. Secretary
| Herbert was greatly rejoiced at the result
and Catpain Sampson. chief of the ord
nance bureau, said the injury both to the
| plate and frame was the very minimum
| WI tl,ctn ba
better than we hoped it would, 'said Cap
| tain Sampson.