The Sunday herald and weekly national intelligencer., 1891-11-15
IMPORTANT ARMOR TESTS.
HIGHLY SATISFACTORY TO THE
GOVERNMENT OFFICERS.
Yesterdays Experiments at the Potomac
River Proving Ground Show Supe-
riority of American Armor for Naval
Ships Over Any Produced Abroad.

Ships Over Any Produced Abroad.
The second of the three competitive tests of
armor plates manufactured in the United
States for modern vessels of war was made
yesterday at the naval proving grounds at
Indian Head, Md, twenty miles down the
Potomac River. The tests demonstrated. in
the opinion of naval officers, that this country
can produce as good, if not better, armor for
naval ships than is produced abroad. Onthe
whole the tests were most satisfactory to
Secretary Tracy and the ordnance board.
The experiments were conducted by the
ordnance board Of the Navy Department, and
were witnessed by Secretary Tracy Senators
Hawley and Morrill,. nearly all the military
and naval attaches of the foreign legations,
Army and Navy experts in ordnance and gun
merry, and many others. The tests were made
to determine the resistance Of armor plate of
three different kinds. The plates were the
high carbon nickel steel plate of Carnegie a.
Co.; thelow carbon nickel steel "Harveyfzed',
plate OF the same firm, and a high carbon
nickel steel plate "Harveyizedn from the
Bethlehem Iron Works. The plates were
each eight feet by six, and arranged in a row.
Fac Each plate was solfdly bolted to three feet of
oak and backed up by bank Of earth. Sides,
plates, and strips supported the plates on ali
sides to make it as firm as possible and as
nearly as possible represent the contiguous
plates OF ships sides. A six-inch, 40
calibre breech-loading rifle was used in firing
twelve out of the fifteen shots fired and was
placed with the end of the muzzle fifty-seyen
feet to the rear of the plates. Five shots In all
were discharged at each plate, four by the six
lncn gun In the Tour corners and one shot in
the centre OF each plate by an eght-inch rifle.
Each plate was ten and one-half inches in
thickness.
The Bethlehem plate contained 35 per cent. of
carbon and 8 per cent. of nickle, the Carnegie
hlgn carbon plate A per cent. of carbon, and
the low carbon plate "a per cent, the percent
age of nickle being the same in all three. The
proJectile OF the six-inch gun weighed 100
pounds, with powder charge of 42 pounds
and an initial velocity of 2070 feet per second.
All Of the projecties used save one were
or the HoltZer make and measured seventeen
inches in length.
upon the conclusion Of the firing with the
six-inch rifle, the eght-inch gun was moved
into condition and one shot fired at the centre
OF each plate, two Carpenter proiec-
tiles with charges of seventy.fou pounds
OF powder being used against the two Carne.
gle plates and Firmfny she'll, 21O pounds In
weight with seventy-two pounds of powder
against the plates of the Bethlehem Company,
II being evident to the board that this plate
had wtthstood the tests better so far than the
others and 1t was, therefore, determined to
give it seyerer test with the larger rifle than
was given the two plates from Carnegie 81
Company. The initial velocity was l, ,750 feet
1HC hibb pldGc urea at was q nigh carbon.
steel plate The shell struck in the centre,
rebounded and dropped to the ground at the
foot OF the plate. Combinations of the cracks
caused by the siX-inch shots followed the
shot, the cracks extending transyersely, then
TO the upper right corner, varying in width
from quarter to three-quarter Inches Pene-
tratlon, nine and five-eighth inches; bulge
twenty inches. With same condition the low
carbon nickel "Harveyized" plate received q:
shot in the centre, causing deep crack from
that made by the first shot at this plate and
extending to the upper right and left corners
OF the plate. These cracks were not nearly
so marked as those of the high carbon plate
Penetration, fifteen and three-eighth inches.
The last shot Of the days test was that with
the heavy charge at the Bethlehem plate.
1fls shot caused the shell to fly back to the
muzzle OF the rife, unfolding itself In the
sand. Two cracks were developed extend
ing from the centre to the right and left up
per and lower corners, but not SO pronounced
AS the cracks In the other plates. The pro-
lectile penetrated twelve and seven-eighths
inches; bulge seventeen inches, with base of
shell split longitudinally and partially spllnt-
cred.
The trials over, Secretary Tracy, Commo-
dore Folger, and the ordnance board
examined critically the effects of each shot on
the plates, and afterward expressed them
selves as much pleased with the days results.
A member OF the board in speaking of the ex-
periments said that any one of the shots
would have gone through the steel armor of
any ship in the world, and exploding would
have destroyed the vessel.