Pittsburg dispatch. [volume] (Pittsburg [Pa.]) 1880-1923, 1891-11-01
AMERICA IS AHEAD,
Successful Tests Of Homemade Armor
Plate at Indian Head.
THE FOREIGN METAL NOT AS GOOD.
Carnegie, Phipps & Co.'S Harveyized Steel
Proves an Eye-0pener.
THE BETHLEHEM PLATES ALSO SUPERB

rfRoM A STAFF CORRESPONDENT
| WASHINGTON, Oct. 31.-If there was
anv doubt about the ability of American
manufacturers to turn out successful armor
plates, it was dispelled by the results of to-
| DAVIS test at the Indian Head naval ord
nance Proving grounds. A year ago last
September, when three foreign-made plates
were tested at Annapolis, no one in this
country had yet made armor plate. To-day
three plates, representing two makers. were
tried, and at least one of them was better
| than the best tried at Annapolis.
The plates tried to-day were the first lot
of eight that has been ordered for the pres
ent series of tests. They included high
carbon nickel-steel plate from the Bethle-
hem Iron Works, containing about per
cent nickel and So per cent carbon; a low
carbon niekel-steel plate from Carnegie,
Phipps & Co., containing the same percent
age of nickel and but % per cent carbon,
| and low carbon all-steel plate treated by
the Harvey process Of superficial carboniza-
| tion from the Bethlehem Iron Works. The
plates were made for the purposes Of COM
parison of the same dimensions as those
tried at Annapolis-eight feet high, six
feet wide and 10H inches thick.
Conditions OF Yesterdays Test.
Five shots were fired at each plate-four
from six-inch gun and one from an eight
inch gun. The powder charge in the six
inch gun was 42.4 pounds. giving a striking
velocity of 2,075 feet per second. In the
eight-inch gun the powder charge was 7414
pounds, and the striking velocity was l, $50
feet per second. These were the same We
locities used in the Annapolis trials.
4 - Ok Il G~>I -
notify everyone on the grounds to get under
cover, and the members of the Trial Board
and spectators got under the bomb-proofs.
The first shot was then fred at the upper
left hand corner of the high carbon nickel
steel plate-the point of impact was two feet
from the top edge and two feet from the LETT
side. The penetration was IS inches from
the surface of the plate. The shell re-
bounded 81 feet, and was picked up intact,
except the rotating band, which was not
found. The hole in the plate was smooth,
and the back of the plate was bulged with
star-shaped cracks where the point of the
shell had broken through. A fringe Of
metal an inch in length was raised up
around the hole. The plate was broken
through. but it had accomplished its work Of
keeping the she'll out.
What the Second Shot Showed.
The second shot was fired at the upper
left hand corner of the low carbon nickel
staNd there, with its base 11A inches be-
yond the face of the plate and its point 17A
inches further on, making the total penetra-
tion in plate and backing 20 inches. The
shell was apparently intact This plate
showed at once a lack of resisting power, as
it allowed the shot to 60 clear through it.
Its low percentage of carbon made it very
tough, however, and it showed less ten
dency to crack than either of the others.
The third shot was at the same corner of
the all-steel plate treated by the Harvey
process, and the shell encountered greater
resistance than in either of the two pre-
vious shots The hard steel surface shat
tered it to pieces, and the point was left
sticking in the plate while fragments of the
base were scattered in all directions. As
the point of the shell plugged up its own
hole it was impossible to measure the exact
penetration of this shot, but it was approx
mately nine inches
Effect on High Carbon Nickel Plate.
The fourth shot was at the upper right
hand corner Of the high carbon nickel plate.
The projectile was broken off in the plate,
the point remaining in. The penetration
was about nine inches.
The fifth shot was at the upper right hand
corner of the low carbon nickel steel plate
and again the too great softness of that
plate was demonstrated by the projectile
going practically clear through it and into
the backing, so that the base of the shell
was nine inches from the face of the plate,
while its point was in the oak backing, 17L
inches deeper. =
The sixth shot was at the Harvey-treated
low-carbon all steel plate, and again the
hardened surface succeeded in smashing the
projectile, the point of which was left in
the plate, as in the first shot. The pene-
tration could not be measured, but from the
point at which the proiectile broke off the
penetration was estimated to be between
seven and eight inches.
The seventh shot was fired at the lower
left hand corner of the high carbon nickel
steel plate and was practically repetition
of the first shot at that plate, the projectile
rebounding entire and leaving hole 13
inches deep.
Low Carbon Nickel Steel Tested.
The eighth shot was at the lower left hand
corner of the low carbon nickel steel plate
As in all the previous shots at this plate,
the she'll remained entire, but this one
did not go in so far. Its base was nearly
flush with the face of the plate and the
point projected through the back into the
plate and backing was about 10 inches
The ninth shot was at the lower left-hand
corner of the Harvey treated all-steel plate,
and it was the first to develop any sign of
weakness in this plate. 1t broke through
the hardened surface, and then the penetra-
tion of the rest of the plate was an easy
matter 1t finally brought up with its base,
81 inches beyond the face of the plate A
deep vertical crack extended from the hole
to the bottom of the plate.
The tenth shot was at the lower right
hand corner of the high-carbon nickel-steel
The shell penetrated 1OH inches and re-
bounded broken up. The hole was clean,
ard the point of the shell did not break
through the back of the plate.
Round No. II was fired at the lower right
hand corner of the low carbon nickel steel
plate, and the shell penetrated 13% inches,
rebounding broken up.
Result of the Twelfth Shot.
The twelfth shot was at the lower right
hand corner of the Harvey treated all steel
plate. The projectile was again defeated
h1-f he hor II o1 4. =.