The Salt Lake herald. [volume] (Salt Lake City [Utah]) 1870-1909, 1893-07-12
TESTING ARMOR PLATES.
A Series of Experiments of
World Wide Interest.
WHAT THE TESTS WERE FOR.
Plates Resisting Penetration Under
Certain Prescribed Velocity.
Very Satisfactory Results Obtained Both
from the Showing Made by the
Plates, and Also of the Projec-
tiles Used-Experts Happy.

WASHINGTON, July 1.-THE third OF
wide interest and Importance took place
today at the naval proving grounds on
the Potomac river. The tests were for
acceptance and for premium. 1t stipu-
lated that if the plates resisted penetra-
ton under certain prescribed velocity
the makers should receive a premium of
$50 per ton in addition to che contract
price of 500 per ton. The first test was
OF nine inch plate, sample OF the side
OF the armor of the monitor Monadnock.
1t was nickel steel and weighed ten tons,
and was made by the Carnegie-Frick
company. Three Hotter projectiles
weighing 25J pounds each were fired
against it from an eight inch rifle, the
muzzle being fifty-eight feet from the
face of the target.
The first projectiIe had velocity of
400 feet per second at the moment of
impact and penetrated the plate and oak
hacking to depth of III inches. The
second projectile, with a striking velocity
OF ,633 feet, went through the plate and
three feet of oak backing and lost itself
in the earth against which it was built.
The third projectile had velocity of ,536
feet and penetrated the plate and backing
to depth of IL. i inches. The plate we'll
withstood the strain of the attack, no
cracks being perceptlble, ard it fully met
every requirement for acceptance; but the
result OF the second shot deprived the
| makers of any chance for a premium.
Depending on the test was about 250 tons
of plate, involving nearly $3.50, 900.
The second plate was sample of the
curved plates for the barbette on the In
diana, made by the Bethlehem company,
and like the first, was of nickel steel. 1t
| was II inches thick, weighing Biz tons.
1t was subjected to attack from a Pinch
rifle, which threw a monster Carpenter
| shell weighing $50 pounds. Its muzzle
was 31S feet from the face of the plate, the
striking velocity of the first shot was
| /, 1922 feet per second and it penetrated to a
depth OF 1916 inches. A second shot fred
with a velocity of 1 1876 feet per second
and went three inches into the oak back
| ing.
The third and last shot was to determine
whether or not premium was to be paid
and the velocity was raised to 1888 feet
per second. When the dust following the
discharge lifted it was found that the
shell had gone clear through the plate
and thirty-si inches of oak backing and
was then DETECTED into the air and
plunged into the river some hundreds of
| yards away or lost in the woods on the
hillside. The plate secured for the
makers an acceptance of the whole con-
tract, amounting to from 800 to 700 tons,
| but earned no premium.
! Like the Monadnock plates it showed
no cracks under the terrific strain to
which it was subjected. Even more sat-
1sfactory than the showing made by the
plates was that of the prejectiles, eight
inch shells of the Hotter Conical pattern
and twelve inch of the Carpenter onical
pattern. All shells recovered appeared
| wholly unchanged to the Impractical
eye and the gauge showed that they were
disturbed to such small degree that they
might again be fired with the attachment
of new strip for rihing. After the test
was concluded all officials and experts
expressed unbounded qualification at the
| results.