The San Francisco call., 1897-02-09
ECHOES OF THE
COAST DEFENSE
Testing a Ten Inch Gun
on a Disappearing Car.
riage.
The Manner in Which a Thirty.
Ton Piece of Ordnance Is
Loaded.
What It Costs to Fire the Various
Kind; Of Guns That Are Now
Being Mounted For Urcle Sam.

The echoes of the big 10inch rifed
gun, which has been recently mounted on
the bluff south of Fort Winfield Scott,
were heard for miles around yesterday
afternoon.
This gun, which is mounted on a disap-
pearing carriage, is the first of its kind
ever mounted on this coast, and is the
first ever tested here. The test yesterday
was for powder and for the purpose of see
ing how the machinery that causes the
''long black monster" to drop down below
the level of the pit on which it is mounted
would work.
The first test was noted by Colonel w.
r. Shafter, Lieutenant-Colonel Samuel B.
NJ. Young, large number of officers from
the Presidio and quite a number OF citi-
zens.
The gun, which weighs 81. 110 pounds,
or nearly thirty tons, is on an immense re-
voiving carriage to permit the training of
the piece in any direction. On this car
riage are two very heavy levers, on which
the gun rests. When they are elevated
the piece is above the upper edge of the
pit, and when q shot is fired the recoil
forces these down and brings the breech
of theg to the level of the loading plat
form. AS the gun descends four steel
clamps drop against rachets and hold the
gun to the level at which it dropped until
they are released, and then a counter
weight heavier than the gun sinks and
brings the rife TO the firing position. The
machinery works with the exactness of
c,ockwork and is marvel of mechanical
ingenuity.
The proiectiles used are long and conf
cal-shaped, and weigh 562 pounds; the
charges OF powder used yesterday varied
from 162 to 280 pounds. The gun can, by
an auxiliary device, be dropped by
manual force. This was done yesterday for
the first charges.
The loading of big gun is an interest
ing process. Two o. the Runners roll the
proJect1le to point almost under the gun
which has the oreech block open; there it
is rolled into an iron scoop. This is taken
up by block and tackle attached to a
running crane, and bv means of a crank
roller the projectile is raised to the level
of the opening in the breech, carefully
pushed into it and then rammed home by
eight gunners using very long rammer.
The first test yesterday was with 1872
pounds OF powder. There was a LOUD
report, great volume of smoke, and more
than mile away the spray climbed high
in the air 10 show where the shot had
struck the water.
In the meantime, the big gun by the
force of the recoil, dropped, but the
clutches not working with the precision
expected, the gun returned TO its high
position.
The next test was with $50 pounds of
powder, and that was more satisfactory,
although the gun had to be lowered by
hand.
The third was with $50 pounds OF pow
der, and. the recoi being greater the
mechanism worked better, but the success
of the disappearing apparatus will not be
determined until further tests are made
The cost of firing big guns is no small
item, as appears from the following from
a report from the office of the Secretary of
War: 1T costs for powder and proiectiles
alone: To fire one round from the eight
inch B. L. rifle, 1854 55; ten-inch B. L.
rifle, 1922 40; twelve-inch B. L. rifle,
$56l 20; twelve-inch B. L. mortar. $219 65;
eight-inch pneumatic gun, $3.50; fifteen
inch pneumatic gun, $3.50"
According to these figures the tests yes
terday cost the Government 1867 20.