Year: 1862

September 23d, the first l5inch Monitor
gun, was finished at the Fort Pitt Works.
Pittsburg, Pa. was proved at the Navy Yard
proving grounds. Walls Station, on the Penn
sylvania Railroad. The 1l.inch and 9-inch
Navy guns are taken out on the ordinary plat
form cars and run out on the switch beneath a
stout overhead railway" by means of which
they are transferred. when swung up By screws,
to the proper position for firing the regular
proof of ten service charges.


In order TO sustain the enormous weight OF
the ID inch gun, it has been necessary to re-
build the entire frame in the most substantial
manner and set up a triangle of massive pro.
portions. This triangle is formed by the franz
ing together of two setts of massive timbers in
the shape of triangles, upon the apex of which
2 massive cross timber rests on semi-circular
bearings.


From this cross timber depend the heavy
rods by which the gun is supported-two en-
circlng the trunBion, and the other pair, much
lighter, embracing the breech and supporting
its preponderating weight. Notwithstanding
the enormous weight to be handled, and the in
completeness of some of the arrangements, the
gun was mounted under the active supervision
OF Joseph Kaye, and ready for firing before
five O'Clock.


The first three loads to be fred are proof
charges, composed of Fifty pounds of Rodman's
mammoth grained powder and shell of three
hundred and fifteen pounds. As the firing of
such an enormous lode is very severe test, the
utmost anxiety was felt as the LANYARD was
pulled and the gun discharged. The report
which followed was by no means as heavy as
might have been expected.


The shell struck the ground short distance
in front Of the muzzle glanced up slightly, and
passing through an immense pile of dirt in the
L" bullock pen, buried itself in the hill beyond
The free manner in which the gun is suspended
permits Of the greatest latitude of motion, and
the recol was tremendous in the second round
breaking defective breech rod, and bringing
the trial of the day to summary conclusion
The damage will be repaired and the firing after
another proof charge, continued for some time
with service charge of thirty pounds of pow
der and shell weighing three hundred and
thirty pounds The firing is conducted under
the supervision of Captain Berrieu of the navy
and Lee of the works. The charges already
fired are sufficient test of the endurance of
the gun.


The model Of these guns differs considerably
from that OF the regular 9 aud II inch Dahl
gFehS, ana Sllll more from the model ol the ID
inch Columbiad or Rodman guns As the
iron turrets in which they will be mounted fur
nish but cramped fighting quarters-being gen.
orally of twenty-five feet in diameter-the guns
are made very short in proportion to their cal
iber, being some two feet shorter than the
Rodmaud l5-inch. They are not turned from
the muzzle to the breech, as all other guns
now are, but from line of some seven or eight
inches behind the trunnons of the muzzle, eay-
ing the breech huge unfinished mass


The arrangement of the breech for the oper
ating tackle also differs from the regular navy
pattern, having no horizontal opening for re-
ceiving the hawser and in IFS place a simple
semlclrcuar projection some seven or eight
inches in diameter, and the same in thickness
The trunnionS are much shorter than those of
the regular navy guns, being adapted to an
iron carriage The water circulating core"
now adopted in casting the Coumbiads has
also been adopted to the 15-inch Monitor guns,
all other heavy guns being cast solid. OF
these guns half dozen at least will be requi-
red in a few weeks to arm the Monitors in
course of completion.