Northern tribune. [volume] (Cheboygan, Mich.) 1875-1885, 1883-08-04

This is complex operation, and to
the locker on is decidedly interesting.
The steel is first turned by a steam
lathe working slowly, but with tremen-
dous power, until the heavy mass OF
''steel in the rough" so to speak, be-
comes a long cylindrico-conoidal col
umn. In this condition it is placed in
proper position and hole drilled clear
through it by means of what is called a
"hog Bit" This hog bit is small rec
tangle of very hard steel, turned up at
one end in such manner as to form a
rude vertical section of spherical
triangle. The whole rectangular piece
is then clamped down upon flat shaft
of chilled iron in such manner as to
fit in and form one piece with the shaft.
The latter has at the opposite end a
cylindrical shape, which end is held in
a frame and worked by appropriate
machinery moved by steam upon one
end of the steel column to beperforated.
The end of the column is first "dug
into'' little, and then the ''hog bit"
does its work. 1t revolves on its axis
and the ''bit'' describes circle, tearing
out the hard steel slowly but surely.
AS the guns have a bore of six inches
diameter, and the bit describes circle
of only two and three-fourths inches
radius, the enlargement of the perfora-
ton is accomplished by other bits.
Once perforated, the now hollow
: tubes of steel requires to be ''jacketed"
''collared," and "breeched" before it
is allowed to graduate into the society
of cannon. The jacket is an outside
wrap of steel, followed in the same way,
heated until it expands sufficient to be
Slipped over the tube it is intended to
jacket. Upon cooling this outside wrap
contracts and presses upon the now
inside tube with almost the same degree
of cohesion as the molecules of the steel
themselves. The object of the ''jacket"
is to strengthen the gun and prevent
accident.
The explosive force of the gases
evolved from gunpowder being tremen-
dous, and occurring mostly at the
breech, the primary object is to
strengthen this latter part. Collars of
steel, great blocks of the carbonized
iron, having been turned into shape and
perforated, are next expanded by heat,
and slipped over the breech part of the
gun. When contracting they grow into
and become part of it. The breech
head of the gun is next lathed and fash
toned, different workmen being en-
ployed on different parts of this. The
. rifling of the gun is another step. A
different kind of ''bit'' from the "hog";
a spur of steel tempered to great hard
ness is clamped to the center of semi
circular piece of copper and iron, and
this last device is slowly worked through
the gun on spiral turn, giving the
''rifle twist"
The breech head is then grooved and
adjusted, and the breeeh cap formally
adjusted. This, as is known to all who
have examined breech leaders, swings
back on hinge or spring, and when
closed is securely locked by q lever
clamp.
The body of one of the guns-that is,
the inside tube-is now ready. Work
is being actively pursued on the other
and on the various mechanism that goes
to make up one of the new improved
rihed cannon Some of it, the breech
part especially, is complex, ndrequires
skillful workmen, special tools and a
long time to be wrought successfully
Washington National Republican.