Yorkville enquirer. [volume] (Yorkville, S.C.) 1855-2006, 1861-03-07
From the Charleston Mercury.
MILITARY MATTERS.
CASTING PROJECTILEs.

CASTING PROJECTILES.
Solid shot, case shot and shells are cast
at iron.works from white forge iron; for.
merly iron moulds were used for these, but
they had the effect of making the balls too
hard on the surface, whereby the bore of
the gun was injured. At present, there.
fore, all projectlies are cast in sand in
mould-boxes. The casting of solid balls is
the most simple. The patterns for this
purpose are of brass, very exactly turned,
made in two halves, and fitting into each
other by groove; one half has pic screw
ed into it, which forms the hole by which
the metal is poured in at the casting. In
moulding, the grooved half of the pattern
is set upon the mould board, and the tap
hole plr screwed in; then the mould.box is
placed with its key bolts iu the holes made
for them, and half ball moulded by the sand
layer. The mould is then turned over, the
mould-board taken off. the second half ball
set on, the second mould. box placed, and
the mould made in the same way; then the
mould is turned, the pin screwed out, the
moul-box opened, and both patterns taken
out, when it is again clored and is then
ready for casting.
The mould of the hollow shot is more
complicated, because the internal cavity of
these must be formed by core, which re.
T mains in the mould during the casting, and
is removd afterwards; and because, also,
for the larger sizes, pair of ears must be
cast To-, for the shell hooks to catch hold of
in handling them. For hollow shot it is
preferable to have the metal run into mould
at the side, so that the core be not disturb.
ed in its position by the metal falling per-
pendicularly upon it this core is made of
sand or loam the ears are of wrought iron,
and the ends reach into the internal cavity !;
where they are afterwards imbedded in the
metal
MILITARY PYRoTECHNY.
The manufacture of cartridges of all kinds,
and the fireworks generally, especially, fire
and light balls and rockets, for military
purposes, is the object of a particular art
that of pyrotechny.
Musket cartridges consist of a piece Of
paper, one side of which, that it may wind
more closely, is cut obliquely this leaf is
rolled about former, the ball set in, and
the throat choked with tie of linen thread,
and stuck down upon the ball, then the
cartridge is filled and piuched together at
the top, and is ready for use.
Cannon cartridges are made of flannel
bags almost entirely; for marking out the
form upon the piece of stuff, the pattern
board is used. Each calibre has certain
sized pattern board. The length OF the cart
ridge depends upon its being designed to
hold the ball or not. When the bag is sew
ed with the back stitch, turned and felled,
the sabot, which has groove, is set in, the
ball is placed on the saLot, and then the
head is tied. Afterwards the ball is fasten-
ed to the sabot by two strips of tin, crossing
each other at right angles, the bag being
secured to both.
THE "MoRTAR" OF THE ANcIENTs.
As far back as 1928, the French had
short cannon called "BomJards." They
we're first made Of wood, with iron hoops,
and lay upon roller-carriage; they were
afterwards lined with iron plate strengthen.
ed with bars of iron, running lengthwise
the barrel, and bound with iron hoops
But as even this could not withstand the
force of powder, they constructed them of
forged iron-cast iron, and finally of bronze.
All the bombards or mortars shot only
stone balls, or fragments Of iron, and it was
not until the year 400 that iron balls were
used.
SFoRzA had, before Piacenza, in l447,
three Bombards each of which discharged,
in twenty four hours, sixty stone balls, and
with which, in thirty days, be battered
down two towers and the wall between.
IMPROVED MoRTARs OF THE PRESENT
TINE. .-Mortars are in some respects like
howitzers, save that the trunnions, since they
are only designed to discharge shot at
very great elevation, are not in the middle
but at the hinder end; there are some, in
deed, which have, instead of trunnions,
only cast foot, and which can, therefore,
be only fred at one angle. Mortars are
most usually distinguished by the diameter
of the iron shell which fills the bore-thus
we speak of "S, 10 or IL inch mortars,"
the latter of which throws shell of about
100 pounds weight. The internal arrange
ments of the mortar are very different from
the cannon. The charge of powder is very
small in comparrision with the size of the
shot, and is compressed into small cham.
Der made for it in the breech, terminating
in hemisphere. The forward part of the
bore, the chase, receives the she'll in load
ing, unites with the chamber by segment
of sphere, and is called the seat of the
she'll. From thence to the mouth of the
bore is cylindrical, and is called the "va-
cant cylinder"
MORTAR CARRIAGES OR BEDS.
For mortars which have their trunnions on
the second reinforce, the so-called hanging
mortar, the carriage consists Of two checks,
connected by bolts and transoms, but these
are now little used the carriage mostly used
is, q short massive block of wood, seasoned
aok is the best-upon this bed is followed.
out the place for the trunnion bed and the
foot of the mortar The lower corners of the
bed are notched in, to allow Of handspikes
being thrust under for moving it upon the
platform. On the trunnion of the mortar
an index is fixed, which shows upon cir
cular scale, attached to the bed, the angle
of elevation.