IMPROVEMENTS IN MOUNTING & FITTING SHIPS' GUNS & OTHER ORDNANCE
Year: 1861

page_text: PROVISIONAL SPECIFICATION left by James Alfred Limbert at the Office.
of the Commissioners of Patents, with his Petition, on the 18th June-
1861.
I, JAMES ALFRED LIMBERT, of Woodville Terrace, Gravesend, in the County
of Kent, Engineer, R.N., do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN MOUNTING & FITTING SHIPS' GUNS & OTHER ORDNANCE," to
be as follows:-
I mount ships' guns on a pivot or cross bearing placed above the gun, from.
which it is suspended, & free to oscillate in the direction of its length. From:
the bearing depend four rods, two on each side of the gun, each pair spreading
the one towards the muzzle, & the other towards the breech of the gun. The
lower ends of the depending rods carry sliding pieces fitted to arcs fixed to or
formed on the sides of the gun, such arcs being described from a contre more
or less below the gun. The suspending bearing is supported from the lower
part of the gun carriage by two wrought-iron uprights, and such stays as are
necessary. These uprights are in or about the same lateral vertical plane as
the suspending rods, and have surfaces of abutment and contact for the sliding
pieces carried by such rods, & sliding in the arcs. The effect of recoil on a
gun so suspended and fitted is, that it oscillates to the extent permitted by
the suspending rods when contact of the sliding pieces takes place, the
oscillation causing them to move in the arcs disposed (one on each side)
before the point of suspension, which has the effect of raising the gun con-
siderably at the muzzle, bringing the the weight thereof to bear in opposition

page_text: to the force of oscillation. The opposite oscillation is similarly counteracted
by the suspending rods or ares (behind the point of suspension), which has
the effect of raising the breech, and of course depressing the muzzle. The
weight of the gun, or a great part thereof, being brought to bear alternately
in opposite directions on the oscillation of the gun, it is quickly brought to
a state of rest, & this, while at same time obviating all recoil of the gun
carriage, rendering such arrangement of guns well adapted for guns secured
by pirots at the portholes. In addition to obviating the recoil of the gun
carriage, they are adapted for working through portholes of very moderate
opening in height, inasmuch as the depression and elevation of the muzzle
produced by the oscillation consequent on the recoil is very limited, while at
same time the arrangements for elevating & depressing in order to point the
gun (effected by the suspending rods in such manner as will be herein-after
explained), are such that the necessary elevation and depression are obtained
with a porthole of more limited opening in height than is required for an
ordinary gun of same size. In the foregoing description the suspending rods
in the rear of the oscillating bearing I have described as being two in number,
one on either side of the-gun, which is the case at the lower part, but above
they bridge over the gun, & are united as one piece. I connect this bridge to
the bearing by a screw, by which I am enabled to lengthen or shorten such
suspending rods, & so elevate or depress the gun. The pieces on which the
are slots are formed may also form sliding surfaces to take a bearing, & keep
the gun in position sideways. The oscillating motion of the gun on the
bearing from which it is suspended is further of advantage in counteracting
the rolling motion of the ship in a limited degree, & so maintaining a better
aim while firing. I mount my gun carriage on five wheels, one immediately
under the fore part of the gun; at the fore part of the carriage two others
(one on either side) are fixed to the fore part of the carriage in position to
traverse the gun, as on its porthole pivot, while the other two are at the
rear of the carriage (one on either side). The single wheel forward is mounted
on a bracket projecting on the fore part of the carriage, in which bracket it
swivels on a vertical axis, on which it can be turned to any desired angle,
according to the direction it is required to traverse, or for other purpose.
The two hind wheels are also mounted on vertical swivel axes, but in addition
to which swivel motion they also have the power of raising or lowering the
hinder part of the carriage, they having screws on their vertical axes for that
purpose. These three vertical axes have each hand levers, whereby they may
be readily turned, as desired. The effect of raising the hinder part of the
carriage is that it raises the two fixed fore wheels from the deck or other

page_text: surface, & transmits the weight of that part to the centrál wheel, & therefore
disposes the whole weight of the gun & carriage on three wheels; the fore
one may either become a pivot on which the gun may be turned for a breech
traverse, or it may be used as a wheel in effecting a muzzle traverse, by
transferring the pivot action to one of the hind wheels. The pivot action is
readily performed by turning the wheel in the transverso direction to that in
which the impelling force tends. In order to effect the traverse of a gun, I
fix a crank on the axis of one of the rear wheels, and on the top of the
swivelling or vertical axis I fit a shaft & winch handle at a convenient height
to be driven by hand. On this shaft is also fixed a crank, and I connect this
crank to that of the wheel axis by a connecting rod, which also forms an equal
lever, as it works on a pivot as a lever, and also slides on the pivot (being
slotted for that purpose) in its action as a connecting rod, & whereby the
dead points of the cranks are entirely obviated; by this means I am enabled
to work the wheel, and so traverse the gun either for a breech or muzzle
traverse, or simply for moving it from place to place by alternate muzzle &
breech traverses in the same direction, the alternation from breech to muzzle
traverse being effected simply by adopting alternately, as the pivot or centre
of motion, the wheel at front, & one in the rear, as described. The wheels
may also be all placed so as to move the gun straight in any direction.
Another part of my Invention refers to breech-loading guns, in which the
breech-piece is secured to the gun, & consists in making the screw of two, three,
or moro sections of the same pitch, but of different diameters, so that such
screw piece may be disconnected by a lesser number of turns than is necessary
if the same pitch and length of screw be applied of uniform diameter.
Another part of my Invention relates to breech-loading guns in which
metal cartridge cases are used, & which cartridge cases are withdrawn from
the breech after firing, by means of certain parts which grip the case by
reason of the explosion. Gripping pieces, according to my Invention, are
attached to the breech-closing piece, & are mounted on springs or otherwise,
so that they have a constant tendency to recede from each other. They are
received in a cavity or enlargement of the bore at the breech, which cavity is
coned at the mouth, in order to compress & enter the grippers to the parallel
part of the cavity. The internal surfaces of the grippers are serrated or
otherwise prepared, so that they hold the cartridge case by reason of the
force of the explosion. The grippers are withdrawn by the breech-piece, when
it is removed from the breech, bringing with them the cartridge case so soon
as they are free of the cavity of the breech into which they enter; they are
expanded or recede from their common centre by the action of springs or

page_text: otherwise, & liberate the cartridge case, which is further removed by hand or
otherwise. I form the cartridge cases for the most part slightly conical, with
a parallel part of a length equal to that of the grippers, the boro of the gun
to an equal extent being of the same form; by this means the withdrawal of
the cartridge case two or three inches by the grippers frees it in the bore, so 5
that it may afterwards be readily withdrawn by hand.