An IMPROVED CANNON FOR GUN BOATS
Year: 1855

page_text: ..PROVISIONAL SPECIFICATION left by Herbert William Hart at the
Office of the Commissioners of Patents, with his Petition, on the 6th
October 1855.
I, HERBERT WILLIAM HART, of Birmingham, in the County of Warwick,
Gunmaker, do hereby declare the nature of the said Invention for "An
IMPROVED CANNON FOR GUN BOATS" to be as follows:-
My Invention consists in constructing a cannon to be used at a long range
in gun boats in two parts (by dividing the breech from the barrel), of sufficient
length, and of such calibre in the bore, as to enable shot to be discharged
therefrom of such weight and size as will facilitate and assist in the destruc-
tion of fortified places.
'
The breech and barrel of the cannon is to be formed of laminated steel,
each thickness twisted spirally, and welded together, and every layer coiling
contrariwise; that is to say, one coil of metal is run to the left, whilst the
second coil covering, the first is to run to the right, and so on, till sufficient
thickness of metal is obtained by which means I give such strength to the
material as to render, it more durable and secure in use, whilst the cannon,
being-made to move freely by a circular end at the back of the breech,
which works in a corresponding socket, will admit of its easy elevation and
depression by means of a series of levers put in motion by the steam machinery
"

page_text: of the vessel. The bed or standard having the socket wherein the cannon
moves upwards and downwards, is firmly bolted to the deck, thereby causing the
vessel to rebound instead of the cannon after the discharge of the projectile.
Another feature of my Invention to prevent accidental explosion is the moving
forward and separating the barrel from the breech, so as to allow of the
cannon being well cleaned out after firing, and easily reloaded at the breech,
by allowing the charge of powder and shot to be raised upon a moveable
platform from below the deck to the level of the chamber of the breech whilst
the two parts of the cannon are separated. This I perform by means of a
series of toothed wheels gearing into racks. The rotation of the upper one of
three toothed wheels, gearing into a horizontal rack fixed beneath the moveable
frame supporting the barrel, put in motion by suitable means in connection
with the steam engine of the vessel, carries forward the barrel, whilst the lower
wheel, actuated by the upper and middle wheels, at the same time elevates a
vertical rack, carrying with it a platform supporting the charge of powder
and shot upon the top to the level of the chamber in the breech..
In order that my improved cannon may be fully understood as to the way
such improvements are carried into effect, reference should be had to the
accompanying Drawings, where similar letters refer to similar parts throughout
the Figures marked thereon.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a sectional elevation; Figure 2, a top plan view; Figure 3,
a sectional front end view; and Figure 4, a back end view. A and B,
Figure 1, is the breech and barrel of the cannon; C, the circular end of
the breech; D, the standard in the socket E, of which the circular end C
moves freely; D¹ is the back bed, firmly secured by screw bolts, which
This bed
pass through the deck, and are then held fast by screw nuts.
is provided with angular grooves in the sides of a recess to receive the
standard D. F, F, are two trunnions projecting from the sides of the
circular end C; upon these are fixed, by means of keys, two coupling
plates G, G, carrying the friction roller H, which works freely in suitable
brasses at the ends I, I, of the coupling plates G, G. This heavy friction
roller with the coupling plates G, G, is intended to assist partly as a counter-
poise in the elevation of the cannon. J is the front bed, lying on the deck of
the vessel and attached to the standard D; this bed moves upwards and down-
wards, as the elevation and depression of the cannon is required, by means of
the strong hinge joint K; the front bed J supports a sliding frame L, upor
which rests the barrel of the cannon; the front bed and sliding frame are held

page_text: securely together by the latch bolts M, M, beneath. At the end of the sliding
frame L rises an abutment N, which bears firmly against the mouth, and fixes
the barrel of the cannon securely on the. breech. This abutment is bored a
shade larger than the chamber in the barrel, and is externally of the same
size as the end of the barrel of the cannon, to which it, forms a lengthening
piece.
Having now described the several parts of my improved cannon, I will now
proceed to explain the means I use to load, elevate, and depress the cannon.
They are as follows:-Beneath the deck of the vessel are fixed two horizontal
levers O, O; these levers are supported and .move. in plummer blocks, and
upon their ends are connected the vertical levers P, P, and Q, Q. The upper
ends of the two levers P, P, move on the axis of the friction roller H, between
the coupling plates G, G, and the sides of the friction roller, and the upper
ends of the two levers Q, Q, move on an axis passing through the front bed J.
Upon the centre of the axis supporting the levers 0, 0, moves the arm R, the
upper end of which is formed as a circular ring, within which works a collar
R' upon an axis, having upon its inside a thread which works into and
corresponds with that of the thread. of the screw upon the end of the horizontal
rod S. Beneath the deck is formed the charge chamber T, one side of which
is in a vertical line with the face of the breech; within this chamber is made
to move upwards, by means of a vertical rack V gearing into the toothed
wheel V', a bracket, bearing on the top a platform, which carries with it the
charge up to the bottom of the chamber in the breech,, into which it is
removed.
5. That the cannon may be cleaned and the charge rise to its proper height,
the latch bolts M, M, must be withdrawn, which liberates the sliding frame L
from the front bed J, and allows the barrel of the cannon to be separated from
the breech; this separation is effected by motion being given to the toothed
wheel U, which carries forward the horizontal rack W, attached beneath the
sliding frame L. To put in action the several parts of the machinery, it is
only necessary to cause the horizontal rod S to revolve, which revolution may
be effected by a clutch fixed on the end of the rod S nearest the engine; the
teeth on the face of such clutch lock into those of another clutch worked
by the engine. This latter clutch is to be suitably mounted, and provided with
5 the well-known joints necessary to cause the rod S to revolve and retain its
horizontal position. Upon giving revolution to the rod S (if the cannon is to
be elevated from the horizontal position it rests in), the arm R will be brought
forward by the collar R¹ traversing up the screw, which will raise the levers
0, 0, and Q, Q, and.carry with them upwards the front bed J and sliding

page_text: frame L to the required. height that the cannon' is to be elevated, whilst a
reverse motion being given to the rod S will cause the cannon to be again
depressed to its horizontal position. The revolution of the rod S. is also
intended to elevate the: sight staff.X at the same time the cannon is elevated;
this is done by sliding the loose pinion ✗' on the key X" fixed on the side of
the rod till it gears into the small rack X on the side of the sight staff,
which will cause it to rise to the required: height, so as to agree with the
pointing of the cannon...
To run the barrel B and sliding frame.L.forward.after the discharge of the
cannon-for the purpose of cleaning and reloading, the latch bolts M, M, are
to be first withdrawn; the toothed wheel U, which is in connexion with the
machinery of the engine, is to be caused to. revolve and gear into the rack. W,
which will draw forward-the-sliding frame.L.to, the extent required; the wheel
U at the same time giving motion to the wheels U¹ and V, will raise the rack
Vand carry with it the lifting bracket and platform with the charge upon it
to the level of the chamber in the breech; a reverse motion being given to
the wheel U, will carry back the barrel and the sliding frame, as well as the
rack which carries the platform.and charge, upwards to their original position.
And I would here remark, that although in. this the Provisional Specification
of my shid Invention I have referred to: certain. Drawings accompanying the
same to assist the description thereof; I. do not by any means intend to limit
or confine myself. to the precise details exhibited by such said Drawings, but
réserve to myself such modifications: in the construction as. I. may find
expedient or necessary for carrying out my said Invention in the best manner.
I am acquainted with, and as will be hereafter, fully described in the final
Specification of my said Invention.