IMPROVEMENTS IN CLOSING AND OPENING PORT HOLES AFTER THE FIRING OF GUNS, AND IN THE MEANS EMPLOYED THEREFOR, THE SAME BEING IN PART APPLICABLE FOR RAISING SHIELDS TO PROTECT GUNS WHICH ARE FIRED FROM SITUATIONS OTHER THAN PORT HOLES, AND FOR DRAWING OUT GUNS AFTER BEING FIRED
Year: 1876

page_text: LETTERS PATENT to Robert Catanach Smith, of Edinburgh, in the County of
Mid Lothian, North Britain, Engineer and Ironfounder, for the Invention of
"IMPROVEMENTS IN CLOSING AND OPENING PORT HOLES AFTER THE FIRING
OF GUNS, AND IN THE MEANS EMPLOYED THEREFOR, THE SAME BEING IN PART
APPLICABLE FOR RAISING SHIELDS TO PROTECT GUNS WHICH ARE FIRED FROM
SITUATIONS OTHER THAN PORT HOLES, AND FOR DRAWING OUT GUNS AFTER
BEING FIRED."
Sealed the 19th December 1876, and dated the 24th June 1876.
PROVISIONAL SPECIFICATION left by the said Robert Catanach Smith at the
Office of the Commissioners of Patents on the 24th June 1876.
ROBERT CATANACH SMITH, of, Edinburgh, in the County of Mid Lothian, North
Britain, Engineer and Ironfounder. "IMPROVEMENTS IN CLOSING AND OPENING
PORT HOLES AFTER THE FIRING OF GUNS, AND IN THE MEANS EMPLOYED THEREFOR,
THE SAME BEING IN PART APPLICABLE FOR RAISING SHIELDS TO PROTECT GUNS
WHICH ARE FIRED FROM SITUATIONS OTHER THAN PORT HOLES, AND FOR DRAWING
OUT GUNS AFTER BEING FIRED."
This Invention, which in part relates to improvements in closing and opening the
port holes of ships, forts, batteries, and other situations wherein guns are employed,
has for its object to protect the gunners whilst in the act of reloading the guns from
fire directed against the port holes.
This object is effected by means of shutters, doors, shields, or their equivalents
placed either at the inner or outer side of the port holes and which are operated
vertically, horizontally, or through a circle or are so as to close the port holes
immediately after the guns have been fired and run in to be reloaded. The doors,
shutters, or shields so employed may be flat, but it is preferred to make themi
hemispherical or curvilinear on their outer sides, or each door, shutter, or shield
may be composed of a ball or sphere of sufficient size to entirely close the port
hole when moved into position as herein-before set forth.
The doors, shutters, or
shields are shot proof, and they are connected to the gun carriage by levers, ropes,
chains, or the equivalent thereof, so that as the guns recoil on the instant of firing
he doors, shutters, or shields are either raised or lowered, moved sideways or swung
ound so as to close over the port holes. The said apparatus when the gun is
gain run out is caused to open the port hole by virtue of the gun carrriage
[Price 6d.]

page_text: moving in the opposite direction, and the weight of the port shutter when being
lowered helps to draw out the gun.
The arrangement of levers or other equivalent mechanism for opening and closing
the doors, shutters, or shields instead of being connected to the gun carriages as
herein-before described may be connected to any suitable prime mover, under the
control of the gunners by actuating which the doors, shutters, or shields are opened
and closed when desired.
In order to more effectually fix the port shutters over the ports they are provided
with electro or other magnets, which at the time the shutter is over the port
hole attract it towards-an-insulated plate against which the port shutter bears or
rests.
When the gun is not fired through a port hole the gun carriage is connected to
toggle jointed levers or the equivalent thereof, which as the gun recoils being
pulled backwards raise a shield into an inclined position in front of the gun and so
untest it and the ounners.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said, Robert Catanach Smith in the Great.Scal, Patent Office-on-the 23rd
December 1876.
ROBERT CATANACH SMITH, of Edinburgh, in the County of Mid Lothian; North
IMPROVEMENTS IN CLOSING AND OPENING
Britain, Engineer and Ironfounder.
PORT HOLES AFTER THE FIRING OF GUNS, AND. IN THE MEANS EMPLOYED THEREFOR,
THE SAME BEING IN PART. APPLICABLE. FOR RAISING SHIELDS TO PROTECT GUNS
WHICH ARE FIRED FROM SITUATIONS OTHER THAN PORT HOLES, AND FOR DRAWING
OUT GUNS AFTER BEING FIRED."
*li.
My said Invention, which relates to improvements in closing and opening port
holes of ships, forts, batteries, and other situations wherein guns are employed, has
for its object to protect the gunners whilst in the act of reloading the guns from
fire directed against the port holes. This object is effected by means of shutters,
doors, shields, or their equivalents, placed either at the outer or inner sides of the
port holes, and operated vertically, horizontally, or through a circle or arc, so as to
close the port holes immediately after the guns have been fired and run in to be
reloaded.
I
:
And in order that my said Invention may be properly understood, I now proceed
more particularly to set forth the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, reference being had to
the annexed Sheets of Drawings and to the letters and figures thereon, that is to
say:
On Sheet 1 of the Drawings hereunto annexed Figures 1 and 2 illustrate in
vertical section and Figure 3 in horizontal section one arrangement under which
my said Invention may be carried into practical effect, and as shewn by these
Figures a shutter, door, or shield A is placed between guides D at the outside of the
port hole B, and suspended in position by means of chains or ropes C attached to
its inner side. These chains or ropes after passing under or round pulleys suitably
situated are also attached to the gun carriage either at the rearward or forward
end thereof, so that as the gun E recoils on the instant of firing, the door, shutter
or shield A is raised from the position shewn at Figure 2 into that shewn at
Figure 1, so as to close over the port hole and protect the gunners from fire
The door
directed against the port holes whilst in the act of reloading the gun.
shutter, or shield, when the gun is again run out moves downwards into the position
shewn at Figure 2, and so opens the port hole, the weight of the said door, shutter
The chains C are so connected to the gu
or shield helping to draw out the gun.
carriage that they act with an equal pull or strain at both sides or ends of th
door, shutter, or shield A in all positions of the gun carriage upon its slides, that i

page_text: to say, in every position to which the gun is adjusted in order to fire in a direction
diverging to the right or left from the centre of the port hole B. The connexions
between the chains C and the gun carriage are or may be effected by slip clutches,
so that in the event of the recoil of the gun not being expended at the instant
when the door, shutter, or shield has been raised to its highest position the chains
inay slip through the clutches, and thereby be prevented from undue strain or from
breaking, or any other equivalent arrangement of mechanism may be employed
for this purpose.
Figures 4 and 5, Sheet 1, of the Drawings illustrate in vertical section the closed
and open positions respectively of another arrangement of the door, shutter, or
shield A, and of mechanism for operating the same. Under this modification the
door, shutter, or shield A, which moves through an arc in a vertical plane, is con-
nected to levers B. The levers are centred at C, and chains connected to rollers or
pulleys D pass in the direction of the arrows round similar rollers or pulleys
carried in the lower ends of the levers B, from whence the said chains are con-
ducted to the gun carriage, and connected in the manner herein-before described
or in a manner analogous thereto. With this arrangement when the gun recoils on
the instant of firing the lower extremities of the levers B are depressed and drawn
towards the rollers or pulleys D, thereby raising or elevating the door, shutter, or
shield into the position shewn at Figure 4, and so closing the port hole.
By making the connexion between the door, shutter, or shield A and the levers B
nearer to the upper end of the door than is shewn on the Drawings, the door when
in its lowered position may be made to hang vertically in lieu of lying horizontally,
as seen at Figure 5.
Figure 6, Sheet 1, of the Drawings, illustrates another modification under which
my said Invention may be carried out in practice. With this arrangement the door,
shutter, or shield A is provided with a hinge B at its upper end, on which when
the gun is about to be run out the door or shield is turned upwards so as to leave
the port hole open. This upward movement is effected by connecting the door to
one end of a lever B¹, to whose opposite extremity one end of a chain C is attached,
the said chain being passed round pulleys D, to an hydraulic, steam, or compressed
air cylinder E, at one end of which the opposite end of the chain is attached after
passing in the direction of the arrow round a pulley F, carried in the outer end of
the piston rod of the said cylinder. By this arrangement, after the gun has recoiled
the door, shutter, or shield is lowered by releasing the pressure at the side ✗ of the
piston in the cylinder E, and allowing the door to move downwards by its own
weight, and when the gun after being reloaded is about to be run out through the
port hole previous to being again fired, the door, shutter, or shield is raised by
readmitting water, steam, air, or other gas or fluid under pressure to the end X of
the cylinder E.
Instead of hinging the door, shutter, or shield A, so that in opening it moves
through an are upwards, the said door may be so hinged as to move through an arc
downwards when opening, in which case the chains C may if desired be connected
to the gun carriage instead of to the cylinder E, and instead of connecting the
chains which operate the doors, shutters, or shields in the modifications herein-before
described to the gun carriage, they may be connected to hydraulic or other cylinders
for the purpose of closing them after the gun has been fired and has recoiled. When
an hydraulic or air cylinder is employed to operate the doors, shutters, or shields,
in any of the modifications herein-before described the recoil of the gun may be
utilized to exert the pressure on the water or air necessary to give it the force
requisite for closing or opening the door, shutter, or shield.
Under another modification illustrated in elevation at Figures 1 and 2, and in
horizontal section at Figure 3, Sheet of the Drawings, the door, shutter, or shield
s so hinged at its lower end as to move sideways over the port hole B in the act
of closing it. The pin C which serves as the hinge for the door A is provided
t its inner end with a lever D, to which a chain or rope E is attached, the said
chain being also connected to the gun carriage or to an hydraulic or other cylinder

page_text: as herein-before set forth, for the purpose of closing the door, shutter, or shield over
the port hole whilst the gun is in the act, or after it has recoiled. The hinge is
preferably placed to one side so that when the gun is being again run out or when
the pressure on the hydraulic or other cylinder operating the chain has been released
the door, shutter, or shield may slide downwards of its own accord in the direction
of that side which has the greater weight, or instead of this arrangement the hinge
or pin C may be placed at the lower central part of the door, and an additional
chain connected to an hydraulic or other cylinder employed to open the port B when
desired. The lever D is or may be formed with a catch or enlargement on its lower
end which acts against studs so as to prevent the door, shutter, or shield from
moving too far in any direction, or a catch or analogous arrangement may be attached
to the door itself for that purpose.
Under another modification shewn in horizontal section at Figure 4, Sheet 2 of the
Drawings, the door, shutter, or shield A is connected at its upper and lower ends to
levers B, which are slotted to receive pins or studs C, fixed in the upper and under
parts of the port hole. The rearward end of each lever is connected by a chain D
with the piston of an hydraulic or other cylinder, which by releasing the strain upon
the chains after each firing of the gun allows the door, shutter, or shield to swing
round from the position shewn in dotted lines into that shewn by the firm lines,
thereby closing the port hole. With this arrangement a rectangular port hole is
used, the sides or ends X of the door, shutter, or shield being parallel. Instead of
employing in this modification a door, shutter, or shield, oval or elliptical in
horizontal section as shewn on the Drawings, a door, shutter, or shield whose
horizontal section is circular, rectangular, or of other suitable form may be so used.
In order to more effectually fix the port shutters over or against the ports,
electro or other magnets are or may be provided which at the time the shutter is
over the port hole attract it towards an insulated plate or insulated plates as seen
at X, Figure 7, Sheet 1 of the Drawings. The shutters are or may also in some
instances be provided with an india-rubber or other elastic cushion at their inner
sides as seen at a¹, Figure 3, Sheet 2, in order to lessen the shock when raising,
lowering, or otherwise closing them over the port holes.
When the gun is fired through an embrasure or when employed in field or siege
operations, en barbette, the gun carriage is connected to toggle jointed levers or the
equivalent thereof, which as the gun recoils, being pulled backwards, raise a
shield into an inclined position in front of the gun so as to protect it and the
gunners. This arrangement is illustrated at Figure 5, Sheet 2, whereon the toggle
jointed levers A of the slutter B are shewn connected to chains C, these being
either attached to the gun carriage, in the manner herein-before set forth, or in an
analogous manner or to an hydraulic or other cylinder as described with reference
to Figure 6, Sheet 1 of the Drawings.
Figure 6, Sheet 2, illustrates another modification of my said Invention, and
under this arrangement. a ball or sphere A is attached by a chain or rope B to
the gun carriage or to an hydraulic or other cylinder in order to close the port
hole, as and for the purpose. herein-before described. When attached to the gun
carriage the shutter A is lowered from. the port hole in the act of running out the
gun and it descends and ascends on the curved or inclined plane C. At its lowest
position the shutter A is under cover.
Under another modification of any said Invention not shewn on the Drawings
the shutters, doors, or shields, may be closed over the port holes by the carriage
when recoiling, acting on the free end or ends of a lever or levers which is or are
connected to the shutter. .In this case the gun itself acts as a counterpoise weight
to the door, shutter, or shield, and maintains it in its closed position, or the closing
and opening of the various modifications of the shutter, door, or shield may be
facilitated by a counterpoise specially provided for that purpose.
The shutters, doors, or shields in the several modifications herein-before referred
to may be made of malleable.iron, but it is preferred to construct them of cast
steel, chilled cast iron, phosphor bronze, or other similar material, in order the

page_text: better to render them shot proof, and they may be so fitted to the port holes as
in the event of receiving damage to be capable of being detached and replaced.
An object of the Invention is to form the contour of the shields, shutters, or doors
80 as to present the least possible surface at right angles to any line of fire,
and this effected by forming them with their outer surfaces curved, inclined, or
bevilled to an angle, though when desired the said doors, shutters, or shields may
also have their outer surfaces flat as shown by several Figures of the appended
Drawings.
Having now described and particularly ascertained the nature of my said
Invention, and several modifications in or under which the same is or may be used
or carried into practical effect I desire to observe in conclusion that I do not confine
myself to the precise arrangements herein-before described, and dilineated on the
accompanying Drawings as the Invention is capable of being further modified
without departing from the main or essential features, of my said Invention. What
then I consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent is―
First. Closing port holes after the firing of guns and so as to protect the gunners
whilst reloading by means of doors, shutters, or shields, constructed and operated
as herein-before described, with reference to Sheets 1 and 2 of the Drawings, or any
mere modification of such arrangements.
Second. The arrangement herein-before described and shewn at Figure 5, Sheet
2 of the Drawings, for protecting the gunners whilst reloading in batteries, forts,
field works, and other situations wherein the guns are fired en barbette or any
mere modification thereof wherein a shield connected to toggle jointed or equivalent
levers is by the recoil of the gun or by a prime mover especially provided for that
purpose raised into an inclined position, substantially as herein-before described.
Third. Fixing the port doors, shutters, or shields in their closed positions by
means of electro or other magnets and insulated plates, substatially as herein-before
described, with reference to Figure 7, Sheet 1, of the accompanying Drawings.
In witness whereof, I, the said Robert Catanach Smith, have hereunto set
my hand and seal, this Twenty-first day of December, One thousand eight
hundred and seventy-six.
ROBERT CATANACH SMITH. (L.S.)