Year: 1887

page_text: T, DAMES
Community 21.
declare the nature of this invention to be as follows:-
The nature of my invention relates to a new form of telescopic sight for field and
heavy ordnance and to a new method of arranging the sighting mechanism so that
the speed and accuracy of gun fire may be materially increased.
"
It is worked in the following manner. The gunner or person aiming the gun, on
being told the distance or range of the object, at which he is to fire revolves a range
wheel till the figures on its periphery corresponding with that distance meet the knife
edge of a locking arm. This action gives motion to a wheel on whose circumference
a cam groove is cut which is a projection of the "drift" curve of the gun at all ranges
by a pin or stud working in this groove as the wheel is revolved motion is given to a
drift slide, deflecting it laterally-and through it the telescope exactly the amount
The wheel also through
necessary to allow for "drift" at any required range.
suitable gearing causes an "elevation bar to assume the exact angle (practically
ascertained) at which the gun if fired will carry the required distance under normal
conditions. Attached to this bar is a parallel motion which when the gun assumes
its correct elevation completes electrical circuit by means of a "contact plate" moving
automatically with the gun or its cradle or carriage becoming parallel to the
"elevation bar," the arrangement then, may be such that the elevating or depressing
of the gun is at once stopped or a signal bell may be rung to tell those who are
working the elevating machinery when to stop, or a galvanometer or other electrical
or mechanical device may be adopted, which, actuated by electrical contact in the
manner described or in any other way by means of the "range wheel" and
elevation bar," or any adaptation or modification of them will control and regulate
the working of the gun and indicate its arrival when being trained at the proper
position in the vertical plane when it may be fired automatically.
In the case of two guns working together in a turret or barbeite, the position of
the person sighting might in the first case be over and between, and in the latter in a
ower position but also between the guns.

page_text: For the guidance of those working the guns which operation may be carried on
altogether out of sight of the weapon provide a galvanometer or "indicator"
which shows on a dial whether the gun requires to be raised or lowered too much
will by reversing the direction of the current, deflect a needle and so instruct the
operators.
Attached to the ends of the pendant arms of the "parallel motion" is an arrange-
ment whereby the circuit may be completed slightly before the proper time, so that
any correction or variation required in the elevation of the gun from any cause may
be given by slightly lengthening or contracting one of the arms.
"
"
In the case of aiming at an object in motion, say a ship steaming at any rate of
speed, in any direction, my invention provides automatically for any alterations in
elevation or deflection due to the speed of the ship aimed at. This is done in the
following manner. The motion of the "range wheel" in doing what I have already
described also actuates two "cams" of double curvature, these while ülting a
tangent bar" until it becomes tangential to a converse "curve of elevations" of the
gun in the vertical plane, at the same time move it sideways till it becomes in liko
manner tangential to the converse
"drift curve 2:
in the horizontal plane; meanwhile
the gunner pointing and clamping a speed slide" in the direction in which the
object of attack is heading; the motion of the point of this slide is transmitted to
the telescope and gives it any required alteration, first in deflection right or left,
secondly in elevation lessened or increased, thirdly it rearranges the normal
drift, already given by the grooved wheel as described, to suit the require-
ments of decreased or extended range as the vessel aimed at sails towards or from the
firer. Any alteration from the normal sighting of the gun due to the forece und
direction of the wind is given by a graduated slide moving in one of two concentric
circles, which are suitably figured and of which one is stationary the other revolving
within it and being clamped in a position indicated by the direction from which the
wind is blowing, compels the slide and through it the telescope to move in a direction
which is the resultant of the forces of deflection and elevation or depression due to
the force and direction of the wind.
The following is a description of the principle on which it works.
In a strong breeze and under normal conditions as to sighting, if a gun he fired at
a mark or "bulls-eye," on a vertical plane or target and if the firing be continued
while the wind keeps changing its direction all round the clock or compass, without
altering its force, the shots will hit the target in the circumference of a large ellipso
whose centre would be the mark aimed at, whose major axis (horizontal) would be
deflection right plus deflection left, whose minor axis (vertical) would be depression
from a 12 o'e wind plus elevation from a Go'e wind, and if while hitting any place in
the circumference of this ellipse a line be drawn from that spot to the centre or
"bulls-eye," the wind calming down and the firing kept up, the points of impact
of the shots would be on this line gradually approaching the centre till finally if the
breeze subsided altogether they would hit the centre of the mark aimed at. It will
be seen that the size of the ellipse depends on the force of the wind and consequently
every force of wind has its own ellipse, that they have a common centre and axes,
that they are similar in shape, and that if a lino be drawn from the centre to any
point in their circumference this line will be the resultant of deflection and elevation
allowances due to a certain "force and direction" whose correct amount could be
measured in the usual way by the parallelogram of forces, but in my invention are
compensated for by deflecting along the line of this resultant and so effecting on the
eye piece of the telescope a converse reproduction, on a very small scale, of the large
ellipse described by the point of impact of the shots.
In the case of permanent "heel" or "dip" or if from any cause the gun platform
be out of level, or not in the exact horizontal plane, I provide, to remedy this, a
wheel operating on a vertical elevating screw by which the sighting telescope
is adjusted so that its cross wires will cut the object or the part of it required to
be bit.
The electrical and other mechanisms are in no way effected by any condition of

page_text: this kind the gun may be placed in; they are also uninfluenced by the recoil of the
gun or guns.
For the purpose of extreme accuracy or if firing at a long range, the telescope has
affixed to it a small spirit level, at right angles to its line of collimation its bubble is
reflected so as to be seen in the telescope tube by the person using it.
The telescope is mounted on a light steel bar or beam working at its remote end on
a forked bearing or universal joint, so that no matter how it is moved, its optical axis
will always cut a point in the centre of its hearing any length from the eye piece
represented by the bar, and corresponding to their distance apart if ordinary sights
were used.
For field artillery purposes where the platform, from which the guns are fired,
may be out of level, or for guns of any nature or description on shipboard or other-
wise liable to either permanent or variable inclination of the plane from which they
are fired I use a form of my invention which can be instantaneously adjusted so
that the necessary correction in level can be made and proper elevation given to the
gun, this is effected by making the lower end of the tangent sight an arc of a circle
of a certain diameter suitable to the requirements of the gun, this are moves in
grooved bearings from which it can be readily detached and which enable it at all
times to be placed in a vertical position shewn by a spirit level attached to the sight.
The tangent bar has the ordinary scales marked in yards of range and in degrees of
elevation and has an affixed "Drift Fin" curved to a certain form so that if the sight
is elevated the exact drift deflection is automatically allowed for by a wheel or rubber
working against the edge of the "Fin," and which moving a slide compels a telescope
or orthoptic eye-piece or a back sight of any description to move in the exact drift
of the piece; affixed to the slide is a segmental curve which moving freely round it,
and which when being used is made to assume the inclinations, before described, due
to the directions of the wind or the directions of the moving body fired at, if used
for that purpose. Working in the carrier is a slide in which is fixed the telescope
eye-piece or other description of back sight which may be used and whose motion is
regulated in the manner described.
Dated this 1st day of November 1887.

page_text: Improvements in Sighting Appliances for Ordnance.
I, JAMES O'KELLY, Journalist, M.P., 65 Bessborough Street, S.W., do hereby
declare the nature of this invention and in what manner the same is to he
performed to be particularly described and ascertained in and by the following
statement:
The nature of my invention relates to a new form of telescopic sight for field and
heavy ordnance and to a new method of arranging the sighting mechanism so that the
speed and accuracy of gun fire may be materially increased.
It is worked in the following manner. The gunner or person aiming the gun, on
being told the distance or range of the object at which he is to fire, revolves a range
wheel till the figures on its periphery corresponding with that distance meet the knife
edge of a locking arm. This action gives motion to a wheel on whose circumference
a cam groove is cut which is a projection of the "Drift" curve of the gun at all
ranges by a pin or stud working in this groove as the wheel is revolved motion is
given to a Drift slide, deflecting it laterally and through it the telescope exactly the
amount necessary to allow for "Drift" at any required range. The wheel also
through suitable gearing causes an Elevation bar" to assume the exact angle
(practically ascertained) at which the gun if fired will carry the required distance
under normal conditions. Attached to this bar is a parallel motion which when the
gun assumes its correct elevation completes electrical circuit by means of a
plate" moving automatically with the gun or its cradle or carriage becoming parallel
to the
Elevation har," the arrangement then, may be such that the elevating or
depressing of the gun is at once stopped, or a signal bell may be rung to tell those
who are working the elevating machinery when to stop, or a galvanometer or other
electrical or mechanical device may he adopted, which, actuated by electrical contact
in the manner described or in any other way by means of the "Range wheel" and
Elevation bar," or any adaptation or modification of them will control and regulate
the working of the gun and indicate its arrival when being trained at the proper
position in the vertical plane when it may be fired automatically.
.1
"
contact
In the case of two guns working together in a turret or barbette, the position of
the person sighting might in the first case be over and between, and in the latter in
a lower position but also between the guns.
For the guidance of those working the guns which operation may be carried on
altogether out of sight of the weapon I provide a galvanometer or "indicator" which
shows on a dial whether the gun requires to be raised or lowered.
i.
Attached to the ends of the pendant arms of the parallel motion " is an arrange-
ment whereby the circuit may be completed slightly before the proper time, so that
any correction or variation required in the elevation of the gun from any cause may
be given by slightly lengthening or contracting one of the arms.

page_text: "
<<
In the case of aiming at an object in motion, say a ship steaming at any rate of
speed, in any direction,-my invention provides automatically for any alterations in
elevation or deflection due to the speed of the ship aimed at. This is done in the
following manner. The motion of the " range wheel" in doing what I have already
described also actuates two cams of double curvature, these while tilting a tangent
bar until it becomes tangential to a converse curve of clevations of the gun in
the vertical plane, at the same time move it sideways till it becomes in like manner
tangential to the converse << drift curve in the horizontal plane; meanwhile the
gunner pointing and clamping a "speed slide" in the direction in which the object
of attack is heading; the motion of the point of this slide is transmitted to tho
telescope and gives it any required alteration, first in deflection right or left,
secondly in elevation lessened or increased, thirdly it rearranges the normal drift,
already given by the grooved wheel as described, to suit the requirements of decreased
or extended range as the vessel aimed at sails towards or from the firer. Any
alteration from the normal sighting of the gun due to the force and direction of the
wind is given by a graduated slide moving in one of two concentric circles, which
are suitably figured and of which one is stationary the other revolving within it and
being clamped in a position indicated by the direction from which the wind is
blowing, compels the slide and through it the telescope to move in a direction which
is the resultant of the forces of deflection and elevation or depression due to the
force and direction of the wind.
In the case of permanent "heel" or "dip" or if from any cause the gun platform
be out of level, or not in the exact horizontal plane, I provide, to remedy this, a
wheel operating on a vertical elevating screw by which the sighting telescope is
adjusted so that its cross wires will cut the object or the part of
be hit.
required to
The electrical and other mechanisms are in no way affected by any condition of
this kind the gun may be placed in; they are also uninfluenced by the recoil of the
gun or guns.
The telescope is mounted on a light steel bar or beam working at its remote end
on a forked bearing or universal joint, so that no matter how it is moved, its optical
axis will always cut a point in the centre of its bearing any length from the eye-
piece represented by the bar, and corresponding to their distance apart if ordinary
sights were used.
For field artillery purposes where the platform, from which the guns are fired, may
be out of level, or for guns of any nature or description on shipboard or otherwise
liable to either permanent or variable inclination of the plane from which they are
fired, I use a forin of my invention which can be instantaneously adjusted so that the
necessary correction in level can be made and proper elevation given to the gun,.
this is effected by making the lower end of the tangent sight an arc of a circle of a
certain diameter suitable to the requirements of the gun, this are moves in grooved
hearings from which it can be readily detached and which enable it at all times to
be placed in a vertical position shown by a spirit level attached to the sight. The
tangent bar has the ordinary scales marked in yards of range and in degrees of
elevation and has an affixed "drift fin" curved to a certain forin so that if the sight
is elevated the exact drift deflection is automatically allowed for by a wheel or rubber
working against the edge of the "fin," and which moving a slide compels a telescope
or orthoptic eye-piece or a back sight of any description to move in the exact drift of
the piece affixed to the slide is a segmental curve which moving freely round it,
and which when being used is made to assume the inclinations before described, due
to the directions of the wind or the directions of the moving body fired at, if used for
that purpose. Working in the carrier is a slide in which is fixed the telescope eye-
piece or other description of back sight which may be used and whose motion is
regulated in the manner described.
In order that my invention may be fully understood and readily carried into effect
I will proceed to describe the drawings hereunto annexed.

page_text: Figure 1 is a side elevation of sighting appliances for ordnance arranged in
accordance with my invention.
In order to avoid complication the parts which control the eye end of the telescope
are omitted from this Figure and these are shown to a larger scale by the Figures 2
and 3.
Figure 2 is a side elevation partly in section and Figure 3 is a rear elevation also
partly in section.
Figure 4 shows my invention applied in a simpler form to the tangent sight to be
carried upon the gun itself.
a is a bar carrying the telescope or it might be any other sight but usually a
telescope is to be preferred. The bar a is connected by an universal joint with the
turret or rotating platform on which the gun is carried.
When the bar moves about the universal joint the axis of the telescope remains
directed constantly to the central point (which is equivalent to a fore sight). c is
a frame jointed at its fore end to the turret in such manner that it is moveable in a
vertical plane parallel to the axis of the gun; it carries parts which support a guide
in which the rear end of the telescope is carried by a hall and socket joint. The
frame crests at the back upon the hand screw d (see Figs. 2 and 3) which is held in
a support fixed to the turntable or turret. By means of the screw d and the turning
gear of the turret the telescope can be brought to bear on the mark. The frame c
carries an axis e on which is the hand wheel called the range wheel. When it is
turned it operates through the train of gear marked g upon a quadrant forming part
of a piece which is called the "elevation bar." The elevation bar is moveable
around the same centre as the frame c.
The elevation bar is thus adjusted to a position corresponding to the elevation
normally required to be given to the gun for the range to which the range wheel is
set. The drawing (Fig. 3) shows a scale of yards graduated upon the periphery of
the range wheel. is a cam (called the drift cam) fixed on the axis e. The axis e
has bearings in a piece j moveable up and down on suitable stationary guides. When
the axis e is turned the drift cam gives a lateral movement to a slide k and the amount
of this motion is such as is normally required to compensate for the "drift" or lateral
deviation of the shot. The slide has a lever called a " tangent bar" connected
with it by horizontal and vertical pivots or joints. The tangent bar operates as
hereinafter described to effect that adjustment of the aim or alignment of the telescope
which is necessary to compensate the movement of the ship or object aimed at. The
portion of the tangent bar is regulated by means of the range wheel as follows:-
m is a pinion on the axis e with it another pinion n gears and this actuates two other
pinions. On the axis of one of these is a cam o and on the other a counter cam o'.
Thus the position of the tangent bar changes with the range. p is a foot resting
upon the tangent it is capable of being moved by a screw along the crosshead ' at
the lower end of the stem 7. The crosshead q' is called the "speed slide." The stem
carries the guide which controls the position of the telescope or other sight. It will
be seen that when the foot p is over the centre of the tangent bar it does not matter
in what way the tangent bar is inclined its position laterally is determined simply
by the drift cam in accordance with the range.
The foot p is set over the centre of the tangent bar when the target is at rest.
But if the target is in motion the foot p is moved along the speed slide q¹ more or less
in accordance with the speed of the target and as indicated by the scale shown upon
the drawing. The speed bar qis also turned to a direction parallel to that in which
the target is travelling. This it will be seen will vary both the direction given to the
telescope and the inclination in a vertical plane of the telescope and frame carrying
the range wheel. The scale is so formed and the cams are so cut that this adjustment
gives the correction needed for the movement of the target at any range.
The stem carries at its upper end a ring r and another ring s is capable of rotating

page_text: within the ring and this ring carries the slide t; on this slide is a ball and socket
joint in which the eye end of the telescope is held. The ring s and the slide t provide
means for making the adjustment requisite to compensate for wind. The wind requires
an allowance to be made for it both in direction and elevation. For this purpose the
rings is rotated to a position dependent only on the direction of the wind and as
indicated by the scale on the instrument and the slide t is then traversed a suitablo
distance also indicated by a scale on the instrument which is shown by the drawing.
Any allowance necessary for the speed of the ship itself may be taken into account
either in the allowance upon the wind scale or on the scale on which the movement of
the target is allowed for."
When the sight has been set as described the telescopo is brought to bear on the
target by means of the screw d and the rotating gear of the turret. This having
been done a signal is given to the men working the gun to adjust the elevation which
they proceed to do by the ordinary hydraulic or other gear. Now the quadrant h
already referred to carries two pendent arms (see Fig. 1) connected by a link v so
that they remain always parallel to each other. At the lower end of each arm is an
insulated contact piece with a battery connection. An adjusting screw may be
provided by which the length of one of the arms a can be slightly varied for the
purpose of adjustment. On the gun slide there is a contact plate w and one or other
of the pieces u¹ at all times rests on the plate w. When the gun comes to the proper
elevation both of the contact pieces bear and the electrical apparatus then signals
automatically that the gun bears on the target; it may then if desired be fired or the
firing may be performed automatically.
The indicator may be a needle galvanometer; the contact pieces u¹¹ may bo
connected to the terminals of a battery cach to each, whilst the contact plate on the
gun is connected through the galvanometer with the middle of the battery. Then ono
contact piece bearing gives say a right deflection of the needle and indicates that the
gun requires elevating whilst the other contact piece bearing gives a left deflection and
indicates that the gun requires to be lowered. When the needle stands in its middle
position it indicates that the elevation of the gun is that to which the sighting apparatus
has previously been set.
In Figure 4 which is an elevation of a tangent sight constructed in accordance with
my invention A is a piece fixed to the gun near the breech end B is a socket connected
with the piece A by the horizontal hinge pin A indicated by dotted lines; this joint
allows the sight to fold forward if the gun is fired with the sight in place. C is a bar
with a foot C curved to an arc of a circle; the socket which this foot enters is of
corresponding form, it allows the sight to be set vertical when the gun is standing on
uneven ground. is a fin or cam surface formed or fixed upon the side of the bar (;
this fin C is the drift cam. D is a clamping screw, E is a slider on the bar C it can
be moved up and down by hand and retained in any position by the spring catch E¹
upon it. E is an arm projecting horizontally from the slider E. F is a transverse
slide capable of movement along the arm E on it there is a spirit level F' which is
used in setting the bar C upright. F is a ring which is fixed to or forms part of the
transverso slide F. is a small wheel carried upon F it is caused to bear constantly
against the edge of the drift cam or fin C by a coiled spring contained within the
arm E and bearing against the slider F. G is a piece moveable around on the ring F
it carries four little wheels indicated by dotted lines which run in grooves on the outer
and inner edges of the ring. The piece G can pass half round the ring, its movement
is limited by the stops F* F*. The piece G is to be set according to the direction of
the wind; it is retained by a spring catch. H is a sight carrier, it has a sight hole H¹
in it or it may carry any other form of sight. The piece H can move radially to the
ring F2 and it is set by rack and pinion according to the force of the wind by the aid
of a scale marked upon it. It will be remarked that this arrangement for allowing
for wind is the same as that previously described and that in this sight also at the
same time that the elevation is given for range a lateral movement is given to the
sight to correct for drift by the aid of a cam surface of suitable curvature.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed i declare that what
I claim is
1. The arrangement for sighting ordnance consisting of an elevation bar with
suitable gearing for setting it to the elevation to be given to the gun; such elevation
bar carrying by means of parallel pendent arms two contact points to bear on a
contact plate moving with the gun when the same is elevated and which plate makes
contact with both of the contact points simultaneously when the gun is brought to the
elevation for which the elevation bar is set.
2. In sighting appliances for ordnance a drift cam operating in conjunction with
the range wheel so that by the rotation of the range wheel the sighting mechanism is
simultaneously set for range and for drift.
3. In sighting appliances for ordnance mechanism for compensating for wind
consisting of a slide controlling the back sight; such slide being capable of longi-
tudinal movement and being carried by a rotatable frame which may be so set that the
longitudinal movement of the slide takes place either in a vertical horizontal or
inclined direction as the course of the wind may require.
4. In sighting appliances for ordnance, mechanisin for compensating for the move-
ment of the target consisting of a fangent bar which is set to position by cams
operated by the range wheel and a speed slide connected with the sight; such speed
slide in setting the sight being traversed along the tangent bar to a position in
accordance with the speed and directed in accordance with the course.
5. In sighting appliances for ordnance the combination of apparatus consisting of
a frame connected by a joint with the turntable or turret on which the gun is mounted
and moveable about the joint in a vertical plane parallel to the axis of the gun; such
frame carrying an elevation bar, a drift cam, a range wheel and a sight and these
paris being so geared together that by turning the range wheel the elevation bar is
sel for range and simultaneously the sight is set for drift.
6. In sighting appliances for ordnance making the lower end of the bar of the
tangent sight an are of a circle moveable in a socket of corresponding form to admit
of the sight-bar being set to a vertical position.
7. In sighting appliances for ordnance mounting a transverse slide upon the slider
of the tangent sight and controlling the same by a cam or suitably curved guide.
8. Sighting appliances for ordnance substantially as herein described.
Dated this 3rd day of September 1888