Range Finding Sights for Guns in Elevated Positions.
Year: 1896

page_text: Date of Application, 1st Jan., 1896
Complete Specification Left, 30th Sept., 1896-Accepted, 31st Oct., 1895
PROVISIONAL SPECIFICATION.
Range Finding Sights for Guns in Elevated Positions.
We, ALBERT GEORGE HADCOCк, late R.A., and RALPH THEW BRANKSTON,
Engineer, both of Elswick Works, Newcastle-on-Tyne, do hereby declare the
nature of this invention to be as follows:-
The sights to which this invention relates are more especially applicable to
guns intended to maintain a plunging fire upon ships coming within range. The
guns are carried in cradles or rocking slides and recoil in the line of fire.
A bracket is fixed to the cradle with T headed bolts so as to be readily
removeable. The sight bar carrying the sights is pivotted near its fore end to
the bracket and about midway of its length it has an arm projecting downwards
and carrying a pin which enters a groove of the required cam like form. Or
the cam groove may be replaced by a cam surface, a spring being then provided
to keep the parts in contact. The cam is mounted upon a support attached to
the gun carriage, it may conveniently be upon the cap of the trunnion bearing,
and it is adjustable thereou to compensate any error in the platform level. The
cam is pivotted to the support and its fore end is adjustably connected therewith
by a screw which is used to compensate the rise and fall of the tide. For the
purpose of reading the range a graduated arc is provided upon the sight bar.
Another arrangement is as follows:-An arc of teeth is fixed upon the carriage
concentric with the trunnion bearing and on the cradle there is a radial axis
with a pinion engaged with the toothed arc; hence the axis rotates whilst the
cradle with the gun is being elevated or depressed. By bevilled gearing the axis
conveys movement to a toothed wheel mounted on the cradle and the wheel gears
with a sliding rack which it moves in a fore and aft direction. The rack carries
the cam which controls the sight bar as already explained. There are similar
adjustments, for height of tide and for error of platform level, the latter adjustment
being made by shifting one of the gear wheels around its axis.
Dated this 21st day of December 1895.
A. G. HADCOCK.
R. T. BRANKSTON.
We, ALBERT GEORGE HADCOCK late R.A. and RALPH THEW BRANKSTON,
Engineer both of Elswick Works, Newcastle-ou-Tyue, do hereby declare the
nature of this invention and in what manner the same is to be performed to
be particularly described and ascertained in and by the following statement :-
The sights to which this invention relates are more especially applicable to guns
intended to maintain a plunging fire upon ships coming within range. The
invention is illustrated by the drawings annexed.
Figure 1 is a side view of a gun with sights in accordance with our invention; the
gun is here shown in the horizontal position. Figure 2 is a similar view but with

page_text: the gun depressed. The gun a is carried in a cradle or rocking slide band it
recoils in the line of fire.
A bracket is fixed to the cradle with T headed bolts so as to be readily
removable. The sight bar d carrying the sights d' d' is pivotted at d³ near its
fore end to the bracket and about midway of its length it has an arm d projecting
downwards and carrying a pin ds which enters a groove e which is of the required
cam like form. Or the cam groove may be replaced by a cam surface, a spring
being then provided to keep the parts in contact. The cam is mounted upon a
support attached to the gun carriage g it may conveniently be upon the cap g' of
the trunnion bearing, and it is adjustable thereon to compensate any error in the
platform level. The cam is pivotted to the support at f¹ and its fore end is
adjustably connected therewith by a screw h which is used to compensate the rise
and fall of the tide. For the purpose of reading the range a graduated arc i is
provided upon the sight bar.
Another arrangement is shown by Figures 3 and 4 which are side views; the
gun in Figure 3 is horizontal and in Figure 4 it is depressed. An arc of teeth g
is fixed upon the carriage a concentric with the trunnion hearing and on the
cradle b there is a radial axis k with a pinion k¹ engaged with the toothed are;
hence the axis rotates whilst the cradle with the gun is being elevated or depressed.
By bevilled gearing k and the axis & conveys movement to a toothed wheel m
mounted ou the cradle b and the wheel gears with a sliding rack n which it moves
in a fore and aft direction. The rack carries the cani o which is jointed to it at o'
and this cam controls the sight bar as already explained. There are similar
adjustments for height of tide and for error of platform level, the latter adjustment
being made by shifting one of the gear wheels 7 and m around its axis. When the
wheels are correctly set they are clamped together by clamping screws m¹ m².
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. A gun sight substantially as herein described in which a sight bar is at one
point jointed to an attachment upon the cradle and at another point controlled
by a cam surface carried by a support upon the gun carriage.
2. A gun sight substantially as herein described in which a sight bar is
controlled by a cam mounted upon the cradle and connected by toothed gearing
with a toothed arc carried by the gun carriage.
3. In a gun sight in accordance with either of the preceding claims the
adjustment whereby rise and fall of the tide may be compensated.
4. In a gun sight in accordance with either of the preceding claims the
adjustment by which error of platform level may be compensated.
5. A gun sight substantially as represented by the annexed drawings.
Dated this 28th day of September 1896.
A. G. HADCOCK.
R. T. BRANKSTON.