Improvements in Range Finders, and in Means for Effecting the Elevation of Artillery to be used in Combination with Range Finders.
Year: 1892

page_text: Date of Application, 18th Jan., 1892
Complete Specification Left, 18th Nov., 1892-Accepted, 14th Jan., 1893
PROVISIONAL SPECIFICATION.
Improvements in Range Finders, and in Means for Effecting the
Elevation of Artillery to be used in Combination with Range
Finders.
I, ROWLAND BROTHERHOOD, of No. 28, Victoria Street, S.W., in the County
of London, Engineer, do hereby declare the nature of this invention to be as
follows:-
'
+
My; invention relates to improvements in range finders and in means for effecting the
elevation of artillery to be used in combination with range finders. The range finder
consists of a suitable stand and telescope. In addition to these there are provided a
pair of bars. One of these bars is graduated. This latter is fast on the top of the
stand. The telescope and the other bar are fast together and are pivotted upon
the stand, their axes being mathematically co-incident with zero on the scale. A
sliding wedge is provided for the purpose of moving the telescope on its pivot as it
(the wedge) is moved towards the centre of the instrument-the axis above
mentioned. For the purpose of moving, the wedge in either direction lengthwise,
a suitable hand wheel and endless.screw gear is provided. The wedge is also set
out as 'a vernier. For the purpose of enabling the instrument to take an angle on
either the right or the left hand, I provide a suitable screw or toothed, gear, the
axis of which is co-incident with.zero on the vernier, and by means of which the
bar and telescope are turned to the right or the left on their common pivot as may
be required. The instrument is used as follows:-A sight is taken for the purpose
of establishing.a.right line. A base of any length is then set off at 90° therewith,
starting from the projection on the ground of the centre of the instrument, and
each unit on the scale is the geometrical equivalent of the length of this.base.
The instrument is then transferred to the other end of the base and the wedge drawn in
until the object is sighted, or the right angle involved may be taken by any other
means. The plain bar will then be a portion of the hypotheneuse, and where it
cuts the scale. as indicated by the vernier is the range, the base x by the scale-
reading. The relative positions of the pivotted and fixed portions of the instrument
may be reversed. When the range. finder is used with artillery there is combined
with the platform of the gun a circular inclined plane having its maximum in front
and two minima right and left. Each incline. is scaled for elevation according to
the trajectory of the gun. Both scales, therefore, terminate in the maximum.
The platform (which, may be a special one) is slewed so as to bring the base
line 90° with the sight line,, and the proper elevation, effected by the respective
incline.
Dated this 18th day of January11892.
-
PHILLIPS & LEIGH,
Agents for the Applicant.
'
COMPLETE SPECIFICATION.
'Improvements in Range Finders, and in 'Means for Effecting the
Elevation of Artillery to be used in Combination with Range
"Finders.
I, ROWLAND, BROTHERHOOD, formerly of No. 28, 'Victoria Street, S.W., but
now of. No. 5, The Sanctuary, Westminster, both in the Administrative County of
London, Engineer, 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 :—
Mysinvention relates to improvements in rangefinders and in means for effecting

page_text: the elevation of artillery. These means are intended to be used in combination
with the particular type of range finder hereafter specified with reference to the
accompanying drawings, but such use is not necessarily limited to the said com-
bination. Neither is the invention restricted to being used in combination with
artillery but may be used for the purpose of finding both range and elevation for
small arins.
In order that the invention and the means by which it is to be carried into
practical effect may be thoroughly understood, I will now describe it and them in
detail, referring in so doing to the accompanying drawings which are to be taken
as part of this Specification and read therewith.
Fig. 1 is a sectional rear elevation shewing the range finder combined with 'a
sighting telescope upon a carriage,
Figs. 2 and 3 are clevations from the left and right sides, respectively, of
Fig. 1.
Fig. 4 is a plan illustrating the use of the range finder.
Fig. 5 is a sectional elevation of the improved range finder.
Fig. 6 is a plan omitting the telescope but including part of the carriage
illustrated in Figs. 1 to 4.
Fig. 7 is a side elevation illustrating the connection between the vernier block
and its traversing screw.
Fig. 8 is a transverse sectional elevation of the fixed bar, the vernier block, the
pivotted or telescope bar, the traversing gear and the connection between the
vernier block and the telescope har. It is taken on line 8-8 of Figs. 5 and 6.
Fig. 9 is a sectional side elevation illustrating the range finder constructed for
use under circumstances where it is impossible to set out a base line horizontally.
Fig. 10 is a sectional side elevation of my improved elevation finder.
Fig. 11 is a plan corresponding therewith and illustrating its use.
Fig. 12 is a side elevation of the improved elevation finder shewing it applied to
a piece of ordnance.
Referring to Figs. 1 to 8, a is a straight tube and b is a second one of smaller
diameter supported inside it, the two tubes having a common axis. The object of
the tube b is to carry the range finder and a sighting telescope hereafter described
at its ends, respectively, and that of the tube a to prevent the other being damaged.
It is a matter of convenience to which end of the inner tube either instrument is
attached. are bushes in the ends of the tube a.and in them the tube b is
supported and can be turned about its axis. It fits its bushes with sufficient tightness
to keep it in any desired position. 62 is a handle fast to the tube b. It is provided
for the purpose of turning the latter about its axis so as to bring the two telescopes
described further on into the plane common to the object and to the eye of the user
of the instrument. c is a wheeled carriage upon which the tube a is rigidly mounted,
and c', c' are legs pivotted to the latter, by means of which it can be held steadily
during the time that the range finder is being used. Both carriage and legs may
be of any convenient construction. The object in providing a carriage, as dis-
tinguished from a stand, to make the whole combination illustrated in Figs. 1
to 4 easily portable.
Although the tubes a and b are shewn as supported in the horizontal plane, it is
to be distinctly understood that the invention can be used with the base line which
they represent, in any position, horizontal inclined or vertical, as circumstances may
require.
13
d is the sighting telescope fast upon one end of the tube 6 at a right angle
with it. Ordinary sights may be substituted if the distance is not long enough
to render the use of a telescope indispensable, and are to be understood as
included, for the purpose of this invention, within the term "sighting telescope."
The range finder is made fast by the head of its fixed bar to the other end of the
tube at right angles therewith, parallel with the sighting line and in the same
plane as it.
The fixed bar of the range finder consists of a flat bar e, a pair of parallel flat

page_text: bars, a head e, T-shaped in cross section, and a strengthening web e². The
bars are set edge up. These, as well as the flat bar e, the head e and the web e
are, preferably, made in one piece.
The outer faces of the bars are both graduated to the same scale. The zeroes
of these scales f¹ are aligned with the axis of the tubes a and b and each scale is
at the same distance, right or left, from the centre line of the range finder.
g is a telescope fast upon and aligned with a bar h. is a round socket upon the
head of the range finder. ¡ is a round block made fast to the telescope and
telescope har, with its axis making a right angle with that of the telescope. It
fits in the socket with sufficient tightness for the telescope and the telescope bar to
move steadily about its axis. This axis is the centre of the instrument. j is a
groove in the periphery of the round block into which the noses of set screws j
working through the socket enter for the sake of keeping the block in the socket.
My invention requires a device by which the telescope bar and the telescope
with it, can be slewed to either hand upon their common axis with reference to
the fixed bars for either of them. This slewing, with the consequent reading upon
the scales for either of them, is the motion which constitutes the action of the
range finder. The device in question is described in the Provisional Specification
as a sliding wedge, inasmuch as its being moved towards the centre of the instrument
slews the telescope bar from the fixed bar, the distance between any two formerly
contiguous points on them, respectively, or, in other words, the angle through
which the telescope bar is slewed-increasing pari passu with the motion of the
device towards the centre of the instrument. The device illustrated is as follows.
is a block fitting the channel between the two bars, and capable of motion
therein either backwards or forwards. It is provided with two verniers A¹
each adapted to read in connection with the respective scale is a screw
supported in suitable bearings. The bearing for its front end is in the closed
front end of the channel, and the rear bearing is in the socket i and a stationary
filling piece, through which the shank of the screw is continued to the rear far
enough to carry a band wheel which is provided for the purpose of turning the
screw about its axis in either direction. This motion about its axis is the only one
of which it is capable. The engagement of the screw with the block k also
provides for the latter being kept in its working position. This engagement with
the vernier block is effected by passing the screw through a correspondingly
threaded hole in it, so that a rotary motion on the part of the hand wheel
becomes a linear one in the block in direction according to that of the motion
of the hand wheel. is a central longitudinal groove in the under face of the
telescope har h. is a vertical stud having its base upon the top of the block k
and engaging the telescope bar by entering the said groove. It is carried by a
horizontal transverse screw which has its bearings in the block k in two lugs.
The axis of the screw and the zero of the vernier are aligned with each other.
The screw terminates at cach end in square so that it can be turned about its
axis by a suitable key. By engaging with the stud 2 it is adapted to move the
latter to either side in the same way as the screw moves the block to or fro.
The screw further serves to hold the stud to the vernier block in the sense
that they shall both be moved together by the screw and, as a further
consequence, the block must operate as the agent for effecting the necessary
slewing. A vertical mark is made centrally upon one face of the base of the
stud, and one also centrally upon the corresponding face of the vernier
block k and therefore coincident with the centre line of the instrument.
marks coincide when the telescope bar and the fixed bar are aligned. The said
centre line is not actually marked in the instrument illustrated. It runs from the
centre forwards through the mark k.
These
Scales k², kº, are set out right and left of the mark which consequently serves
as a zero point for them both, and the scales are set out to correspond with the
scales k, k³.
With reference to the position of the scales f, I have to point out that the

page_text: invention requires the presence of a scale upon which can be read off the distance
of the axis of the stud 2 from the centre of the instrument. This scale might be
upon the plate e along the centre line, but, for the sake of legibility, I place it
upon the outer faces of the bars. The faces of the vernier block,are graduated
to read with the respective scale f.
I wish it to be distinctly understood that my invention does. not confine me in
respect of the details of the mechanism which I make use of for, effecting the
slewing of the telescope and its bar. with, reference to the fixed, bar, by means of
a to and fro travelling block with which is combined a vernier, reading with, the
scale or scales on the said fixed bar; and, provided; that the, discharge of; the
relative functions herein set out is provided for, the details may be modified, within
the limits prescribed by my Provisional Specification.
As far as my invention and its use are concerned, the, range finder, may, be
mounted upon its own stand, the sighting telescope or its equivalent, the tubes a
and band the carriage being dispensed with, but it is preferable, that the sighting
telescope and the tubes be used, they being mounted with the range, finder upon
the same stand; and that stand a carriage, for the following reasons. The measured
base line (described at length further on) is ready to hand and the whole
combination is rendered easily portable.
In finding a range with my improved range finder there,are,,set out two right
angle triangles. One is. larger than the other, the smaller being in fact, a
reproduction of the larger one on a much, reduced scale. Both have one angle
in, common viz., the one opposite to the perpendicular. Further this angle
coincides with the centre of the range finder.
The following is the way in which the range finder, is used.
(a). When the range finder is used alone. A sight is, taken through, the
telescope at the object the range of which is to be ascertained. This produces
an imaginary line, which is. for the purpose of this Specification hereinafter
referred to as the sighting line a base line is measured off, to the right, or the
left, whichever the circumstances of the case may require, from the projection
on the ground of the eye piece of the telescope or of its equivalent, at a right
angle with, the sighting line. The instrument is then moved to the other end of
the base line and set with the respective scale fat a right angle therewith and
its zero immediately over the, said end.
•
It must be understood that the sighting line and the base line may, both be
obtained by means of any suitable instrument, without it being necessary to have
recourse to the telescope of the range finder..
(6). When the combination of range finder, sighting telescope, tubes and carriage
is used, the base liner is measured off at the proper angle with the sighting
telescope, and the range finder put into position by the act of sighting, the object.
This base line is the distance separating the axis of one, telescope from, the axis, of
the other.
It is to be understood that both telescopes are under, either condition (a) or, (b)
in the plane common to the object and the eye of the user, of the instrument.
The further use is the same under conditions (a) or (b) and is as follows..
The studs is traversed by means of the traversing screw towards the same
side of the instrument as the object to be sighted is.on. In Figs. 4.and-6. the
object is supposed to be on the right hand. The stud may be. traversed past one
or more divisions of the scale on the face of the vernier, as. may be convenient-
say; two.
The scale must be read accordingly, i.e., as if. two of its divisions
were one, because the distance which the stud is traversed is. in any case, the unit
of the instrument for the range to be found, while the linear value of it is. that
of the measured base line.
The traverse of the stud above mentioned swings the telescope, on its axis
accordingly, and provides for, its being subsequently slewed into the line of sight
by the motion of the vernier block towards the centre of the range finder: The
hand wheel is turned until this motion has slewed the telescope, far enough for

page_text: the object to be sighted through it. The line of sight between, the observer and
the object is the hypotheneuse subtending the right angle which, is made by the
base line with the sighting line. The reading on the scale f1 which the zero line
of the vernier cuts is the range and is reduced to feet, or whatever is, the linear.
unit of, the measured base line, by multiplying it, by the number. of such-linear.
units in the said base line..
Thus, assuming, that the length of. the base line is. 10 feet, that, the stud.k²-was
moved over 2 divisions on the scale 8 and that the reading on the scale, is 300
then the range of; the object from the sighting telescope is
300.x 10-
2
Under these circumstances the following correspondences are present:
}
the },
The centre line of the instru-
ment represented by the scale f¹
The distance through, which the
studis traversed,
The hypotheneuse from the centre.
off the range finder to the inter-
section of the scale by the vernier
The distance on the scale f' from
its zero to the bisected reading.
with
"
"
23.
{
or, 1500, feet:
The line from d to and, through.
the object.
The measured base, line, being the
base of. the larger, triangle.,
The hypotheneuse subtending, the
angle: which the base line and; the
sighting line make with each other;
being, the hypotheneuse of the larger
triangle.
Range of object from d, being
the perpendiculare of the larger
triangle.
Referring to Fig. 9, m. represents what would be the captain's bridge of; a
man.o.war, or the station taken by the officer whose duty is to use, the range,finder,
and m is the stand, of. the instrument. The tubes, a and are necessarily
supported in gimbals or their equivalent in the head of, the stand, from which they
hang, downwards through the bridge or its equivalent to within a suitable distance
of the fighting. deck or its equivalent. The range finder. consequently works,iu
the vertical,plane. n is a hand,wheel fast-to the inner tube .. It is provided.as
a means for, turning both telescopes to the same point of the compass at a time..
The principle and details. of construction and. consequently, the use, of, the
modification of the invention last described are the same as those already, set forth.
With reference to that part of my invention which provides for the rifleman or
the gunner.getting the correct elevation by the act of sighting his, object, I.make
use of an inclined or stepped plane, arc shaped or rectilinear in plan, on each side
of, the arm.
The two planes meet each other near the front of the carriage of, the arm, the
line of meeting being in, the vertical plane which passes through the axis of the
barrel. Each incline is sloped for elevation, according to the trajectory of.ther arm,
and scaled for range.
The barrel is provided on its under.side with. a suitable
extension or contact block or plate which is adapted to rest upon or move-over
either incline. So that, the distance being given, the act of slewing the arm until
the block, or plate is over, that distance on the scale, elevates. the barrel
accordingly.
The relative positions, of the block or plate and the inclines may be reversed to
the extent of setting out, both the incline and the scale upon a plate depending
from the underside of the barrel and making the top surfaces of the circular, or are
shaped pieces horizontal. This reversed position is the one illustrated in Figs. 10,
11 and 12.
Suitable provision is. made in the construction of the platform. for the arm; to.be
slewed so as to bring the base line to a right angle with the sighting. line.
Referring to Figs. 10 and 11, the invention is shewn therein as constructed for
the use of infantry. A,suitable carriage is provided, but this..is .omitted, from the
figures because it does not form, any part of, the present invention..

page_text: o is any convenient vertical post which is made fast upon the carriage, and o' is
a cap adapted to turn upon and about the post. 02 is a hand lever provided for
the purpose of slewing the platform round until the radius between the bars p*, p
described further on makes a right angle with the measured base line. 03, 0³ are a
pair of sights to be used in getting that angle. is the base plate. It is pivotted
for motion in the vertical plane at upon the top of the cap. p is the platform
adapted to turn upon the base plate p. They are held together by rings p³ which are
made fast to the base p. The basep, the platform p² and the ring p³ are concentric,
and their common centre is that about which the arm is turned. p, p are a pair of
arc shaped bars. It is of no moment whether they are are shaped or rectilinear in
plan provided that their surfaces are within the sweep of the contact plate. They are
made fast, to and project out from the ring with their top surfaces parallel with the
axis of the arm when the latter is at point blank. Further, they are duplicates of
each other, stand symmetrically right and left of the prolongation of a radius of
the ring and nearly meet in the said prolongation. p p are a pair of cheeks
standing up from the platform p², and p, p are the respective trunnions. pis
the contact plate. It is made fast to the underside of the barrel of the arm and
stands in the vertical plane bisecting the axis of it. The front portion of the
bottom edge of this plate is parallel with the said axis. y is a notch between the
converging ends of the bars p¹, in which this front portion of the plate rests for
the point blank position i.e., that where the range is so short that no clevation is
needed..
ast.
The remaining portion of the bottom edge of the contact plate p' is cut
according to a parabolic curve which is calculated from the elevation required
for a range of the same length as the hypotheneuse of a right angle triangle of
which the base and the perpendicular are known. Both bars are marked with
the same scale pe which serves to indicate the ranges for the respective elevations.
This being the relationship between the curve of the contact plate and the
scale it follows that the motion of either the respective are under the contact
plate, or of the latter over the former, until that division on the scale which
represents the known range of the object to be hit, coincides with the plate, imparts
the correct elevation to the barrel for that range. It is to be noted that in
calculating the curve and scale, either or both, the trajectory of the particular arm
to which the invention is to be applied must be allowed for.
The dotted lines of Fig. 10 represent the arm at the proper elevation for a range
of 1000 yards along the hypotheneuse. The dotted lines 1 and the full lines as well
as the dotted lines 2 of Fig. 11 represent it in the positions it would occupy when
elevated for ranges of 800 and 100 yards, respectively.
The direction of the scales on the face of the bars p* as well as that of the curve
may be reversed.
gis a resilient spring between a bracket g² on the front side of the cap o' and
the base p. g is a screw working through a bracket gt on the rear side of the
cap and having its nose always in contact with the base p. The spring and screw
constitute a device by which the arm can be laid in the plane of the object to be
hit. The relative positions of the said spring and screw may be reversed.
The invention constructed as above described is used as follows. The cap o' is
slewed round until the radius which bisects the notch y is at a right angle with the
base line. If the arm is then turned on its pivot until the object is sighted through
the telescope go, it is at the proper elevation for hitting, and the range can be
called out from the scale on the bar p¹ which range is the length from the other
end of the base to the object.
Referring to Fig. 12, it will be seen that I have selected a Nordenfeldt gun for
illustrating the application of this part of my invention to artillery. r is the hand
wheel of the gear for slewing the gun upon its base for the purpose of bringing
the axis of the gun to a right angle with the base line; and s, that of the gear for
laying the gun in the plane of the object. The bars pt and their ring are slewed
independently of the gun by any suitable mechanism.
..

page_text: The elevation finder is of the same construction and operation as described with
reference to Figs. 10 and 11. The scale p on the contact plate is projected from
the scale 8 on the arc shaped pieces p..
The combination of the range finder illustrated in Figs. 5 to 8 and the elevation
finder illustrated in Figs. 10, 11 and 12 is effected as follows.
The telescope of Fig. 5 is replaced by the arm, the axis of the bore of the
latter and the centre line of the range finder standing in the same vertical plane.
The contact plate p' discharges the function of the fixed bar and the slewing
mechanism is underneath. The scale f¹ is replaced by the scale p. The indica-
ting vernier is dispensed with. With this combination it becomes unnecessary to
calculate the length of the range because the knowledge of it has been applied
automatically by the mechanism.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
:-
1. The combination of a graduated fixed bar, a bar pivotted thereupon at its
zero, a compound device engaging with both the said bars and adapted by a trans-
verse motion of one part of it upon the other to move the pivotted bar away from
the fixed one and capable of motion along the fixed bar so as to increase the angle
which the two bars make with each other, as set forth.
2. The combination of a graduated fixed bar, a bar having a telescope or
equivalent sighting device aligned with it and fast to it, a pivotal connection
between the two bars in virtue of which the pivotted bar can be moved to either
hand over the fixed bar, and a device adapted to slew the pivotted bar away from
the fixed bar and to be moved upon the latter towards the said pivotal connection,
a scale upon the device and a scale upon the fixed bar, the two scales being to the
same unit but at right angles to each other, as set forth.
3. The combination of a fixed bar, pivotted bar, telescope, groove in the pivotted
bar, stud, traversing screw, vernier block, scale thereon, and scale on the fixed bar,
all co-operating together as and for the purpose set forth.
4. The combination of a contact plate depending from the barrel of the arm in
the vertical plane which passes through the axis of the barrel and having its
bottom edge cut according to a certain parabolic curve, with bars standing right
and left of a prolongation of a radius of the platform of the arm and a scale of
ranges upon each of the said bars, as set forth.
5. The combination of contact block upon the under side of the barrel of the
arm and a fixed incline right and left of a prolongation of a radius of the platform,
of the arm, the top face of each incline being set out according to a certain
parabolic curve and marked with a scale of ranges, as set forth.
6. The combination with the barrel of an arm, of contact block or contact plate,
a bar fixed to, the platform on each side of a prolongation of a radius of the
latter and in the path of said block or said plate, a certain parabolic curve consti-
tuting the bottom edge of the said contact plate or the top face of each of the said
fixed bars, an adjustable device engaging with both the barrel and the platform,
capable of motion in the direction of the axis of the bore of the barrel and at right
angles with it, mechanism for moving the said device to either hand at a right
angle with the said axis and subsequently in a line therewith, a scale for the trans-
verse motion of the said device and a scale of ranges on each of the said fixed bars,
as set forth.
Dated this 18th day of November 1892.
PHILLIPS & LEIGH,
22, Southampton Buildings, Chancery Lane, W.C.,
Agents for the Applicant.