An Improved Device to be used in Determining Distances on Land or on Board Ship, and for Facilitating the Working of Problems in Trigonometry.
Year: 1892

page_text: Date of Application, 1st Oct., 1892
Complete Specification Left, 3rd July, 1893-Accepted, 12th Aug., 1893
PROVISIONAL SPECIFICATION.
An Improved Device to be used in Determining Distances on Land
or on Board Ship, and for Facilitating the Working of Problems
in Trigonometry.
JOHN GEORGE LOVERING 149 Romford Road Stratford London Master
Mariner do hereby declare the nature of this invention to be as follows:-
This invention relates to a device to be used in determining the distance of
vessels at sea from any point, such as a light, headland or buoy, and the course
and distance run of the vessel on which it is used, also applicable to the working
of problems in trigonometry, such as are required in surveying and the like.
This device consists of a card, board or metal plate, divided into a number of
squares of equal size by vertical and horizontal lines, drawn, printed or engraved.
A convenient number of squares is 36 for each side, numbered from 1 upwards at
the sides. From one corner of this card proceed a number of lines dividing the
card into the points of the compass, or degrees, the points being subdivided as
required.
The method of using this card on board ship is as follows:-The horizontal lines
are taken to be the course in which the ship is moving at the time, and the corner
to which the radial lines converge, the object sighted. Suppose, for example, that
at the time of the first observation the object is one point on the bow of the ship and
after 15 miles run is at two points.
A distance representing 15 miles, say 15 squares is measured off horizontally
between the lines representing the points, reaching from one line to the other.
Three points are thus represented on the card, corresponding to the first position
of the vessel, the second position, and the object sighted. To obtain the distance
of the object the length of first or second line is taken; to obtain distance at which
the object will be passed, the horizontal line is followed to the end and the vertical
distance noted. If it is desired to pass at a lesser or greater distance, the distance
required is noted on the card and the point to which the ship's head must be
brought obtained.
For use on land a similar method is employed, and if desired, a quadrant
divided into degrees may be placed at the lower corner in order to obtain lines at
any angle across the radial lines, representing the bases of the triangles obtained
by the measurements. Two radial arms may be employed, which can be moved to
any position on the radial lines, the card or metal plate being in this case in the
form of a quadrant to allow of the motion of the arms, which are furnished with
clips which fix them in any desired position. If a reading is taken, one arm is
fixed at the proper angle and at the second reading the second arm is also adjusted.
A small arm or scale suitably divided is preferably employed to measure off the
distance, pivotted to a block sliding in a groove in one arm, in order that it may
be adjusted to any desired point, thus obviating the necessity of using separate
scales or dividers.
Dated this 16th day of January 1893.
GEO. H. RAYNER,
37, Chancery Lane, London, W.C., Agent for the Applicant.

page_text: COMPLETE SPECIFICATION.
An Improved Device to be used in Determining Distances on Land
or on Board Ship, and for Facilitating the Working of Problems
in Trigonometry.
I, JOHN GEORGE LOVERING of 149 Romford Road Stratford London Master
Mariner, 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 :-
This invention relates to a device to be used in determining the distance of
vessels at sea, from any point, such as a light, head-land or buoy, and the course
of distance run of the vessel on which it is used, the device being also applicable
to the working of problems in trigonometry, such as required in surveying and the
like. The device consists of a cardboard, metal or other plate, divided into a
number of squares of equal size by vertical and horizontal lines, drawn, printed, or
engraved. A convenient number of squares is thirty six for each side, numbered
from one upwards along the sides. From one corner proceed a number of radial
lines dividing the card into degrees points of the compass or other angle units from
the said point, and in some cases a second quadrant is furnished, struck from an
adjacent corner in order that lines cutting the squares and the above mentioned
radial lines may be drawn at any desired angle. To facilitate the use of this
device, two arms may be employed pivotted at the corner from which the radial
lines proceed, which can be opened to any required degree, another adjustable arm
crossing them for the purpose hereinafter described.
In order that the invention may be more clearly understood reference is had to
the accompanying sheet of drawings in which
19
Fig. is a plan of the card showing the divisions in detail,
Figs: 2 and 3 are respectively a plan and side elevation to a smaller scale of an.
arrangement in which pivotted arms are used as above mentioned and
Fig. 4 is a detail view, showing a section of two of the arms.
The card or plate A is divided into equal parts by the horizontal lines B and the
vertical lines C forming a number of squares, thirty six spaces to each side being
shown in Fig. 1, each of which represents in using the card a definite length; a
inile for example when employed on the sea, or for long distances. From the
corner or point a of the card proceed the radial lines D d, the lines D dividing the
card into points of the compass and d into smaller parts. A quadrant E is also
furnished, being formed by the edge of the plate in Fig. 2, divided into degrees, to
allow of other measurements, and a second quadrant Fat the adjacent corner.also
provided with a scale.
The method of using this card on board ship is as follows:-
The lines B are taken to be the course in which the ship is moving at the time,
and the point a the object sighted. Suppose for example that at the time of the
first observation the object is one point on the bow of the ship and after fifteen miles
run is at two points.
A distance representing fifteen miles is taken, say fifteen of the vertical lines or
squares, and measured off horizontally between the radial lines D, representing the
first and second point. Three points are thus represented on the card, corresponding
to the first position of the vessel, its second position and the object sighted.
To obtain the distance of the object at either observation one of the two radial
lines is measured off from the point a to the position of the ship. The horizontal
line on being followed to the end will give the point at which the ship will pass the
object sighted and the distance can be at once obtained.
If it is desired to pass it at a greater or less distance, the distance required is
noted on the card and the point to which the ships head must be brought obtained.
For surveying purposes the quadrant F is employed to obtain a line at any

page_text: required angle across the radial lines D d instead of always using the horizontal
lines.
Referring to Figs. 2, 3 & 4 two arms G. H are pivotted at a to the plate A
which in this case is preferably made of metal, and of quadrant form instead of
square as in the arrangement above described. These arms are furnished with
scales, divided to any required degree of fineness and are arranged so that their
inner edges will proceed radially from the point a. The arms can be turned to any
angles and are furnished with clamps g, h at their ends to secure them in any
position on the plate.
The arm G is formed with a slot g¹ extending longitudinally for the greater part
of its length. A third arm J is employed extending across the other two, generally
horizontally, having a pin sliding in the said slot g' and allowing the arm J to
move up and down G without becoming detached, a nut or other device being used
to fix it in any required position. The arm J is also furnished with a scale, and a
small slot j' is formed in it so that when adjusted the zero point of the scale will be
directly over the edge of the arm G. The detail view Fig. 4 shows one arrange-
ment of the arms G and J, the slot g¹ having rebated edges to retain the head of
the pin. The arm J can thus be moved about to any point on the arms G & H
measuring the distance between them accurately, the observations being conducted
in the same manner as that above described.
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) A device or instrument for determining distances of objects and like
problems consisting of a card or plate, divided into squares of equal dimensions by
a number of lines, and having lines radiating from a point at one corner, crossing
the squares and dividing the card regularly, the lines being numbered in a suitable
manner substantially and for the purposes specified.
(2) In a device of the kind described a plate divided as described in the fore-
going claim, having two radial arms pivotted at one corner and a cross arm capable
of moving up and down on the said radial arms and measuring the distance between
them on a given line, substantially as described and for the purposes specified.
(3) In a device of the kind described, a plate divided as described in the first
claim furnished with two pivotted radial arms one having a slot, in which a pin
engages carrying a third measuring arm which traverses the radial arms being
fixed in any desired position, substantially as described and for the purposes
specified.
(4) The improved device for determining the distances of objects and like
problems, consisting of a plate divided in the manner described, two radial pivotted
arms with clamps at their ends, and a cross arm sliding on the others in a groove,
and capable of being fixed in any desired position substantially as described and
shown in Figs. 2, 3 & 4 and for the purposes specified.
(5) The improved device for determining the distances of objects and like
problems constructed and applied substantially in the manner described with
reference to the accompanying drawings.
Deted this 3rd day of July 1802
GEO. H. RAYNER,
37, Chancery Lane, London, W.C., Agent for the Applicant.