and for Measuring Distances.
Year: 1888

page_text: Date of Application, 12th May, 1888
Complete Specification Left, 12th Feb., 1889
Complete Specification Accepted, 11th May, 1889
and for Measuring Distances.
I, WILLIAM BARTON of 6 Stananought Street Liverpool in the county of Lancashire,
Master Mariner, do hereby declare the nature of this invention to be as follows:-
This instrument is intended to work right angle triangle planes and is for the uso
of ships masters, pilots and others, and consists of a metal or wooden quadrant having
the are of the quadrant divided into degrees and compass points. On the centre of
the quadrant from which the arc is struck is pivoted an arm hereafter called the
pivoting arm moving in the centre, and at each end is a sight vane.
This pivoted
arm is slotted, and on it in this slot works a pin attached to another arm, called here-
after the moveable arm. These two arms and each of the straight sides of the quadrant
are divided into equal parts.
By setting the pivoted arm at certain angles and the moveable arm at certain
distances, when maintained at right angles by the sides of the quadrant, or measuring
off distances on the pivoted arm, and then marking off given distances on the move-
able arm, when also maintained at right angles to the sides of the quadrant, certain
other angles of a triangle and distances are obtained by which a ship may be steered
so as to pass within a given distance of certain objects, or make allowance for currents,
or for setting courses when the deviation of the compass is not known.
HUGHES & COMPANY,
38, Chancery Lane,
Agents for the Applicant.

page_text: .COMPLETE SPECIFICATION.
A New or Improved Instrument for Indicating Angles and Courses
and for Measuring Distances.
I WILLIAM BARTON of 6 Stananought Street, Liverpool in the County of Lancashire
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 instrument is intended to work right angle, triangle planes and is for the use
of ships masters, pilots and others and consists of a metal or wooden quadrant having
the are of the quadrant divided into degrees and compass points. On the centre of
tho quadrant from which the arc is struck is pivoted an arm hereafter called the
pivoting arm moving in the centre, and at each end is a sight vane. This pivoted arm
is slotted, and on it in this slot works a pin attached to another arm, called hereafter
the moveable arm. These two arms and each of the straight sides of the quadrant are
divided into equal parts.
By setting the pivoted arm at certain angles and the moveable arm at certain
distances when maintained at right angles by the sides of the quadrant or measuring
off distances on the pivoted arm and then marking off given distances on the move-
able arm, when also maintained at right angles to the side of the quadrant certain
other Angles of a triangle and distances are obtained by which a ship may be steered
so as to pass within a given distance of certain objects, or make allowance for currents,
or for setting courses when the deviation of the compass is not known.
And in order that my invention may be more fully understood I have shewn the
same in the accompanying drawing in which Fig. 1 is a plan of one form of my
instrument while Fig. 2 is a perspective view of a modified form of the' said
instrument.
My improved instrument shewn in Fig. 1 consists of a metal quadrant q having the
are graduated to degrees and quarter points of the compass as shewn and the straight
sides a a' graduated to any scale of equal parts. The said instrument is moreover
furnished with. two arms b and c graduated to the same scale of equal parts.
The arm bis pivotted centrally and has two sight pins or vanes vv while the arm c
moves in a slots formed in the arm b and can be fixed in any suitable place therein
by means of a screw s.
My improved instrument is used in the following manner :-
1. To find the distance a ship will pass from a light, point of land or the like-

page_text: Take the angle between the course of the ship and the object and set the arm b to
that angle, move the index mark of the moveable arm c to the distance of the object
on the arm b using the scales as miles; bring the moveable arm c parallel to the
scale marks on margin of a.
Read off the scale marks on the moveable. arm from
index mark to inside edge of the margin scale-this is the distance the ship will pass
from the object if the course is made good. And the number of miles between the
centre pivot and the edge of the moveable arm on margin scale, is the distance the
ship will have to run to bring the object abeam.
2. To check the course :-
After running any given number of miles by patent log, note the angle on the
bow of the object, bring the moveable arm c back that number of miles on margin
scale, letting it slide on the pivotted arın b keeping it parallel with the margin scale
marks, and the same distance on moveable arm as at first. Then read off the angle
of the pivotted arm on the instrument. If this angle and the observed angle agree,
the ship is making her course. If the observed angle is smaller than the angle on
the instrument, the ship is being set in toward the object and if larger, away from the
object, and the course may be altered, if necessary. Care must be taken to get the
speed as nearly correct as possible as an error will effect the angle. If the speed is
less than that allowed the observed angle will be less than that on the instrument and
if the speed is greater the angle will be larger.
3. To pass any required distance from an object :-
Set the moveable arm c to the distance of the object on the pivotted arm b and
to the distance required between the index mark and inside edge of the margin
scale, keeping the moveable arm parallel with the margin scale marks. Read off the
angle by the pivotted arm alter the course to bring the object at that angle with the
ship's course.
Steer that course and check it as often as is considered necessary.
4. When the distance of the object is not known―
To pass any distance required from it, judge the distance as nearly as possible and
set the moveable arm to that distance on pivotted arm. Move the arms until the
moveable arm is parallel with marks on the margin scale and is at the distance you
wish to pass from the object. Read off the angle by pivotted arm and alter the
course to bring the object at that angle with the ships course. Note carefully time
and patent log.
Watch the change of bearing carefully, and when it has exactly doubled, note the
time and patent log again. The difference between the two readings of the log will
be the distance of the object at the time of the second observation. Set the moveable
arm to this distance on pivotted arm and find the angle, the object should be on the
bow, as above mentioned. Set the new course by compass, and check it as often as is
considered necessary.
When the first angle on the bow is very small the operation should be repeated, as
the larger the angle the more accurate will be the result.
A modified form of my invention is shewn in Fig. 2 which represents a compass
course and distance indicator inten led for use in combination with a compass, or with
an are as in the instruments above described-or with any other suitable means of
measuring an angle.
The new arms d and e are intended to take the place of the short ones of instru-
ment shewn in Fig. 1, or they may be used independently with a compass or the
like.
The arm d having a central thread t takes the place of the margin scale a of Fig. 1.
and carries a small spirit level at one end (the opposite end to the thread). The
pivotting arm e is provided with sight vanes v. v. at each end and the moveable one o
will be the same as the arın c (fig. 1), the whole instrument should balance as nearly
as possible and be so fitted that it can be easily detached from the arm and secured to
the compass or other instrument.
The instrument is fixed to any suitable beam or frame on the deck of the vessel by
means of the two screws s s².

page_text: 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 improved apparatus for indicating ships courses and measuring the distance
travelled thereby constructed and operating substantially as described and shewn in
Fig. 1 of the drawings and for the purposes set forth.
2. The modification of the improved apparatus claimed above, arranged and coni-
bined substantially as bereinbefore described and shewn in Fig. 2 of the drawings.
HUGHES, SON & Co.,
38, Chancery Lane,
Agents for the Applicant.
HUGHES, SON & Co.,
38, Chancery Lane,
Agents for the Applicant.