IMPROVEMENTS IN SEXTANTS OR QUADRANTS FOR NAUTICAL PURPOSES, AND WHICH ARE ALSO ADAPTED TO THE MEASURING OF ALTITUDES OR ANGULAR DISTANCES
Year: 1859

page_text: LETTERS PATENT to Alexander Morton, of Morton Place, Kilmarnock,
for the Invention of "IMPROVEMENTS IN SEXTANTS OR QUADRANTS FOR
NAUTICAL PURPOSES, AND WHICH ARE ALSO ADAPTED TO THE MEASURING OF
ALTITUDES OR ANGULAR DISTANCES."
Sealed the 29th September 1859, and dated the $1st March 1859.
PROVISIONAL SPECIFICATION left by the said Alexander Morton at the
Office of the Commissioners of Patents, with his Petition, on the 31st
March 1859.
I, ALEXANDER MORTON, of Morton Place, Kilmarnock, do hereby declaro
the nature of the said Invention for "IMPROVEMENTS IN SEXTANTS OR QUADRANTS
FOR NAUTICAL PURPOSES, AND WHICH ARE ALSO ADAPTED TO THE MEASURING OF
ALTITUDES OR ANGULAR DISTANCES," to be as follows:-
The improvements have for their object simplicity of construction and
adaptation of parts of instruments for the purpose of measuring altitudes or
angular distances. And according to my improvements the measuring of
angular distances between any two objects may be obtained by the use of a
single reflector. The rays are only once reflected, though several reflectors
may at the same time be employed. For this purpose a reflector is placed
before a telescope, the incident or direct rays of which are divided into two or
more parts, this reflector is to receive the incident or direct rays from objects
at an angle to the axis of the telescope, and to bend or reflect them into the
telescope, while at the same time objects may be seen by the direct rays of the
telescope, or to bend and reflect them to the eye of the observer without a

page_text: telescope, and objects may be seen in a straight line from the eye of the
observer. The inclination of the reflector to the axis of the telescope is the
angular distance between the objects. When more than one reflector is used,
the one is placed as above stated, the others are placed farther from the
telescope, to receive and bend the rays from objects not in a direct line
with the axis of the telescope, so that both or more reflectors receive incident
rays, and bend them into the telescopo froin objects at different angles to the
axis of the telescope. The difference of the inclination of the reflectors will
be the angular measurement between the objects.
Also the improvements relate to adapting colored glasses to such character
of telescope, and placing them between the reflectors and the object glass.
In carrying out my improvements when the angular distance between two
objects only is sought to be obtained, I place a reflector in front of the object
glass of the telescope, and at an angle to the axis of it, in such manner that
whilst the rays from one object to be viewed may be deflected by such
reflector through the telescope, another object at the same time may be seen
by direct rays. When several objects at different angles are to be seen at the
same time, I employ several reflectors. The most convenient form I have
found for these reflectors is to make them circular, or of such shape as to
intercept the central portion of the rays passing through the telescope, leaving
an annular ring of direct rays from the object seen directly. And when
employing several reflectors at tlie same time, I prefer to form one to take the
central rays, and tho others annular rings round the same. The colored
glasses are formed to correspond, one set with the central rays, and others
respectively with the concentric or annular rings. I also use a spirit level on
telescope, and a compound limb for reading off the angle.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alexander Morton in the Great Seal Patent Office on the
80th September 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MORTON, of Morton Place, Kilmarnock, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirty-first day of March, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Alexander Morton, Her special licence that I, the said Alexander

page_text: Morton, my executors, administrators, and assigns, or such others as I, the
said Alexander Morton, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "IMPROVE
MENTS IN SEXTANTS OR QUADRANTS FOR NAUTICAL PURPOSES, AND WHICH ARE ALSO
ADAPTED TO THE MEASURING OF ALTITUDES OR ANGULAR DISTANCES," upon the
condition (amongst others) that I, the said Alexander Morton, my executors
or administrators, by an instrument in writing under my, or their, or one of
their hands and seals, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Alexander Morton, do hereby declare
the nature of the said Invention, and in what manner the same is to be per:
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
The improvements have for their object simplicity of construction and
adaptation of parts of instruments for the purpose of measuring altitudes or
angular distances. And according to my improvements the measuring, of
angular distances between any two objects may be obtained by the use of a
single reflector. The rays are only once reflected, though several reflectors
may at the same time be employed. For this purpose a reflector is placed
before a telescope, the incident or direct rays of which are divided into two or
more parts; this reflector is to receive the incident or direct rays from objects
at an angle to the axis of the telescope, and to bend or reflect them into the
telescope, while at the same time objects may be seen by the direct rays of the
telescope, or to bend and reflect them to the eye of the observer without a
telescope, and objects may be seen in a straight line from the eye of the
observer. The inclination of the reflector to the axis of the telescope is the
angular distance between the objects. When more than one reflector
is used, the one is placed as above stated, the others are placed farther from
the telescope, to receive and bend the rays from objects not in a direct line
with the axis of the telescope, so that both or more reflectors receive incident
rays, and bend them into the telescope from objects at different angles to the
axis of the telescope. The difference of the inclination of the reflectors will
be the angular measurement between the objects.

page_text: Also the improvements relate to adapting colored glasses to such character
of telescope, and placing them between the reflectors and the object glass.
In carrying out my improvements when the angular distance between two
objects only is sought to be obtained, I place a reflector in front of the object
glass of the telescope, and at an anglo to the axis of it, in such manner that
whilst the rays from one object to be viewed may be deflected by such reflector
through the telescope, another object at the same time may be seen by direct
rays. When several objects at different angles are to be seen at the same
time, I employ several reflectors. One form for these reflectors is to make
them circular, or of such shapo as to intercept the central portion of the rays
passing through the telescope, leaving an annular ring of direct rays from the
object seen directly. And when employing several reflectors at the same time,
I prefer to form one to take the central rays, and the others annular rings
round the same; the colored glasses are formed to correspond, one set with the
central rays, and others respectively with the concentric or annular rings. I
also use a spirit level on telescope, and a compound limb for reading off
the-angle.
I will now describe my instrument under the divisions or variations, or
adaptations.
Firstly, when two reflectors are used and a telescope. Secondly, when two
reflectors are used without a telescope. Thirdly, when only one reflector
is used.
:
:
The object of single reflection is this, when the rays from any object are
reflected from a plane surface, tho angle of incidence is equal to the angle of
reflection, and consequently the arc measured by degrees will be shewn on the
limb of the reflector in half degrees. Where the rays are twice reflected, as
in sextants and quadrants at present in use, the limb of the reflector where
the observation is made will indicate quarter degrees for cach degree of the
arc measured. By single reflection then, the scale is twice as large as by
louble reflection. c (in the instrument shown by Figures 1, 2, and 3,) is an
arc of metal or any suitable substance, it will be divided into degrees, &c.,
in the usual manner; d, moveable limb turning on the centre d' of the
arc. a is a telescope fastened on an arc, the axis of which passes through
the centre of arc; on the moveable limb is fastened a reflector b,
which receives the rays from the object to be measured, and they are reflected
into the telescope; parallel with reflector 6 is placed a reflector b', fastened to
the frame of the instrument. When the limb d indicates zero, or 0 of the
scale, the surfaces of the two reflectors b, b' are in the same plane, so that
when they are in this position any object observed will coincide in all its parts

page_text: in the same way as if it was only one reflector, and this is the proof to test
whether the instrument is in proper order, for when in this position the limb
will indicate zero of the scale. The reflectors used in this case are each in
breadth half the diameter of object glass of telescope, and of length suitable
to receive all the rays of light when placed about an angle of 20° from axis of
telescope. The colored glasses f, which turn upon an axis f¹, are made to
correspond to each reflector, and are moveable, and placed between the object
glass of telescope and reflectors, or they can be placed in the eye-piece of
telescope. The spirit level 9 is placed beside the reflectors, and in that
position when it indicates level, the observer would see the horizon at sea in
the middle of the telescope, and consequently if the spirit level indicates level;
although the horizon is not visible, the sun being brought down to the hairs
of telescope, and thus measure its altitude without seeing the horizon. This
instrument is used in the following manner :-It is held in such a position
that the rays from the horizon or any object are received on the fixed reflector b¹;.
and reflected into the telescope, and the rays from other object to be measured
are received on moveable reflector 6 which is now moved till they are
observed to be in the same line, and the angle formed by the two reflectors
which is read off on the arc is the angle between the two objects. And in
order that this may be read off more easily, there is a limb d' placed on
limb d, having its centre near the scale, and its longer end will shew on a
larger scale, and consequently more minute.
The instrument shewn by Figure 4 is in every respect the same as that
shown by Figures 1, 2, and 3, excepting that I use no telescope, only a small
plate with eye-hole or holes in it. This plate is placed in the same position
as the eye-hole of the telescope, and it is fastened on the arc, and the sun
glasses are placed between the plate and reflectors in the same way, each set
for each reflector; this instrument will shew the objects inverted.
The instruments shown by Figure 5 is also in every respect the same as
that shewn by Figures 1, 2, and 3, excepting the reflectors. There is only
one placed on the centre of the arc, and the axis of telescope falls directly
or passes through its centre, and it may be made circular or any other shape,
but I will say, circular, and its diameter is about one-half of diameter of object
glass of telescope. The observer looks straight forward with the outside rays
of telescope for the one object, and the other is reflected into the telescope, and
the angle formed by the inclination of the reflector and axis of telescope is the
angular distance between the objects. It may be used in the same way as the
instrument represonted by Figure 4 without a telescope, the angle formed by

page_text: the line passing through its centre and eye-hole, and the inclination of the
reflector to said line is the angular distance between the objects.
Having thus described the nature of my said Invention, and the means
which I adopt in carrying the same into effect, I would have it understood
that I do not confine myself to the precise details referred to, so long as the
peculiar character of the improvements be retained, substantially as explained.
In witness whercof, I, the said Alexander Morton, have hereunto set
my hand and seal, this Twenty-eighth day of September, in the year of
our Lord One thousand eight hundred and fifty-nine.
Witness,
ANDREW KERR,
Glasgow.
ALEXANDER MORTON. (L.S.)