IMPROVEMENTS IN MARINERS' COMPASSES AND THE PARTS IN CONNECTION THEREWITH, AND IN THE APPLICATION THEREOF TO MAGNETIC INSTRUMENTS
Year: 1863

page_text: LETTERS PATENT to Robert Alexander, of Islington, Liverpool, in the
County of Lancaster, for the Invention of "IMPROVEMENTS IN MARINERS'
COMPASSES AND THE PARTS IN CONNECTION THEREWITH, AND IN THE APPLICATION
THEREOF TO MAGNETIC INSTRUMENTS."
Sealed the 11th September 1863, and dated the 14th March 1863.
PROVISIONAL SPECIFICATION left by the said Robert Alexander at
the Office of the Commissioners of Patents, with his Petition, on
the 14th March 1863.
I, ROBERT ALEXANDER, of Islington, Liverpool, in the County of Lancaster,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
MARINERS' COMPASSES AND THE PARTS IN CONNECTION THEREWITH, AND IN THE
APPLICATION THEREOF TO MAGNETIC INSTRUMENTS," to be as follows, that is to
say:―
My Invention has for its object improvements in mariners' compasses and
the parts in connection therewith, as described in my Provisional Specification
of the 25th September 1862, N° 2611, and now repeated with such additions
and modifications as have been found necessary from lengthened experimental
trials for rendering the said Invention more complete.

page_text: The improvements consist in compensating or adjusting media, or both in
combination, to render the magnetic needle independant of the local attraction
of iron or other metal, metallic ores or compounds, in the ship, vessel, or other
place where the compass or needle is fixed or used.
The means by which I propose to effect the said improvements are,-
1st. Appliances of counteracting and adjusting magnets or magnetic poles
upon the compass needle card or cards, or otherwise placed as may be found
most effective in practice.
2nd. In the use, if necessary, of a moveable magnetic ring or rings attached
to the needle card by springs or otherwise so as to be easily removed when
required.
3rd. In the use of a series or number of magnets placed on a circular,
flat, or curved surface, with or without rims or bands of soft iron, stationary or
revolving, above or below, or horizontal, with the needle card or cards, or both,
above, below, and horizontally placed.
4th. In the application of electricity or galvanism in conjunction with a part
or the whole of the aforesaid appliances.
5th. In the use of one or more of the magnetic needle cards, and one or
more of the appliances of those explained above, placed one above the other,
revolving, in union or independant of one another, on the same or on distinct
pivots, or one or more of them stationary and another or others revolving, or
any one or more of these used in conjunction with a simple magnetic compass
card as commonly used, only revolving on distinct pivots whilst a part may be
stationary.
6th. In the use of alluminum metal for the needle cards, or india-rubber
composition commonly called ebonite, for the cards, rims, bowls, hoods, boxes,
binnacles, and gimballs, and other parts of the compasses and appliances, or an
admixture of steel filings or cuttings in the india-rubber composition for some
of these or the whole of the parts above referred to.
7th. In the use of hollow iron spheres or spheroids to encompass a part or
the whole of the apparatus.
'
8th. In the application of a spring, pivot, or point, on which the magnetic
compass card revolves, and springs to an outward or second gimball to the
bowl.
9th. In the application of my Invention to electric magnetic instruments.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert Alexander in the Great Seal Patent Office on the
14th September 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
ALEXANDER, of Islington, Liverpool, in the County of Lancaster, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of March, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Robert Alexander, Her special licence that I, the said Robert
Alexander, my executors, administrators, and assigns, or such others as I, the
said Robert Alexander, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time, and at all times
thereafter 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 MARINERS' COMPASSES AND THE PARTS IN CONNECTION THEREWITH, AND
IN THE APPLICATION THEREOF TO MAGNETIC INSTRUMENTS," upon the condition
(amongst others) that I, the said Robert Alexander, my executors or adminis-
trators, 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 Robert Alexander, do hereby
declare the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement (that is to say) :-
This Invention relates to improvements in mariners' compasses and the
parts in connection therewith, as described in my Provisional Specification
of the 25th September 1862, No. 2611, and as also further described in my
Provisional Specification of the 14th March 1863, No. 695, and now repeated
with such modifications as have been found necessary for rendering the said
Invention more complete.
The improvements consist in compensating or adjusting media, or both in
combination, to render the magnetic needle independant of the local attraction

page_text: of iron or other metals, metallic ores or compounds, in the ship, vessel, or other
place where the compass or needle is fixed or used. The means by which I
propose to effect the said improvements are,-
1st. Appliances of counteracting and adjusting magnets or magnetic poles
upon the compass needle card or cards, or otherwise placed as may be found
most effective in practice.
2ndly. In the use, if necessary, of a moveable magnetic ring or rings
attached to the needle card by springs or otherwise so as to be easily removed
when required.
3rdly. In the use of a series or number of magnets placed on or in a flat
or curved surface, with or without rims or bands of soft iron, stationary or
revolving, above or below, or horizontal, with the needle card or cards, or both,
above and below them.
4thly. In the application of electricity or galvanism in conjunction with a
part or the whole of the aforesaid appliances.
5thly. In the use of one or more of the magnetic needle cards, and one or
more of the appliances of those explained above, placed one above the other,
revolving, in union or independant of one another on the same or on distinct
pivots, or one or more of them stationary and another or others revolving,
or any one or more of these used in conjunction with a simple magnetic compass
card as commonly used, only revolving on distinct pivots whilst a part may be
stationary.
6th. In the use of alluminium metal for the needle cards, or india-rubber
composition commonly called ebonite, for the cards, rims, bowls, hoods, boxes,
binnacles, and gimbals, and other parts of the compasses and appliances, or an
admixture of steel filings or cuttings in the india-rubber composition for some
of these or the whole of the parts above referred to.
7th. In the use of hollow iron spheres or spheroids to encompas a part or
the whole of the apparatus.
8th. In the application of a spring pivot or point on which the magnetic
compass card revolves, and springs to an outward or second gimbal to the bowl.
9th. In the application of my Invention to electric magnetic instruments.
And the objects of my Invention are to make the mariners' compass and
the parts in connection therewith more effective and to cause the same to act
with more certainty than those of the ordinary construction, and possibly to
prevent the magnetic needle of the compass from being attracted by the iron
or other metals of or in the ship or vessel or place where the compass or
needle is fixed or used.

page_text: I propose to accomplish the said improvements by the compensating and
adjusting media herein described, either placed on the magnetic needle card
or cards, or with other compensators placed underneath, or above, or both under
and above, the card or cards, or around the whole apparatus, as may be found
necessary. And in order to explain my said Invention as completely as possible,
I now proceed to describe the last means I am acquainted with for carrying
the same into practical effect, reference being made to the accompanying
Drawing and to the numerical figures and letters of reference thereon respec-
11
necessary. And in order to explain my said Invention as completely as possible,
I now proceed to describe the last means I am acquainted with for carrying
the same into practical effect, reference being made to the accompanying
Drawing and to the numerical figures and letters of reference thereon respec-
tively as follows.
EXPLANATION OF THE DRAWING.
Fig. 1 is a view of the improved magnetic card or cards with its or their
adjusting and compensating magnets attached; N indicates the north poles;
S, the south poles. One card may be used in ordinary cases or where no
great attraction is found to exist, but in cases of greater attraction two or even
three cards may be used, the one underneath the other, but each revolving on
distinct or separate pivots and supported. on separate gimbals, making use
also, if found necessary, of one or more of the appliances represented in
Figs. 2, 3, 4, 5, and 6. a, a, a, is the principle magnetic needle; b, b, b,
are the adjusting and compensating magnets placed in position either as
shewn, or the magnets may be constructed of different forms and placed
in different positions upon the card or cards, as the attraction may require,
upon the same principle.
Fig. 2 is a view of an adjusting and compensating circular metalic rim with
magnets attached and made to move in slots cut in the rim; these magnets
may be 8, 12, 16, or more, according to circumstances; this rim is placed
round the edge of the card, with or without any of the adjusting media on
the card, according as may be found most effective. a, a, a, is the metallic rim ;
b, b, b, are the adjusting and compensating magnets, which are to be moved
and adjusted until the local attraction is thereby compensated. a', a', a', a¹,
are the slots cut through the rim in which the magnets are made to move.
Fig. 3 is a view of a series of magnets placed horizontally or at an angle,
according to circumstances, on a circular piece of wood, metal, or ebonite,
which may be used when required in connection with one or more cards with
or without the rim as may be found necessary; this apparatus is placed
underneath the card or cards. a is the circular piece of wood, metal, or
ebonite, with a hole in the centre. a, a, a, a', are the magnets in position;
N indicates the north poles, S the south poles.

page_text: Fig. 4 is a view of a nest of vertical magnets fixed in a cylinder of wood,
metal, or ebonite, to be placed above or under the card or cards, or even
above and below if found necessary. N indicates the north poles, S the south
poles; these poles may be reversed according to circumstances.
Fig. 5 is a view of the pivot and its appendages on which the compass card
revolves. a is a steel point; b is the metallic tube which is made to rise
and fall over another tube c, c, c, which passes through the bowl bearing
in its centre a vertical magnet d, d, d; e, e, is an india-rubber ball,
the
pierced through, which slips over the tube c, c, c, and rests on
shoulders h, h. a', a', and 61, 61, are two small rims fixed to the tube c, c, c,
to diminish friction.
Fig. 6. is the view of an iron circular globe to be made of such a size as
circumstances may admit from 4 to 8 feet diameter, to encompass the whole
apparatus. a, a, is the iron globe; b, b, are the feet on which it rests; c, c, c, is an
iron rail on which the feet rest, and made so that the two halves of the globe may
be run out or in as required; e, e, e, is a rebaited groove where the globe unites
in the centre of its vertical diameter. d, d, are two or more spring fastenings
adapted to these grooves to keep the whole together and to admit of their being
loosened into two separate parts when required; f.f, f, are apertures made to
give light; 9, 9, are screws which pass through the feet and into the rail; these
globes may be lined with wood, or felt, or india-rubber sheeting if required.
I now proceed to explain the nature of the other improvements of this
my Invention which are not illustrated in the Drawings, which consist, 1st,
in the use of india-rubber composition called "ebonite" for cards, bowls,
rims, gimbals, and other parts in connection with the compass.
"
2ndly. In the use of aluminium metal for compass cards and other parts
in connection, and I hereby further declare that I do not confine or restrict
myself in every case to the precise details described and shewn in the Drawings,
as variations of position and form of the compensating and adjusting magnets
which may be made and applied without departing from the principle of the
Invention, and that which I claim as my improvements to be secured to me in
the herein partly recited Letters Patent, are,―
F
First, the application of adjusting and compensating magnets, placed on the
compass card or cards, their forms, shapes, and .pósition being regulated as
required, or placed on a metallic rim to encompass the edge of the cards, or
placed below or above, or both above and below the cards as circumstances
may require.
2ndly. In the use of ebonite and aluminium metal as above described.

page_text: 3rdly. The use of the iron globe when necessary as illustrated; and
4thly. The use of the improved tube spring and moveable pivot con-
structed in the manner described and shewn for the purposes herein set
forth.
In witness whereof, I, the said Robert Alexander, have hereunto set my
hand and seal, this Fourteenth day of September, in the year of our
Lord One thousand eight hundred and sixty-three.
ROBERT ALEXANDER. (L.S.)
ROBERT ALEXANDER. (L.S.)