AN IMPROVED METHOD OF ARRANGING AND APPLYING MAGNETS TO COUNTERACT OR COMPENSATE FOR THE EFFECTS OF LOCAL ATTRACTION ON THE MARINER'S COMPASS
Year: 1858

page_text: LETTERS PATENT to William Edward Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Civil Engineer, for the
Invention of "AN IMPROVED METHOD OF ARRANGING AND APPLYING MAGNETS
TO COUNTERACT OR COMPENSATE FOR THE EFFECTS OF LOCAL ATTRACTION ON
THE MARINER'S COMPASS."-A communication.
Sealed the 14th January 1859, and dated the 9th August 1858.
PROVISIONAL SPECIFICATION left by the said William Edward Newton
at the Office of the Commissioners of Patents, with his Petition, on
the 9th August 1858.
I, WILLIAM EDWARD NEWTON, of the Office for Patents,, 66, Chancery
Lane, in the County of Middlesex, Civil Engineer, do hereby declare the
nature of the said Invention for "AN IMPROVED METHOD OF ARRANGING AND
APPLYING MAGNETS TO COUNTERACT OR COMPENSATE FOR THE EFFECTS OF LOCAL
ATTRACTION ON THE MARINER'S COMPASS," to be as follows:-
The nature of this Invention consists in the arrangement of one or more
magnets in a horizontal position or positions below or above the needle of the
compass with opposite poles horizontally in line with the vertical centre or
axis on which the needle turns, and on opposite sides thereof, by which
arrangement the opposite poles of the magnet or magnets are caused to act

page_text: upon the needle to force it into the same direction. It also consists in
applying the so arranged magnet or magnets in such manner as to make it
or them adjustable on a centre, coinciding as nearly as practicable with the
vertical axis on which the needle turns, so that their poles may be made to
point in any direction necessary to compensate for the local attraction, and
may have their direction varied to meet any variation in the point or points
of local attraction that may be produced by different cargoes or by other
causes. And it further consists in providing for the adjustment of the so
arranged and applied magnets in a direction parallel with the axis or vertical
centre on which the needle works, for the purpose of increasing or diminishing
the intensity of their action according to the intensity of the local attraction.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Edward Newton in the Great Seal Patent Office
on the 8th February 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the County
of Middlesex, Civil Engineer, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of August, in the year of our Lord One
thousand eight hundred and fifty-eight, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Edward Newton, Her special license that I, the said William
Edward Newton, my executors, administrators, and assigns, or such others as
I, the said William Edward Newton, 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 "AN IMPROVED METHOD OF ARRANGING AND APPLYING MAGNETS TO COUNTER-
ACT OR COMPENSATE FOR THE EFFECTS OF LOCAL ATTRACTION ON THE MARINER'S
COMPASS," being a communication from abroad, upon the condition (amongst
others) that I, the said William Edward Newton, by an instrument in writing
under my hand and seal, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be performed,

page_text: 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 William Edward Newton, do hereby
declare the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the Drawing hereunto annexed.
and to the letters and figures marked thereon (that is to say):-
:―
This Invention of "An Improved Method of Arranging and Applying
Magnets to Counteract or Compensate for the Effects of Local Attraction on
the Mariner's Compass," consists in the arrangement of one or more magnets
in a horizontal position or positions below or above the needle of the compass,
with opposite poles horizontally in line with the vertical centre or axis on
which the needle turns, and on opposite sides thereof, by which arrangement
the opposite poles of the magnet or magnets are caused to act upon the
needle to force it into the same direction. It also consists in applying the
so arranged magnet or magnets in such a manner as to make it or them
adjustable on a centre coinciding as nearly as practicable with the vertical
axis on which the needle turns, so that their poles may be made to point in
any direction necessary to compensate for the local attraction, and may have
their direction varied to meet any variation in the point or points of local
attraction that may be produced by different cargoes or by other causes.
And it further consists in providing for the adjustment of the so arranged and
applied magnets in a direction parallel with the axis or vertical centre on
which the needle works, for the purpose of increasing or diminishing the
intensity of their action according to the intensity of the local attraction.
The accompanying Drawing represents the Invention applied to a binnacle
in such a manner as to make it constitute what may be termed a com-
pensating binnacle.
Fig. 1 is a vertical section of the binnacle, Fig. 2 is a plan of the same,
Fig. 3 is a plan of the lower part of the same and the magnets, Fig. 4 is a
plan view of a modified arrangement of the magnets. Similar letters of.
reference indicate corresponding parts wherever they occur in the several
Figures. A (Figures 1, 2, and 3) is the base of the binnacle, and B, C, is a
pillar erected thereon to support the bowl D, in which the compass may be
suspended in a gimbal in the usual manner; a is the magnetic needle, having
the card attached. The pillar B, C, and bow! D may be of wood, brass, or
composition metal. The pillar B, C, is made in two parts, and is secured.
E

page_text: together by a central bolt c, which also secures the bowl to them. The lower
portion B of the pillar is made hollow to constitute a box to contain the com-
pensating magnets, and it is open at the bottom and fitted into a recess in the
top of the base, and is secured by screws d, d, at the sides. F is a long
spindle, having on its exterior a screw thread, which screws through the centre
of the top parte of the base, and is arranged in such a position that when
the binnacle is perfectly upright its axis will coincide or be in line with the
vertical centre or axis upon which the needle turns. To this spindle F the
compensating magnet or magnets is or are attached. The Drawing repre-
sents two compensating magnets G, H, consisting of straight flat bars; one,
G, being permanently secured to the top of the spindle, and the other one, H,
having a hole through it, which is screwed internally to fit to the thread of
the spindle, and permit it to be adjusted higher or lower thereon, and nearer
to or further from the upper one, G. I is a jam nut on the spindle F for
securing the magnet H in any position. The spindle F has a head or handle
at its lower extremity by which to take hold of to turn it to make the
magnets point in any direction, and to raise and lower both together, so as to
bring them nearer to or further from the compass. J is a jam nut fitted to
the screw thread of the spindle F below the head e, e, of the base, and is
intended to secure the screw by being screwed up against the bottom of the
said head e, e. An opening should be provided in the base to admit a person's
hand to manipulate the spindle F and nut J.
What is meant in the before-mentioned statement of the nature of this
Invention by the arrangement of the magnets with their poles horizontally in
line with the vertical centre or axis of the needle or needles, will be under-
stood by referring to Fig. 3, in which two red lines g and h are drawn
through the centre of the spindle F, which coincides with the vertical centre
or axis of the needle. These red lines, it will also be seen, pass through the
poles of the two magnets respectively, through G, and h through H. It
will be also understood that by the well-known law in magnetism, which
causes like polarities to repel, and opposite polarities to attract each other,
both poles of either magnet thus arranged-will-act-upon-the-needle_with_
similar effect, that is to say, with a tendency to bring the south pole of the
needle over the north pole of the magnet, and vice versa.
The adjustment of the magnets G, H, to compensate for local attraction is
effected as follows:-The local attraction being apparent, its seat or the
direction thereof is ascertained by the usual or any suitable method, and it
must also be ascertained whether it attracts the north or south pole of the

page_text: needle. If the said attraction be all towards one point, as is most frequently
the case, the magnets G, H, of which there may be any number, must all be
adjusted to point the same way, or with their north poles all in the same
direction, and vice versa, so as to constitute in effect a single magnet, which
is all that is really necessary in this case, and thus secured to the spindle.
The spindle is then turned till the horizontal line passing through its centre
and through the poles of the magnets is directed towards the point of attrac-
tion or to a point in the same vertical line, the north pole being set towards
the said point if the local attraction is for the north pole of the needle, or
vice versa. If the north pole of the needle does not then point in the true
direction, it is because the action of the magnets is either not sufficiently
intense or too much so, and the spindle is raised or lowered by screwing it up
or down to increase or diminish the intensity of the action of the magnets
till, when they are directed, as above mentioned, to the point of local attrac
tion, the needle will indicate truly; and the spindle being then secured by
the nut J, the compensation for the local attraction thus effected will be true
in all positions of the vessel, which is seldom the case when the compensation
is effected by magnets arranged entirely at the side or sides of the compass:
In case the local attraction is toward two or more different points the adjust-
ment is more difficult, as the said points having to be ascertained, and the
relative intensities of the attraction ascertained, one or more magnets have to
be directed in the manner above described towards each point, and then
adjusted higher or lower till the degree of compensation is perfect and the
needle points in the true direction.
Fig. 4 represents the arrangement of the magnets in pairs instead of singly,
as represented in Figures 1, 2, and 3. The two straight-bar magnets K, K,
constituting the pair, are arranged parallel with each other side by side, with
their north poles both pointing in the same direction, and are connected
together rigidly by a cross bar L of brass or other unmagnetic metal, which
bar is attached at the centre of its length or exactly midway between the
magnets to the spindle F in the same manner as either of the magnets G, H.
These magnets must be also so arranged that the north pole of each and the
south pole of the other are in the same horizontal line with the centre of
the spindle F, as shewn by the red lines h, k, Fig. 4. Instead of a pair, a
connected in the same
set consisting of a greater number of magnets may be
way, an equal number on each side of the spindle, but they must be so
arranged that the north pole of each will be in the same horizontal line
passing through the centre of the spindle as the south pole of another. A

page_text: central magnet placed between the pair or pairs, and arranged midway
between them, and relatively to the spindle, like G or H, may be used in
combination with a pair or set applied like K, K. In case of pairs or sets
of pairs of magnets being used, arranged in this way, they are so set for
compensation that both or all are parallel with a line passing through the
centre of the spindle toward the point of local attraction. Though it is
preferable, either with the singly arranged magnets represented in Figures 1,
2 and 3, or with the modified arrangement in pairs or sets, as illustrated in
Fig. 4, to have the spindle F attached at or opposite to the centre of the
length of the magnets, this is not absolutely necessary.
For a "tell-tale" compass substantially the same mode of applying the
magnets may be adopted; but it might be preferable to arrange them above
instead of below the compass, which latter is the most convenient arrange-
ment for a binnacle compass.
The arrangement of and mode of applying the magnets, herein described,
not only affords much greater convenience for adjusting the compensation
than when the magnets are arranged at the side or sides of the compass; and
affords a more correct compensation for all positions of the vessel; but, pro-
vided the magnets are arranged at the same distance from the needle, their
effect is greater than that of magnets of corresponding power arranged at the
side or sides of the compass by reason of their double action (that is to say,)
the action of the opposite poles upon the needle both with a tendency to move
it in the same direction, and their arrangement in lines directly towards or
parallel with lines directed towards the point of local attraction.
Having now described the Invention that has been communicated to me by
my foreign correspondent, and having explained the manner of carrying the
same into effect, I would observe that I do not mean or intend to confine
myself to the precise arrangement of the magnets within a binnacle, as herein
shewn and described; but what I claim as new and desire to secure by
Letters Patent, is,
First, the arrangement of one or more magnets in a horizontal position or
positions-below-or-above-the-needle-or-needles-of_the_compass_with_opposite
poles horizontally in line with the vertical axis or centre on which the needle
turns and on opposite sides thereof, whether placed in a binnacle or otherwise,
for the purpose set forth.
Second, I claim so applying the so arranged magnet or magnets as to make
it or them adjustable on a centre, coinciding as nearly as practicable with the
vertical axis on which the needle turns, so that their poles may be made to

page_text: point in any direction necessary to compensate for the local attraction, and
have such direction varied as may become necessary.
Third, I claim providing for the adjustment, of the so arranged magnets in
a direction parallel with the axis or vertical centre on which the needle works,
for the purpose set forth.
In witness whereof, I, the said William Edward Newton, have hereunto
set my hand and seal, the Twenty-eighth day of January, in the
year of our Lord One thousand eight hundred and fifty-nine.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
W. E. NEWTON. (L.S.)