AN IMPROVED APPARATUS FOR INDICATING THE VARIATION OF THE MAGNETIC NEEDLE
Year: 1852

page_text: LETTERS PATENT to Joseph Charles Frederick Baron de Klein-
sorgen, of Little New Street, in the City of London, for the
Invention of "AN IMPROVED APPARATUS FOR INDICATING THE
VARIATION OF THE MAGNETIC NEEDLE."
PROVISIONAL SPECIFICATION left by the said Joseph Charles
Frederick Baron de Kleinsorgen at the Office of the Commis-
sioners of Patents, with his Petition, on the 26th October 1852.
I, JOSEPH CHARLES FREDERICK BARON DE KLEINSORGEN, do hereby
declare the nature of the said Invention for "AN IMPROVED APPARATUS
FOR INDICATING THE VARIATION OF THE MAGNETIC NEEDLE" to be as
follows:-
The object of this Invention is to ascertain the amount of variation
in the magnetic needle from the true north on every part of the globe,
without the necessity of entering into elaborate calculations for obtain-

page_text: pro-
ing the result. To this end I construct a mariner's compass, and
suspend it so that it may receive an axial motion. The box of this
compass I compose of glass, (by preference, two thicknesses,) so that
the floating card will be visible through the side of the box. Upon
this box, and forming an upper compartment thereto, I mount a second
box containing a fixed compass card. As a cover for the box I
vide a lens which will concentrate the light upon the fixed card. A
vertical line is made on the outside of the compass box coincident with
the north point of the upper or fixed compass card, and when an obser-
vation of the variation of the needle is to be taken the compass must
be turned so as to bring the north pole of the floating compass also
into coincidence with that of the fixed card. Affixed to the upper box,
and placed immediately over the line of north and south on the upper
card, is a straight bar, which is intended to throw a shadow upon the
card, and thereby indicate, as will be presently explained, the direction
of due north and south.
With the instruments usually employed for taking the altitude of the
sun the exact noon time is to be found, and at the moment at which
this takes place it is to be seen whether the shadow of the bar falls
exactly on the south pole of the fixed card. When this is the case the
magnetic needle will point due north, but if the shadow falls either
towards the cast or towards the west the instrument must be turned
round on its vertical axis until the shadow falls exactly on the south
pole of the card, in which case the easterly or westerly variation
amounts to as many degrees as the difference between the north pole
of the needle and the vertical line on the outside of the box. This is
the whole operation, as quickly and easily performed as it is infallibly
correct.
The use of the lens is to concentrate the sun's rays in cloudy
weather, and obtain the required shadow.
The space left between the two glass cylinders which form the lower
division of the compass box is intended to prevent the local attraction
of the needle.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Charles Frederick Baron de Kleinsorgen
in the Great Seal Patent Office, on the 26th April 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, 1,
JOSEPH CHARLES FREDERICK BARON DE KLEINSORGEN, of Little New
Street, in the City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-sixth day of October, in the
year of our Lord One thousand eight hundred and fifty-two, in the six-
teenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Joseph Charles Frederick Baron de
Kleinsorgen, Her special licence that I, the said Joseph Charles
Frederick Baron de Kleinsorgen, my executors, administrators, and
assigns, or such others as I, the said Joseph Charles Frederick
Baron de Kleinsorgen, 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 King-
dom of Great Britain and Ireland, the Channel Islands, and Isle of
Man, an Invention for "AN IMPROVED APPARATUS FOR INDICATING THE
VARIATION OF THE MAGNETIC NEEDLE," upon the condition (amongst
others) that I, the said Joseph Charles Frederick Baron de Kleinsorgen,
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, 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 Joseph Charles Frederick Baron
de Kleinsorgen, 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 thereof,
reference being had to the Drawing hereto annexed, and to the figures
and letters marked thereon, that is to say:
The Invention consists in ascertaining the variation of the magnetic
needle from the true north on every part of the globe.

page_text: Figure 1, is a front view of the apparatus.
Figure 2, a section showing the internal structure.
Figure 8, is the ordinary compass card.
Figure 4, the fixed card for correcting the variation.
Figure 5, shews the apparatus in a portable case.
Figure 6, shews the indicator placed on the fixed card.
The apparatus is constructed in the form of a compass hanging in the
arc n, n, which is suspended in the frame o, o, giving it an oscillatory
movement each way, while another horizontal central movement is pro-
duced by means of the axis. p. a, a, and a³, a', are two glass cylinders,
arranged one within the other, and fixed in their corrresponding mount-
ings i, i, and k, k, in such a manner as to leave an empty space between
the glass cylinders a, and a¹. c, c, is a common compass card which,
with the needle fastened on it, moves on the point s. On the ring i, i,
another corresponding ring 1, l, is screwed, which also contains a glass
cylinder b, b, at the upper end of which there is fastened a fourth brass
ring q, q, by which the Instrument is attached to the arc n, n, by the
screws v, v.
If desired, the upper half of the instrument can be made of metal.
e, is a lens, the mounting f,f, of which forms at the same time the lid
of the upper cylinder. p, p, is a brass bottom, which separates the two
cylinders.. d, d, is a second brass bottom with an immovable compass
card, but without a needle fastened on it. The bottom d, d, is fastened
by means of a screw m, as also the axis t, on which the registers g, and
g', turn.
The indicator shown in Figures 1, and 6, has at one end a hinge,
which is put into the groove u, on the upper ring q, q, of the
cylinder b, b.
The method hitherto pursued for finding the variation has been to
start from the magnetic north in the north pole itself. Now by my
improvements I start from an invariable absoluto point, that is to
say, the south pole, which indicates the north positively and infallibly.
The operation of the instrument is as follows:-On the outside of the
compass from the ring q, q, to the ring k, k, there is a-straight vertical
line in the middle of the arrow to. Exactly in the same direction with

page_text: this line is the north pole of the permanent compass card D, D, and
by commencing the operation, which must always be done at mid-day
exactly, the compass must be turned in such a manner as to have the
north pole of the compass card C, C, corresponding with the said line
exactly. If the sky is favorable the lid F, F, with the lens E, are
taken off, not being in that case required for the operation, and the end
N, of the needle is put into the groove V, so that the needle lies hori-
zontally over the glass cylinder B, B, exactly in the direction of the
north and the south pole of the compass card D, D.
With the instruments usually employed for that purpose (Octant, &c.)
the exact noon time is found, and the moment at which this takes place
it must be observed whether the shadow of the needle falls exactly on
the south pole of the card D, D. If this is the case the magnetic
needle is right, but if the shadow falls either towards the east or the
west the body of the instrument must be turned round on its vertical
axis until the shadow falls exactly on the south pole of the card A, A,
in which case the easterly or westerly variation amounts to as many
degrees as the difference between the north pole of the needle and the
point of the vertical arrow V, on the outside of the box.
Should the sun be obscured, and no well-defined shadow to be
obtained, the lens must be employed in order to concentrate its rays.
The registers G, G', form a desired number of compartments, into
which small slips of parchment are put, with the variation found under
any meridian written on them, and serves to give to the navigator an
easy method of inspecting the variations found, but the instrument can
be made without these registers, if desired. The space left between the
two glass cylinders A, A, and a', a', being a vacuum, is for preventing
the local attraction of the needle in so far as it is necessary for com-
mon use, and, if desired, a still higher degree of insulation can be
established.
There can be also added, if particularly required, a universal sun-
dial, or a method of addition by the moments of the rising and setting
of the sun, and likewise a method of addition for various lunar
altitudes.

page_text: The instrument can also, if desired, be brought in connection with
the steering compass.
This instrument can also be provided with a pedestal for hydrogra-
phical, topographical, land, and other surveying operations.
And having thus described the nature of my said Invention, and the
manner in which the same is to be carried into effect, I wish it to be
understood that I do not restrict myself to the precise details herein-
before described. But what I claim as new, and intend to be protected
by the herein-before in part recited Letters Patent, is,―
Firstly, the improved apparatus for finding the variation of the 1
magnetic needle from the north by means of the south pole.
Secondly, the finding of this variation even when the sun is obscured.
Thirdly, the horizontal central movement of the compass.
In witness whereof, I, the said Joseph Charles Frederick Baron de
Kleinsorgen, have hereto set my hand and seal, this
day of April, in the year of our Lord One thousand eight hun-
dred and fifty-three.
1
JOSEPH CARL TREDERIC BARON
DE KLEINSORGEN.
(L.S.)