IMPROVEMENTS IN MEANS FOR RENDERING SHIPS' AND OTHER COMPASSES INSENSIBLE TO LOCAL ATTRACTION."
Year: 1863

page_text: LETTERS PATENT to John Sacheverell Gisborne, of Birkenhead, in the
County of Chester, Electrical Engineer, and William Simpson, of
Liverpool, in the County of Lancaster, Gentleman, for the Invention of
"IMPROVEMENTS IN MEANS FOR RENDERING SHIPS' AND OTHER COMPASSES
INSENSIBLE TO LOCAL ATTRACTION."
Liverpool, in the County of Lancaster, Gentleman, for the Invention of
"IMPROVEMENTS IN MEANS FOR RENDERING SHIPS' AND OTHER COMPASSES
INSENSIBLE TO LOCAL ATTRACTION."
Sealed the 10th August 1863, and dated the 14 February 1863.
PROVISIONAL SPECIFICATION left by the said John Sacheverell Gisborne
and William Simpson at the Office of the Commissioners of Patents,
with their Petition, on the 14th February 1863.
We, JOHN SACHEVERELL GISBORNE, of Birkenhead, in the County of Chester,
Electrical Engineer, and WILLIAM SIMPSON, of Liverpool, in the County of
Lancaster, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MEANS FOR RENDERING SHIPS' AND OTHER COMPASSES INSENSIBLE
TO LOCAL ATTRACTION," to be as follows:-
Our Invention consists of the use or employment of electricity to render
insensible to local attraction, or to overcome or countercheck the local influ-
ences which have so often and so seriously affected the magnetic needles in
ships' compasses. And although our said Invention. is more particularly
applicable to compasses to be used on board ship, it is not exclusively so
applicable, as it may be applied to or used with other compasses.
In carrying out our Invention we prefer to surround or encircle the compass
box by a semispheroidal or conical shaped net work or coil of a good conducting

page_text: metal, and through or over the said net work or coil passing a current or
several currents of electricity from an ordinary battery. The semispheroidal
or conical shaped net work or coil can most conveniently be placed in relation
to the compass in such a position that the rim or edge of it shall only be in a
line or thereabouts with the needle and it; the said semispheroidal or conical
shaped net work or coil may or may not be suspended from the gimbals or
other suspensory arrangement ordinarily in use."
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Sacheverell Gisborne and William Simpson in the Great
Seal Patent Office on the 13th August 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
SACHEVERELL GISBORNE, of Birkenhead, in the County of Chester, Electrical
Engineer, and WILLIAM SIMPSON, of Liverpool, in the County of Lancaster,
Gentleman, send greeting.
'
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of February, 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 us,
the said John Sacheverell Gisborne and William Simpson, Her special licence
that we, the said John Sacheverell Gisborne and William Simpson, our
executors, administrators, and assigns, or such others as we, the said John
Sacheverell Gisborne and William Simpson, our 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 "IMPROVEMENTS IN MEANS FOR RENDERING SHIPS' AND OTHER
COMPASSES INSENSIBLE TO LOCAL ATTRACTION," upon the condition (amongst
others) that we, the said John Sacheverell Gisborne and William Simpson,
our executors or administrators, by an instrument in writing under our, 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 we, the said John Sacheverell Gisborne and William

page_text: Simpson, do hereby declare the nature of our 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) :-
Our Invention consists of the use or employment of electricity to render
insensible to local attraction, or to overcome or countercheck the local influences
which have so often and so seriously affected the magnetic needles in ships'
and other compassés. And although our said Invention is more particularly
serviceable in compasses to be used on board ship, it is not exclusively so
applicable, as it may be applied or used to or with other compasses.
The best mode or arrangement with which we are acquainted for carrying
our said Invention "of the use or employment of electricity" for the purpose
above named, into effect, consists in passing a current of electricity from an
ordinary battery through a coil of insulated copper wire wound around a
hollow conical or semispheroidal compass box, or wound around a hollow
conical or semispheroidal shaped dish encircling the compass box. In
either of these arrangements the magnetic or compass needle rests on a centre
pin, or when there are more than one they are secured to the card or other
part, which rests on the pin in any usual way, at a short distance below a
straight line drawn horizontally across the upper termination of the said coil
and below the mouth or termination of the conical or semispheroidal shaped
box or dish, the leading features of construction of compasses at present in
use being retained.
To enable other persons to manufacture and bring compasses constructed
according to our Invention into prac cal use, we will now describe more
particularly the arrangements herein-before mentioned, and in doing so reference
will be made to the illustrative Sheet of Drawings herewith, in which Fig. 1
is a side elevation with part of the binnacle frame removed; Fig. 2 a vertical
section, and Fig. 3 a bird's-eye view, the cover being removed, all of a binnacle
and compass for use at sea, and with a conical shaped compass box. Figs. 4,
5, and 6, are similar views to Figs. 1, 2, and 3, of a binnacle and compass.
for use at sea, the ordinary compass box being encircled by and attached to
a semispheroidal shaped dish which supports the pin or centre point on which.
the needle or needles and the card are balanced. Fig. 7 is a perspective.
view.
In Figs. 1, 2, and 3, the same letters of reference denote the same parts..
a, represents the binnacle; b, the compass bow; c, the pin for carrying the-
needle d and card e; f, the compass box made of sheet copper or other
material into the conical shape shewn and supported on gimbals g, as in:
ordinary compasses. On the outer surface of the said conical compass box. f,

page_text: there are fastened, by soldering or otherwise, a number of projecting pins or
pieces h, which keep the insulated wires in their places around the said
compass box or cone f. The insulted wires are here shewn to be two in
number, but one only, or any larger number, may be employed; at j they are
connected, after sufficient slack has been left for free movement of the
compass, to and communicate with the battery k, shewn as of the ordinary
sand or sulphate of copper description, although any other kind of battery or
means of maintaining a continuous current of electricity would answer the
same purpose. The currents of electricity may be made to travel in any
direction, but in practice it is advisable, indeed almost indispensable, that the
currents should pass around the cone, and consequently horizontally around
and below the magnetic or compass needle or needles in opposite directions,
that is, the layer of insulated wire next the cone may have the electricity
passing in one direction whilst the layer over it may have the electricity
passing in the opposite direction, or two insulated wires with the positive
end of one and negative end of the other. laid together may, be, taken and
wound around the cone. ., the glass cover; m, shews a protecting covering
of gutta percha or other material preferably impervious to moisture.
In Figs. 4, 5, 6, and 7, like letters of reference denote the same parts.
a² represents the binnacle; b', the compass bow; c', the needle and card
carrier; d¹, the needle; e¹, the card; f¹, the compass box, the same as those
now in use, and to which is shewn attached the semispheroidal shaped dish or
vessel g', that both of them may be carried on or by the gimballs h¹; ¹, the
glass cover; j', the projecting pieces or pins; k¹, the insulated circuit wires
or conductors of the electricity set free in the battery ', to which they are
connected by the screws m¹; n', the gutta percha or other protecting
cover.
To arrange or set either of the apparatus above described for use it is only
necessary to connect the wires to the battery, when, if the insulation is good,
a continuous current of electricity will pass from one pole of the battery to
the other through the coil, and in so doing the effect is to counteract practically
all local attraction of the magnetic needle or magnetic needles in ships' and
other compasses and give a "true north pole."
Having now set forth the nature of our said Invention, and described the
best constructions and arrangements of parts with which we are at present
acquainted for carrying the same into effect, we would have it understood that
we do not confine ourselves to the use or employment of the apparatus herein
described, nor to the use or employment of any particular kind of apparatus
or material, but what we claim as our Invention is, the use of electricity,

page_text: howsoever obtained and applied, for rendering compasses or the magnetic
needles in ships' and other compasses insensible practically to local attraction,
convenient constructions and arrangements for carrying the same into effect
having been set forth in this Specification, and illustrated in the accompanying
Sheet of Drawings.
In witness whereof, we, the said John Sacheverell Gisborne and William
Simpson, have hereunto set our hands and seals, this Tenth day of
August, in the year of our Lord One thousand eight hundred and
sixty-three.
JOHN SACHEVERELL GISBORNE.
(L.S.)
WILLIAM SIMPSON.
(L.S.)
In the presence of
JOHN DAVIES,
Clerk to JOHN THOMSON KING,
Patent Agent,
4, Clayton Square,
Liverpool.