IMPROVEMENTS IN ARRANGING AND MOUNTING SHIPS' COMPASSES TO PREVENT LOCAL ATTRACTION
Year: 1874

page_text: LETTERS PATENT to Herbert John Such, of Tottenham, in the County
of Middlesex, for the Invention of "IMPROVEMENTS IN ARRANGING AND
MOUNTING SHIPS' COMPASSES TO PREVENT LOCAL ATTRACTION."--A com-
munication from abroad by Felix Henry Benary, Thomas T.
Anthony, and Carl Heinrich E. Seimunds, all of Hong Kong,
China
PROVISIONAL SPECIFICATION left by the said Herbert John Such at
the Office of the Commissioners of Patents, with his Petition, on
the 14th October 1874.
I, HERBERT JOHN SUCH, of Tottenham, in the County of Middlesex,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN ARRANGING AND MOUNTING SHIPS' COMPASSES TO PREVENT LOCAL ATTRACTION,"
(communicated to me from abroad by Felix Henry Benary, Thomas T.
Anthony, and Carl Heinrich E. Seimunds, all of Hong Kong, China,)
to be as follows :-
In arranging and mounting ships' compasses in accordance with this

page_text: Invention, the first and most important object has been to select a good
and trustworthy instrument, which when not brought into too close a
contact with metals of like affinity will not deviate more from the true
magnetic north than is occasioned by the friction of the needle on pivot
and other uavoidable imperfections of such instruments. After long
and careful investigation the conclusion come to is that compasses with
single needles properly balanced on jewelled pivots are for the purposes
of this Invention the most suitable ones.
Although spirit compasses are more sensitive, less liable to oscillations,
and in general better adapted for sea use than any other compasses, still
the very nature of the medium used for steadying the compass, the
spirits of wine, makes the same if not useless quite inappropriate for the
purpose of this Invention.
Being fully aware that the exclusion of spirit compasses will prevent
this improved method of mounting compasses from becoming generally
used for mounting steering compasses, still the exclusion of those kinds
of instruments from this improved system of galvanic isolation is
unavoidable, the object of this Invention being not so much to construct
steering compasses, as the very bulk and size of these improved instru-
ments excludes them from such use, but simply to produce standard
compasses which will remain unaffected by the local attraction of the
vessel in which they are used and therefore always show the true
magnetic north.
Having therefore selected a good single needle compass (by a reliable
maker) properly balanced and swinging in double gimbals in an oak,
cedar, or other suitable box, the same is placed in a square zinc box
leaving a clear space of at least 2 inches or thereabouts between the
bottom and sides of the zinc and wooden box, and overtopping the
latter by one inch or thereabouts. The thickness of the material used in
in the zinc box should not be less than 1 of an inch or thereabouts.
The space between the wood compass box and the zinc box is filled up
with powdered charcoal (vegetable) slightly sprinkled with a solution of
alum water, the charcoal being closely compressed and filled up to
the upper rim of the compass box.
On the outside of the zinc box there are 3 half round insertions
extending from the upper rim of the box down one side, leading under-
neath the bottom and up on the opposite side. These insertions which

page_text: are concave in shape are to receive 3 glass tubes of ¼ to ½ inch
diameter, varying in size in accordance with the size of the compass, the
glass tubes overtopping the sides of the zinc box by six inches or
thereabouts. These are secured by zinc brackets soldered to the zinc
box to keep the glass tube steady in their places.
On the four corners of the zinc box at an angle of 45 degrees, zinc
plates are soldered, extending 2½ inches or thereabouts from the side,
and likewise two on each side. At the distance of ½ of an inch there
are small perforations in these zinc plates. Four zinc plates of the same
size cross diagonally the bottom of the box, having the same perforations
at the same distance of one-eighth of an inch or thereabouts from one
another. A fine copper wire (of the most soft and pliable kind) is rove
through the holes in the zinc plates, commencing at the bottom and
ending on the top, the two ends being united and forming thereby an
endless chain. The whole apparatus is placed into a box made of oak,
teak, malawa, or other suitable material, which leaves again a clear
space
of 3 inches or thereabouts between the sides of the zinc box and
the outer box, bottom of uprights, and overtopping the zinc box by 1
inch or thereabouts. The inside of this outer box is lined with woollen
cloth (green with advantage), or other suitable material to the thickness
off of an inch or thereabouts, and this again is protected (sides and
bottom) by glass plates of ½ inch or thereabouts in thickness, fitting
closely in their joints and cemented together. In fact a closely fitting
complete glass case is most advantageous and should be tightly fitted
into the outer box.
Thin leaves of tinfoil are pasted over the glass plates up to within
2 inches or thereabouts of the top. The space between the zinc box and
the glass plates covered with tinfoil being not less than 2%, of an inch,
is now filled up with finely powdered glass closely compressed, and
covering completely the copper wire and forming a compact and solid
mass. It is then completely saturated with the following solutions, viz.,
normal sulphuric acid, muriatic acid, normal ether, and distilled water.
In putting in this solution particular pains have to be taken that all
parts of the powdered glass are equally saturated. The temperature of
the battery should not become more than 160° Fahrenheit. The top of
the glass is again covered with thin strips of tin foil, and clean cotton

page_text: closely compressed is placed both over the charcoal and glass. A square
wood top made of hard wood (advantageously of oak, teak, or malawa),
is placed on the top of the inner and outer box, having an aperture in
the middle large enough to show the face of the compass, it is then
securely screwed down with copper screws to the inner and outer boxes,
and the close fitting seams are covered with strips of cloth saturated
with a solution of gutta percha. The top has six holes corresponding
to the glass tubes, giving egress to the same. The glass tubes are now
filled up with a solution of sal ammoniac, common salt, and distilled
water to cool the battery.
In the construction of the compass surrounding batteries no other
materials than those mentioned should be used, iron and brass have to
be carefully avoided in making the boxes.
This improved method of arranging and mounting ships' compasses as
previously described may be safely put on board of any craft without any I
danger of fire or explosion. The filling or charge of the batteries will
last for 5 or 6 years, and a compass arranged and mounted in this
improved manner will not be effected by local attraction, and although
sluggish in its motions will even under the most unfavorable atmospheric
circumstances return to the true magnetic north within three minutes 2
time. From this true magnetic north by deducting the variation the
true north may be readily ascertained.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Herbert John Such in the Great Seal Patent
Office on the 14th April 1875.
"
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HERBERT
JOHN SUCH, of Tottenham, in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of October, in
the
year of our Lord One thousand eight hundred and seventy-four, in
the thirty-eighth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Herbert John Such, Her

page_text: special license that I, the said Herbert John Such, my executors,
administrators, and assigns, or such others as I, the said Herbert John
Such, 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 Inven-
tion for 66
IMPROVEMENTS IN ARRANGING AND MOUNTING SHIPS' COMPASSES TO
PREVENT LOCAL ATTRACTION," (a communication to me from abroad by
Felix Henry Benary, Thomas T. Anthony, and Carl Heinrich E.
Seimunds, all of Hong Kong, China,) upon the condition (amongst
others) that I, the said Herbert John Such, my executors or admini-
strators, 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 Herbert John Such, 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, that is to say :-
In arranging and mounting ships' compasses in accordance with this
Invention, the first and most important object has been to select a good
and trustworthy instrument, which when not brought into too close a
contact with metals of a like affinity will not deviate more from the true
magnetic north than is occasioned by the friction of the needle on pivot
and other unavoidable imperfections of such iustruments. After long
and careful investigation the conclusion come to is that compasses with
single needles properly balanced on jewelled pivots are for the purposes
of this Invention the most suitable ones.
Although spirit compasses are more sensitive, less liable to oscillation,
and in general better adapted for sea use than any other compasses, still
the very nature of the medium used for steadying the compass (the
spirits of wine), makes the same if not useless quite inappropriate for
the purpose of this Invention.

page_text: On the four corners of the zinc box B, at an angle of 45 degrees, zinc
plates B' are soldered, extending 2½ inches or thereabouts from the the
side, and likewise two on each side. At the distance of 1, of an inch or
thereabouts there are small perforations in these zinc plates. Four zinc
plates of the same size cross diagonally the bottom of box having
similar perforations at the the same distance of of an inch or there-
abouts from one another. A fine copper wire C (of the most soft and
pliable kind) is rove or passed through each of the holes in the zinc
plates B' commencing at the bottom and ending on the top, the two
ends being united and forming thereby endless chain or connection.
The whole apparatus is placed into a box D made of oak, teak, malawa,
or other suitable material which leaves again a clear space D' of 3
inches or thereabouts between the sides of the zinc box B and the outer
box D same on the bottom part of zinc box B and overtopping the zinc
box by 1 inch or thereabouts. The inside of this outer box D is
lined with woollen cloth (green with advantage) or other. suitable
material to the thickness of 16 of an inch or thereabouts, and this again
is protected (sides and bottom) by glass plates of inch or thereabouts
in thickness, fitting closely in their joints and cemented together. In
fact a closely fitting complete glass case is most advantageous, and
should be tightly fitted into the outer box D.
Thin leaves of "staniol," tinfoil, or other suitable material of similar
substance are pasted over the glass plates up to within two inches or
thereabouts of the top. The space between the zinc box B and the glass
plates covered with "staniol," tin foil, or other suitable material of similar
substance, which form a lining to the outer box D, being not less than
2 of an inch, is now filled up with finely powdered glass closely com-
pressed, and covering completely the copper wire, and forming a compact
and solid mass; it is then completely satured with the following
solution, videlicet, normal sulphuric acid 8 per cent, normal muriatic
acid 5 per cent., ether 15 per cent., and distilled water 85.5 per cent., or
thereabout of each ingredient. In putting in this solution particular
pains have to be taken that all parts of the powdered glass are equally
satured. The temperature of the battery should not become more than
160° Fahrenheit. The top of the glass is again covered with thin strips
of "staniol," tin foil, or other suitable material of similar substance, and
clean cotton closely compressed is placed both over the charcoal and

page_text: :
glass. A square wood top made of hard wood, advantageously of oak,
teak, or malawa, or any other suitable material is placed on the top of
the inner and outer boxes, having an aperture in the middle large
enough to show the face of the compass, it is then securely screwed
down with copper screws to the inner and outer boxes, and the close
fitting seams are covered with strips of cloth saturated with a solution of
gutta percha. The top has six holes corresponding to the glass tubes,
giving egress to the same. The glass tubes are now filled up with a
solution of sal ammoniac 8 per cent., common salt 12 per cent., and
distilled water 80 per cent. or thereabout to cool the battery.
In the construction of the compass surrounding batterys no other
materials than mentioned should be used. Iron and brass have to be
carefully avoided in making the boxes.
This improved method of arranging and mounting ships' compasses
as previously described, may be safely put on board of any craft without 1
any danger of fire or explosion. The filling or charge of the battaries
arranged and mounted in this improved manner will last for five or six
years, and the compass will not be affected by local attraction, and
although sluggish in its motions will even under the most unfavorable
atmospheric circumstances return to the true magnetic north within 2
three minutes time. From this true magnetic north by deducting the
variation the true north may be readily ascertained.
Figures 4 and 5, Sheet 2, show two views of a compass mounted,
surrounded, and isolated by a galvanic battery in a similar manner to
that previously described, in accordance with this Invention, in which 2
arrangement a fine platina wire C¹ passes through each of the tubes B³,
the ends of the said platina wires being led from the mouth of each
tube to the central point C³, where they are all united or connected
together.
Having thus described the nature of this Invention and the manner of g
carrying the same into practice, it should be clearly understood that the
Invention is not confined to the exact details herein described, so long
as the principal features of these improvements are retained, but what I
claim on behalf of my foreign correspondents is, the improved method of
arranging and mounting ships' compasses by surrounding and isolating 3
them by means of a galvanic battery constructed and arranged, sub-

page_text: stantially in the manner and for the purpose herein-before described and
represented in the Drawings annexed.
In witness whereof, I, the said Herbert John Such, have hereunto
set my hand and seal, this Thirteenth day of April, in the year
of our Lord One thousand eight hundred and seventy-five.
Witness,
J. G. TONGUE,
Patent Agent,
34, Southampton Buildings,
Chancery Lane,
London, W. C.
H. J. SUCH. (L.S.)