ELECTRICAL APPLIANCES FOR A MARINERS COMPASS TO GIVE ALARM UPON DEVIATION FROM THE SHIPS COURSE
Year: 1888

page_text: Deviation from the Ship's Course.
I AUGUSTUS GROSS of Newcastle in the Colony of New South Wales Nautical
Instrument Maker do hereby declare the nature of my Invention for ELECTRICAL
APPLIANCES FOR A MARINERS COMPASS TO GIVE ALARM UPON DEVIATION FROM THE
SHIPS COURSE and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:—
My invention consists of appliances forming part of a Mariners compass or attach-
ments thereto to sound an alarm or bell upon a deviation in steering from the ships
course according to instructions, the extent of the deviation it is desired to make
known, from a degree to two three or more points being determined by the adjustment
of portion of the apparatus.
My invention comprises the following features and appliances.
The insulation of the Compass bowl from the binacle.
The insulation from the coinpass bowl of the points or pivot of the compass on which
the card plays.
A hollow axle is fixed in the centre of the compass glass and a piece of brass
presenting somewhat the shape of a fork which I term a transmission fork and which
serves the purpose of a course setter is fitted thereon on the outside of the glass having
its ends resting on the rim or bezel of the Compass. The axle is carried down below
the glass to within about an inch of the Compass Card and on the end of the axle a
lower transmission fork is fixed radially in the same position with the upper trans-
mission fork. The ends of the lower transmission fork for a length of three and three
quarter inches are constructed of fine gold wires fixed so as to have an outward spring
and to reach the periphery of the Compass card. The wires pass through the grooves
of a slide and the perimeter ends of the wires are brought together or set apart by
means of the said slide operated by a pinion gear passing through the hollow axle
having attached thereto a racket adjustment parallel with the glass.
A piece of platinum wire is fixed at the north point of the Compass connected 'with
...

page_text: he magnetised bar or a magnetised cross bar of the Compass Card and the said wire is
bent so as to give the same spring power with the end pointing towards the glass the
same reaching about a quarter of an inch above the perimeter ends of the lower
transmission fork.
The cap of the Compass card is constructed of silver steel tempered to diamond
hardness.
A piece of platinum wire is soldered on the top and in the centre of the rim or bezel
of the Compass as an efficient conducting material.
The wires of a suitable battery are so connected with the compass bowl and an alarm
bell that when either of the wires of the lower transmission fork comes into contact
with the platinum wire at the North point of the compass the circuit will be
complete.
The wires of the lower transmission fork are brought together or set apart on each
side of the platinum wire on the North point to show on the Compass Card the desired
extent of deviation from the ships course so that upon such deviation taking place the
wires (completing the circuit) will come into contact and the alarm be sounded.
My invention is carried out by the mechanism illustrated in the accompanying
drawings in which on Sheet 1
Figure 1 represents the bowl of an ordinary Mariners Compass with all the
attachments thereto and connections with battery and single stroke electric bell.
Figure 2 is a plan of Figure 1 shewing viewed in that position the upper and lower
transmission forks and the electrical connections to the compass bowl.
On Sheet 2
Figure 3 is a view in section of the mechanical parts of the axle passing through
the glass of the compass.
Figure 4 is a plan of the underneath surface of the card or dial of a Mariners
Compass having a single bar magnet.
Figure 5 is a plan of a like card or dial having a compound bar magnet.
Figure 6 is a plan shewing the lower transmission fork below the glass of the
compass bowl and racket adjustment for same.
Like letters indicate the same parts throughout the drawings.
In Figure 1, A is the point or pivot of the Compass on which the Card plays of the
usual construction' with the exception that the same is insulated from the bowl, I effect
this by means of the washer a constructed of vulcanite or ivory which fits on the
outside of the bowl and around the point or pivot where the same passes through the
bowl, and also by the washer b constructed of like material fitted on the inside of
the bowl and in contact with the upper portion of the washer a around the point or
pivot. On the nut C of the point or pivot on the outside of the bowl I fix a small
brass binding screw d to which is attached a connecting wire e of one pole of a
battery which may be located in any convenient place as in a locker or the Captains
cabin.
I use preferably a Leclanché Battery consisting of four or more cells, according to
the size of the electric bell to be worked, but of course any other Battery suitable for
an alarm bell may be used. The other pole g of the battery is connected with one
clamping screw of the alarm bell B which can be located in any desired place as on
the bridge of the vessel. To the second clamping screw i of the bell is attached the
connecting wire j, the other end of which is attached to the small binding screw k on
the rim or bezel of the compass bowl.
A piece of platinum wire which need not be more than one thirty second of an
inch thick is soldered on the top and in the centre of the rim or bezel, to serve for the
more efficient conduct of the electric current which might be impeded by the oxydizing
of the brass.
The bowl of the compass is insulated from the binacle by small plates of vulcanite
or other nonconducting material of one eighth of an inch or other suitable thickness
placed between the sockets and the binacle for the gimbals of the compass to hang in.
I insulate the whole of the connecting wires before mentioned excepting the

page_text: enus attached to the screws, portions of the wires immediately in contact
with the compass bowl being slightly insulated, as a heavy insulated covering might
impede the swing of the bowl with the motion of the vessel. The best insulated
copper wire should be used as a protection against the action of salt water.
5 In Figure 2 C is the outer transmission fork or course setter outside the glass of the
compass bowl constructed of brass. I form the same with a width throughout of about
a quarter of an inch and a thickness of one sixteenth of an inch although these
dimensions are not material. The same is fitted tightly on the axle D and constructed
by means of an inclination from the centre forming a slight spring so that the points
rest firmly upon the compass rim or bezel, so as to make a good connection therewith.
D which is shown in section in Figure 3 Sheet 2 is the hollow axle passing through
the glass of the compass bowl. It is constructed with a collar to fit against the under
surface of the glass and it is fixed by means thereof and of the clamping nut E on the
outside of the glass. The upper transmission fork is fixed thereon between the said
clamping nut and the upper or outer clamping nut F. The said axle D is carried
down such length below the glass as to bring the lower end thereof about one inch
from the compass card or dial.
A spindle passes through the hollow axle D having on its lower end a pinion gear I
with a rack placed parallel with the glass the same being worked by means of the
mill headed nut K reaching above the clamping nut F. I drill a hole in the top of
the said nut K to receive the azimuth style or pin for nautical observations.
G is the lower transmission fork fixed on the axle D at the termination thereof and
therefore about an inch above the compass card or dial and radially in the same position
with the upper transmission fork C. The same is constructed by soldering at the end of
the axle a slip of brass about three quarters of an inch wide and about one sixteenth of an
inch thick and of sufficient length to bring the end thereof about four inches from the
periphery of the compass card and therefore varying in length with the diameter of
the compass. Upon the extreme end of the said slip of brass there are soldered two
wires one quarter of an inch apart of fine fifteen carat gold wire one sixty fourth of
an inch thick hard drawn. The said wires should be in all cases about three and
three quarter inches long so as to reach to the periphery of the Compass card. The
ends of the wires soldered on the brass are slightly curved so as to give the wires a
V shape and an outward spring. The distance of the perimeter or outside points of
the wires from each other when so fixed will necessarily vary but in a compass of the
dimensions shewn in the drawings eight inches in diameter the same when so fixed
vill give a distance of about two and three quarter inches apart as tho widest range.
One half of the space on the Compass Card between these points at the widest range
vill as presently shewn fix full extent of deviation from the course which the apparatus
s capable of shewing and the wires may possibly be adjusted so that the perimeter
oints may cover a wider space if desired. The wires of the transmission fork G are
serted in the two grooves of the slide H shewn in Figures 3 and 6. This slide is
perated by means of the spindle passing through the hollow axle D having on its
wer end the pinion gear I with the rack J to which the slide is attached placed
arallel with the glass, the same being worked by means of the mill headed nut K
aching above the clamping nut F. "When the slide H is close to the axle D it will
low the perimeter ends of the wires of the fork G to remain apart to the full extent
the space they are adjusted to cover when and as the slide is moved towards the
of the
compass,
timately allow of their being brought within about a quarter of an inch of each
brings the perimeter ends of the wires closer together and will
er which will cover two degrees on the card or dial of the compass shewn in the
awings.
At the north point of the compass card, a small brass screw m is fixed through the
gnetised bar of a single bar magnet compass as shewn in Figure 4, or in the
tre of the north cross bar of a compound bar magnet compass as shewn in
ure 5.
is a fine piece of platinum wire soldered on to such screw, bent as shewn in the

page_text: Drawing so as to give the same spring power and parallel with the surface of the glass
for about three fourths of an inch in length and then at right angles, so that the end
points towards the glass, and constructed so that the end reaches about a quarter of an
inch above the wires of the lower transmission fork G.
I construct the cap M in the Compass Card shewn in Figure 1 and Figure 3 to rest
upon the point or pivot of the compass of the best silver steel tempered to diamond
hardness and burnish the same into the brass mount in substitution as a conducting
material for the ordinary agate cap, but exactly of the same shape. And the same is
preferable. on account of its durability to the agate cap.
A disconnecting switch N is fixed at some point of the circuit. The same would
be of convenient use if fixed on the Bridge of the vessel. There may be more than
one disconnecting switch at different points if desired.
The apparatus is brought into operation by bringing the platinum wire L between
the wires of the lower transmission fork G. This is done by slightly lowering with
the hand the bowl of the Compass opposite the platinum wire L so as to raise the
perimeter ends of the lower transmission fork G above it and then turning the outer
transmission fork C and therefore with it the lower transmission fork & until the
platinum wire L is brought between the wires of the latter fork. The slide H is then
operated by the milled nut K until the perimeter ends of the wires of the transmission
fork G are brought within the distance of each other requisite to show the deviation
desired. Thus a distance showing two degrees on the compass card one on each side
of the platinum wire L will serve to indicate a deviation on either side, of one degree;
a distance of two points, a deviation on either side of one point &c.
If the ships.
course according to instructions is kept exactly by the steersman the platinum wire L
will remain exactly in the middle of the wires of the transmission fork G set at equal
distances on each side of it, but a deviation on either side to the extent to which the
fork is set will necessarily bring the platinum wire. L into contact with one of the
wires of the fork G and completing the circuit will sound the alarm bell which will
continue to ring so long as the contact remains, or every moment of the contact
being renewed by the oscillation of the steersman to the extent of the deviation.
In the event of its becoming necessary to alter the ships course suddenly before
the disconnecting switch could be used the wires of the transmission fork G would
spring over the platinum wire L without injury to the apparatus.
The desired object of checking the work of the steersman would be effected by the
use of the apparatus on a Bridge or standard compass out of the steersmans reach.
The alarm Bell could be fixed on the. Bridge within the hearing of the officer on
the watch or in any other convenient place and two bells could be affixed to the
apparatus if desired.
A Mariners Compass not manufactured with the said appliances could have the
same easily attached at a trifling expense by the additions and alterations thereto
indicated with the removal of the agate cap in the Compass card and the same being
replaced by the diamond tempered steel cap before mentioned.
Having thus particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. The apparatus hereinbefore described consisting of the mechanism formed by
the axle D passing through the Compass Glass having fitted thereon the outer
transinission fork or course setter C the lower transmission fork G regulated by the
slide H worked by the pinion gear I and rack J with the adjustment to the compass
card of the platinum wire L with the insulation of the compass point or pivot with
the insulation of the compass bowl from the binacle with the addition to the bezel or
rim of the platinum wire and the connection of such appliances with a battery and
alarm bell all substantially as shewn and described and for the purposes set forth.
2. The mechanism formed by the axle D passing through the compass glass. having
fitted thereon the outer transmission fork or course setter C with tlie addition to the

page_text: e platinu
slide H worked by the pinion gear J and rack J substantially as shewn and described
wire the lower transmission fork G regulated by the
and for the purposes set forth.
3. The lower transmission fork G substantially as shewn and described and for the
purposes set forth.
D
cover 1007.
A. GROSS.
Witness:
HENRY HIGHAN,
Clerk to Mr. A. De Lissa,
Solicitor,
Sydney.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.