Improvements in Compass and Sighting Attachments for Submergible and other Vessels.
Year: 1896

page_text: Date of Application, 11th July, 1896-Accepted, 6th Feb., 1897
COMPLETE SPECIFICATION.
Improvements in Compass and Sighting Attachments for
Submergible and other Vessels.
I, LOUIS GATHMANN, of 44 Lincoln Avenue, Chicago, Illinois, United States
of America, Mechanical Engineer, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
The object of this my invention is to obtain the greatest possible efficiency from
the modern compass.
With this end in view I obtain for it a relative freedom
from local magnetic influences, and thereby provide a reliable compass, particularly
for that class of vessels whose hulls can be wholly or partially submerged.
It is a well known fact that the compass is subject to great errors and not at
all reliable when placed in a submarine vessel below the water line or when near
masses of magnetic metal. I further provide telescopic sights, which in combination
with my compass, give the vessel a satisfactory manoeuvring capacity. That is to
say, any desired course can be maintained by the aid of said compass and the
position of an object-say, an enemy's ship, determined by the telescopic sights,
while the greater portion or even the entire hull of the vessel is submerged, the
vessel being thus protected by a body of water and therefore practically secure
from the fire of an enemy's guns.
I will describe my several improvements in connection with a partially sub-
mergible boat, such as is intended for torpedo service.
In the accompanying drawings:
Figure 1 is an elevation of a boat of the partially submergible class.
Figure 2 is an elevation partly in broken section through the conning tower
and upper deck.
Figure 3 is a plan view of the parts shown in Figure 2.
Figure 4 is a broken sectional elevation showing a compass and a method of
mounting the same.
Figure 5 is a similar view showing another form of compass.
Figure 6 is an elevation showing a form of swinging compass with an observation
telescope, and
Figure 7 is a broken sectional elevation showing one embodiment of my
telescopic sight.
In the accompanying drawings, let 8 represent the hull of a vessel which hull is
submergible, and which is provided near the upper deck line with port holes for
the guns 9. The upper deck is surmounted by a conning tower 10 shown in broken
elevation in Figure 2, and this conning tower is surmounted again by an enclosure 11,
protecting and supporting the compasses and telescopic sights, as also the stack 12
and ventilating pipes 13. Arranged preferably near the ends of the conning tower
and projecting through the enclosure surmounting it, I place my compasses, three
forms of which are shown in Figures 4, 5, and 6 respectively of the drawings.
The compass is elevated sufficiently above the deck to be out of the influence of
magnetic masses. In order to support the compass in this elevated position, I may
employ tubes or hollow masts 14, which in the form shown in Figure 4 are closed
at their upper ends by a cap 15, affording an enlarged lateral chamber 16 within
which the compass 17 is mounted.

page_text: In the construction shown in Figure 4, a binnacle, or modern ship's compass is
mounted with a light 18, arranged in proximity thereto, and a reflecting surface
such as the mirror 19 extending across the upper portion of the chamber to reflect
the reading of the compass down the tube. Within the lower portion of the
tube 14 is arranged the telescope 20, having the ordinary lenses 21, 22, therein, or
a single lens being provided. At the lower end of the tube is arranged a prism 23
and adjacent thereto the eye pieces 24; the telescope being of the usual con-
struction, and serving to magnify the image reflected from the mirror, and thus
enabling the compass to be easily read by a person stationed in the conning tower,
which may be wholly or partially submerged.
In the construction shown in Figure 5, a transparent compass 25 is employed,
being mounted within the upper end of a tube and a lamp 18 and reflector 19 are
used to assist in the reading; a telescope being arranged in the bottom portion of
the tube as in the previously described construction. The form of compass shown
in Figure 6 is particularly adapted for men-of-war of low free-board and the like
class of vessels. This construction is particularly designed to preserve the
magnetic centre of a compass on iron ships and to ensure greater steadiness of
the compass at sea in all weathers. The compass is placed within a hollow mast
or tube 26 which has a journal or trunnion 27 in a supporting post 28, extending
up alongside the bridge for convenience. The tube 26 may contain a compass of
the form shown in Figure 4, or of the form shown in Figure 5, or of any other
approved form, and said tube is provided, as shown, with a weighted extension 29,
depending below the pivotal support of the tube 26 and serving by its weight to
maintain the tube 26 in a perpendicular position, regardless of the pitching or
rolling of the vessel. This method of mounting relieves the compass from any
excessive motion, and consequent rapid wear of delicate parts, and therefore
ensures a steady compass card.
In this construction it will be observed that the eye piece 30 is arranged in a
line with the axis of the swinging tube, so that such eye piece does not change its
position when the tube moves out of aligument with its supporting post.
As a complement to the compass arrangement above described, and as a part of
the equipment of a vessel which is submergible, I employ telescopic sights which
enable the guns carried by the vessel to be directed toward any object within
range, although the gunner may be practically protected by the submerged part of
the vessel. These telescopic sights may be of any desired number and stationary
or capable of revolving as desired. Preferably one or more of them are made so
as to be revolved and thus to sweep the horizon. The telescopic sight comprises a
prism 31, mounted opposite a sight aperture 32 in a cap 33, on the upper end of a
tube 34, capable of revolving within the upper end of a supporting tube or cylindrical
frame 35 and operated by any suitable means, such as the rod or shaft 36 having
the gear wheel or pinion 37 meshing with a rack 38 on the periphery of the tube 34.
The supporting tube 35 extends down to the vicinity of the gunner's station and has
mounted in the lower end thereof a telescope 39 with the eye piece 40 accessible to
the gunner. The eye piece may be provided with the usual cross lines, which are
-commonly employed in telescopic sights.
By referring to Figure 2, it will be seen that I have provided three of such
revolving telescopic sights and have shown a stationary telescopic sight at 41.
When a series of these devices are employed, they will preferably project to
different heights, and by their duplication or multiplication, and also by varying
their heights, partial provision is made against the contingency of accident or
disabling which in case only one was employed would leave the ship without
adequate means for defence. Furthermore, by providing a plurality of these
telescopic sights, they may be so arranged as to be serviceable for a particular gun
or group of guns; the guns being usually stationary or commanding only a certain
sweep.
It will be seen that by means of these inventions, a satisfactory manoeuvring
capacity is given to a submerged or partially submerged war-vessel. When a view

page_text: of a distant object is obtained by means of the telescopic sights, the bearing of its
direction can be maintained by means of the compass as described; even though
the vessel and sights and compass be wholly submerged.
Having now 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. An improved compass attachment for submergible and other vessels consisting
of a tube or hollow mast extending through the deck of the vessel, a compass
situated in the upper end portion of said tube or hollow mast above the deck and
means for observing said compass, said means being located in the lower portion of
said tube or hollow mast below the deck.
2. An improvement in sighting attachments for submergible and other vessels
consisting of an upright sighting tube provided in its upper end portion with a
reflector and in its lower end portion with a telescope to receive the light reflected
therethrough, said upright tube having its observation end below the deck.
3. In a submergible vessel a plurality of rigid sighting tubes situated approxi-
mately midway between the ends of the vessel, said sighting-tubes varying in
height and provided at their upper end with reflectors and at their lower end with
telescopes, substantially as described.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.