IMPROVEMENTS IN SHIPS' LIGHTS AND APPARATUS CONNECTED THEREWITH FOR SIGNALLING THE COURSE OF VESSELS
Year: 1879

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS
IN SHIPS' LIGHTS AND APPARATUS CONNECTED THEREWITH FOR SIGNALLING
THE COURSE OF VESSELS." A communication from abroad by Joseph Garcin,
of Marseilles, France, Master Mariner.
Sealed the 16th January 1880, and dated the 19th July 1879.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 19th July 1879.
'
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN SHIPS' LIGHTS AND APPARATUS CONNECTED
THEREWITH FOR SIGNALLING THE COURSE OF VESSELS." [A communication from
abroad by Joseph Garcin, of Marseilles, France, Master Mariner.]
This Invention relates to an improved system of lights for sailing vessels and
stean ships. The lights now in use are only visible through an arc of 90 degrees,
whereas those of this Invention are visible through an arc of 180° at each side of
the vessel (or 360° for both sides), so as to be clearly seen and distinguished from
all points.
The following description of one of the lights will apply equally to the other :-
The light is visible as an ordinary fixed light through an arc of 90° from right
abead to right abeam, and through another arc of 90° from right abeam to right
astern as an intermittent or eclipse light, displayed, say, during 5 seconds, and
giving a flash at the fifth second; at the expiration of 5 seconds the light is entirely
eclipsed for five seconds.
The mechanism for producing the alternate display and eclipse of the light
consists of powerful clock work, capable of running more than 15 hours, and of
working with perfect regularity in any position of the light.
The duration of the eclipse may be increased or diminished if necessary by a
suitable modification of the clock-work. This Invention also consists in an improved
white light to be hung astern at the mizzen masthead, or in any other position
where it will be most visible. For steam ships this light will be displayed and
[Price 6d.1

page_text: eclipsed every 5 seconds by means of clock-work like that above referred to. The
-lanterns themselves-may-be-constructed-of-cylindrical or other form.
In the annexed Drawing I have represented an example of the Invention, and
-will-proceed to describe it with--reference-thereto. Fig. 1 is a starboard elevation
-and-Figure 2 a plan of a steamer provided with the ordinary system of lights now
in use; and Figure 3 shows the arc through-which these lights are visible; Figure 4
shows a plan of the same vessel as Figure 2 but provided with the improved system
of lights of this Invention.
Figure 5 shows the arc through which one of these improved lights is visible.
In Figure 1 the green light is placed at a. The line a, b, indicates the vertical
plane in which both the starboard and port lights are situated. a, b, c, Figure 1,
and d, a, e, Figures 2 and 3, is the angle of 90°, within which the light has only
been visible hitherto, whereas in the improved system of this Invention each light
is visible, but intermittently, through an additional arc of 90°, making 180°
in all.
In Figure 5 f indicates the permanent or fixed light, and g the intermittent or
eclipse light; o is the lamp common to both f and g; c, d, e, is the whole arc of
180°, through which the two kinds of light are visible; e, d, e, d, the two arcs of
90°, within which the permanent and eclipse lights are respectively visible.
With this improved system the lights when placed in their usual positions give
five distinguishing signals:-
-
1st. They show right ahead, or from the direction of arrow 1, Figure 4, as two
permanent lights.
2nd. They show right astern from arrow 2 as two eclipse lights.
3rd. Before the beam or from the direction of arrow 3 one permanent light is
seen.
4th. On the quarter or from the direction of arrow 4 a single eclipse light is
seen.
5th. Abeam or from the direction of arrow 5 cach light shows both as a per-
manent light and as an eclipse light.
The white eclipse light hung in the most visible position astern of a steamer is a
distinctive signal for sailing vessels at river mouths, in straits, and at sea, where
steamers going to windward proceed in the opposite direction to sailing vessels.
The eclipse light will enable the position and course of a steamer to be accurately
discerned, so that collisions may be easily avoided.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alexander Melville Clark in the Great Seal Patent Office on the
17th January 1880.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent.
"IMPROVEMENTS IN SHIPS' LIGHTS AND APPARATUS CONNECTED
THEREWITH FOR SIGNALLING THE COURSE OF VESSELS." A communication from
abroad by Joseph Garcin, of Marseilles, France, Master Mariner.
This Invention relates, 1st, to an improved system of side lights or lanterns for
sailing vessels and steam ships. The usual distinguishing colors are employed, viz.,

page_text: green for starboard and red for port, and no extra expense is incurred for main-
tenance, as one lamp suffices for each light. The side lights now in use are only
visible each through an arc of 90 degrees, whereas those of this Invention are visible
through an arc of 180° at each side of the vessel (or 360° for both sides), so as to
be clearly seen and distinguished from all points.
The following description of one of the lights will apply equally to the other :-
The light is visible as an ordinary fixed or permanent light through an arc of,
say, 90° from right ahead to right abeam, and through another arc of, say, 90° from
right abeam to right astern as an intermittent or eclipse light, displayed, say,
during 5 seconds, and giving a flash at the fifth second; at the expiration of 5
seconds the light is entirely eclipsed for 5 seconde.
The mechanism for producing the alternate display and eclipse of the light over
the arc of 90° abaft the beam consists of powerful clockwork of strong construction,
capable of running more than 15 hours, and of working with perfect regularity in
any position in which the light may be placed.
The Invention also consists in an improved white light, to be hung astern and at
the mizzen mast head, or in any other position where it will be most visible to
serve as a distinguishing light for steam ships. This light will be displayed and
eclipsed every 5 seconds by means of clockwork like that above referred to. The
lanterns themselves may be constructed of cylindrical or other form.
The red and green lights when placed abeam over the side in the usual manner
give 5 distinguishing signals :-(1.) They show right ahead as two fixed or permanent
lights. (2.) They show right astern as two eclipse lights, displayed and eclipsed
every 5 seconds. (3.) Before the beam they show on each side each as a single
fixed light. (4.) Abaft the beam a single eclipse light is shown on each side.
(5.) Right abeam each light shows both as a fixed and an eclipse light.
The white light for steam vessels does not require to be fitted with a graduating
plate like that for the green and red lights before referred to, as in this case the
180° seen of the light are eclipsed every 5 seconds.
The clockwork employed may be of any suitable arrangement, and the lanterns
be made cylindrical or of any other form. The duration of the display and eclipse
of the light may be increased to, say, 10 seconds (more or less) or diminished, and
the act of displaying and eclipsing the light may be rendered sudden, and even
instantaneous.
Having described the nature of the Invention, and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the herein-
before in part recited Letters Patent is,-
1st. A ship's side light or lantern so constructed and operated as to be visible
over a total arc of 180°, viz., as a fixed or permanent light over an are of, say, 90°,
and as an eclipse light over the remainder of the arc, substantially as specified.
2nd. The improved masthead light for steam vessels, as specified.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set my
hand and seal, this Seventeenth day of January, in the year of our Lord One
thousand eight hundred and eighty.
A. M. CLARK. (LS)