A Means of Increasing the Efficiency of Lighthouse Lights.
Year: 1894

page_text: Date of Application, 18th Oct., 1894
Complete Specification Left, 24th July, 1895-Accepted, 12th Oct., 1895
PROVISIONAL SPECIFICATION.
A Means of Increasing the Efficiency of Lighthouse Lights.
I, JOHN RICHARDSON WIGHAM, of 33 Capel Street, Dublin, Lighthouse
Engineer do hereby declare the nature of this invention to be as follows:-
In what are termed fixed lights for lighthouses the light in clear weather is
continuously visible to the mariner and for guiding his ship, taking bearings &c.
his attention need never be drawn from the light, and for these reasons fixed lights
are of great importance to navigation, but as the illumination from such fixed
lights is diffused all over the horizon the light is necessarily much less powerful
than when the rays of light are condensed into beams by lenses or reflectors, which
beams, of necessity must be rotated so as to send their great light consecutively to
every part of the horizon, of course, having intervals of darkness between the
beams, which are frequently a source of embarrassment to the mariner. My
present invention consists in a method of applying lenses in lighthouses, beacons
and other places where strong lights are required in such a manner and with such
apparatus that the superior light which these lenses transmit. may be available to
the mariner and at the same time the light may be continuously under his
observation; in brief, to give the mariner all the advantage of a fixed light with
the greater power and the characteristic effect of a revolving light. I effect this
purpose by causing the lenses to revolve at such a rate of rotation that the
impression of the flash from one lens will not have left the eye of the observer till
that from the succeeding lens reaches him. The method I employ for this rapid
rotation of the lenses is to fix them over a vertical spindle with a case hardened
point working in a case hardened socket and the point surrounded by oil for the
purpose of lessening the friction if necessary or in some cases where the weight of
the lenses is very great a chamber of mercury is used for the purpose of diminishing
the friction. The motion is communicated to the revolving apparatus either by the
ordinary clockwork employed in lighthouses or by a petroleum engine or gas engine
of ordinary construction as may be found most convenient. When gas is the
illuminant I combine with this arrangement a method by which the gas light is
intermitted so rapidly as to present its light continuously to the observer without
sensible intervals of darkness while at the same time the consumption is diminished
in proportion to the time during which the illuminant is not consumed. I effect
this intermission by valves by which the gas is admitted to the burners for each lens
or reflector and shut off therefrom at the required intervals by means of a cam
connected with the machinery by which the lenses or reflectors are rotated-the
cam lifts a straight rod attached to the valve and in so doing opens it for the
passage of the gas, and as it revolves closes the valve by the lowering of the rod,
thus shutting off the supply of gas, a small byepass, maintaining a very small,
almost invisible light, being fixed to the burner in the focus of each lens or
reflector so as to provide for its instantaneous re-ignition when the valve is again
opened by the revolution of the cam. In the case of biform, triform or quadriform
lights where 2, 3, or 4 vertically superposed lenses are used, this rod actuated as
bove described by the cam, extends to all the burners and opens and closes all the
valves simultaneously so that the flashes from the 2, 3 or 4 lenses form one
unbroken beam (just as if they were emitted from one lens only) as at Gulley
Head, Mew Island and Tory Island lighthouses. The valve is cylindric in form
divided in the centre by a diaphragm, on the under side of which is the entrance

page_text: for the gas and on the upper side is the exit. In the diaphragm is formed a taper
opening which receives a dise of the same taper both being ground in so as to be
gas tight, and this disc is raised and lowered by means of the rod and cam herein-
before described, the rod passing through a stuffing box at the top and bottom of
the cylinder, or I effect the intermission by simply rotating by means of a belt or
cog wheel, the barrel of a ground in gas cock having in the said barrel the
necessary number of slots for the emission of gas and solid spaces for its retention.
Another part of this invention consists in the application of this method of using
lenses to existing lights so that they may be capable of giving the power of their
revolving light and yet be visible continuously without sensible intervals of
darkness. This invention is applicable not only to lights constructed on the
ordinary plan but also to the lights known as biform, triform quadriform &c. or
those described in Letters Patent granted to me from time to time Nos. 2247/1891
4573/1891 14,990/1889 15,822/1885 14,686/1884 14,685/1884 6195/1882 790/1882
1160/1879 1743/1876 1015/1872 3771/1869 945/1865:
Dated this 31st day of October 1894.
JOHN RICHARDSON WIGHAM.
A Means of Increasing the Efficiency of Lighthouse Lights.
1, JOHN RICHARDSON WIGHAM of 33 Capel Street Dublin, Lighthouse
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:-
In what are termed fixed lights for lighthouses the light in clear weather is
continuously visible to the mariner and for guiding his ship taking bearings &c.,
bis attention need never be drawn from the light, and for these reasons fixed lights
are of great importance to navigation, but as the illumination from such fixed lights
is diffused all over the horizon the light is necessarily much less powerful than
when the rays of light are condensed into beams by lenses or reflectors which
beams of necessity must be rotated so as to send their great light consecutively to
every part of the horizon, of course, having intervals of darkness between the
beams which are frequently a source of embarrassment to the mariner. My
present invention consists in a method of applying lenses in lighthouses beacons and
other places where strong lights are required, in such a manner and with such
apparatus that the superior light which these lenses transmit may be available to
the mariner; and at the same time the light may be continuously under his
observation; in brief to give the mariner all the advantage of a fixed light with
the greater power and the characteristic effect of a revolving light.
I effect this purpose by causing the lenses to revolve at such a rate of rotation
that the impression of the flash from one lens will not have left the eye of the
observer till that from the succeeding lens reaches him. The method I employ for
this rapid rotation of the lenses is to fix them over a vertical spindle with a case
hardened point working in a case-hardened socket and the point surrounded by oil
for the purpose of lessening the friction if necessary, or in some cases where he
weight of the lenses is very great a chamber of mercury is used for the purpose of
diminishing the friction. The motion is communicated to the revolving apparatus
either by the ordinary clockwork employed in lighthouses or by a petroleum engine
or gas engine of ordinary construction as may be found most convenient.
gas is the illuminant I combine with this arrangement a method by which the gas
light is intermitted so rapidly as to present its light continuously to the observer
without sensible intervals of darkness while at the same time the consumption is
diminished in proportion to the time during which the illuminant is not consumed.
When

page_text: Ifect this intermission by valves by which the gas is admitted to the burners for
each lens or reflector and shut off therefrom at the required intervals by means of a
cam C connected with the machinery by which the lenses or reflectors are rotated-
the cam C lifts a straight rod G attached to the valve and in so doing opens it for
the passage of the gas and as it revolves, closes the valve V by the lowering of the
rod, thus shutting off the supply of gas, a small bye pass maintaining a very small,
almost invisible light, being fixed to the burner in the focus of each lens or reflector
so as to provide for its instantaneous re-ignition when the valve is again opened by
the revolution of the cam. In the case of biform, triform or quadriform lights
where 2, 3 or 4 vertically superposed lenses are used, this rod, actuated as above
described by the cain, extends to all the burners and opens and closes all the valves
simultaneously so that the flashes from the 2, 3, or 4 lenses form one unbroken
beam (just as if they were emitted from one lens only) as at Galley Hoad, Mew
Island and Tory Island lighthouses. The valve chamber E is cylindric in form
divided in the centre by a diaphragm, ou the under side of which is the entrance
for the gas and on the upper side is the exit. In the diaphragm is formed a taper
opening which receives a disc V, of the same taper both being ground in so as to
be gas tight, and this disc is raised and lowered by means of the rod G and cam
iereinbefore described, the rod passing through a stuffing box D at the top and
bottom of the cylinder, or effect the intermission by simply rotating by means of
belt or cog wheel the barrel of a ground in gas cock Fig. 2 having in the said
barrel the necessary number of slots for the emission of gas and solid spaces for its
retention.
Another part of this invention consists in the application of this method of using
lenses to existing lights so that they may be capable of giving the power of their
revolving light and yet be visible continuously without sensible intervals of
darkness. This invention is applicable not only to lights constructed on the
ordinary plan but also to the lights known as biform, triform quadriform &c., or
those described in Letters Patent granted to me from time to time Nos. 2247/1891
4573,1891 14,990/1889 15,822/1885 14,686/1884 14,685/1884 6195/1882 790/1882
1160/1879 1743/1876 1015/1872 3771/1869 945/1865.
In the accompanying drawings Figure 1 represents the method of rotating the
lenses round the burners, A, when gas is used as the illuminant the gas being brought
into the focus over the lens and B, when the gas is brought into the focus under the
lenses or when oil or the electric light is used as the illuminant; Figure 2 represents
the ground in gas cock and pulleys, one half being in section.
Figure 3 represents the general valve arrangements-
E. Valve chamber.
S. The main gas supply pipe.
I. The inlet pipe to valve.
O. The outlet pipe to burner.
G. The rod for lifting valve.
D. Stuffing boxes.
A. Catch for putting burner in & out of gear.
R&C. Roller & cam.
B. Burner.
F. Flue for burner.
Figure 1. represents valve arrangement in section.
D. Stuffing box,
O. Outlet pipe to burner.
V. Valve.
K. Valve seat.
L. Valve lifting rod.
H. Connecting collars.
M. Connecting rod.
A. Catch for putting burner in & out of gear.
G. Litting rod.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
-claim is
rate of
1. The method of rotating lenses hereinbefore described at such a
rotation that the impression of the flash from one lens will not have left the eye of
the observer till that from the succeeding lens reaches him, and thus the light is
rendered continuous, never leaving the eye, while presenting a characteristic
fluctuating appearance.
2. The intermission of gas flames at a similar rate so that the light shall be
continuously in the eye while presenting in like manner a pulsating appearance
owing to the rapid extinctions, and re-ignitions of the gas while the consumption is
reduced practically by one half.
Dated this 17th day of July 1895.
JOHN RICHARDSON WIGHAM.