IMPROVED MEANS OF CON- CENTRATING LIGHT FOR SIGNALLING PURPOSES, AND IN APPLIANCES CONNECTED
Year: 1872

page_text: LETTERS PATENT to Joseph Ridsdale, of Montpelier House, Tufnell
Park West, in the County of Middlesex, and of the Minories, in
the City of London, for the Invention of "IMPROVED MEANS OF CON-
CENTRATING LIGHT FOR SIGNALLING PURPOSES, AND IN APPLIANCES CONNECTED
Sealed the 22nd November 1872, and dated the 29th May 1872.
PROVISIONAL SPECIFICATION left by the said Joseph Ridsdale at the
Office of the Commissioners of Patents, with his Petition, on the
29th May 1872.
I, JOSEPH RIDSDALE, of Montpelier House, Tufnell Park West,
in the County of Middlesex, and of the Minories, in the City of London.
do hereby declare the nature of the said Invention for "IMPROVED MEANS
OF CONCENTRATING LIGHT FOR SIGNALLING PURPOSES, AND IN APPLIANCES CONNECTED
THEREWITH," to be as follows:-
This Invention relates to means of concentrating the light derived
from lamps or lanterns used for signalling purposes on board ship or
elsewhere, also to appliances for facilitating the concentration of such
light at will.

page_text: "
The Invention consists mainly in the employment of a tube, straight
or tapered, on the "bezil or ring of a bull's eye, the tube being of such
a length as to direct the rays of light to a given spot near to where the
person to whom the signal is directed is stationed, so that if he be at the
helm of a vessel or in any other position, he may know the direction or
"
course the vessel has to be steered, or otherwise recognise the signal
directed to him.
<<
The tube is preferably burred over at the front or formed with a ring
to limit the size of the aperture, which ring may be fixed or moveable
as desired. In some cases I hinge the tube to the "bezil" or to another
ring attached to the lamp or lanthorn, or cause it to slide sidewise or
up or down, as the case may be, and clip it in place by a screw or other
fastener.
The Invention is applicable for all purposes of signalling on board
ship, but it is especially suitable for use for or by the officer in charge of
a vessel to direct the helmsman as to steering the same.
Or to render my Invention applicable to signalling purposes generally,
I may mount the lamp and tube so as to revolve, whereby I am enabled
to direct its light towards any position; or I may cause the tube to
revolve around the lamp by suitably mounting it.
In some cases I attach the coloured glases to a disc which is made to
revolve or to move vertically and gear the dial therewith, so that the
signal sent can be exhibited through an opening in the casing.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Ridsdale in the Great Seal Patent Office 25
on the 29th November 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
RIDSDALE, of Montpelier House, Tufnell Park West, in the County
of Middlesex, and of the Minories, in the City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her 30
Letters Patent, bearing date the Twenty-ninth day of May, in the year

page_text: of our Lord One thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Joseph Ridsdale, Her special licence that
I, the said Joseph Ridsdale, my executors, administrators, and assigns,
or such others as I, the said Joseph Ridsdale, my executors, adminis-
trators, and assigns, should at any time agree with, and no others, from
time to time and at all times thereafter 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 Invention for "IMPROVED MEANS OF CONCENTRATING
LIGHT FOR SIGNALLING PURPOSES, AND IN APPLIANCES CONNECTED THEREWITH,"
upon the condition (amongst others) that I, the said Joseph Ridsdale,
my executors or administrators, 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 Joseph Ridsdale, do hereby declare
the nature of my 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, reference being had to the Drawings here-
unto annexed, that is to say :-
This Invention relates to means of concentrating the light derived
from lamps or lanterns used for signalling purposes on board ship or
elsewhere, also to appliances for facilitating the concentration of such
light at will.
The Invention consists mainly in the employment of a tube, straight
or tapered, on the "bezil" or ring of a bull's eye, the tube being of such
a length as to direct the rays of light to a given spot near to where tho
person to whom the signal is directed is stationed, so that if he be at the
helm of a vessel or in any other position, he may know the direction or
"the vessel has to be steered, or otherwise recognize the signal
directed to him.
"course
The tube is preferably burred over at the front or formed with a ring
to limit the size of the anerture, which ring may be fixed or movable

page_text: "
as desired. In some cases I hinge the tube to the “ ⚫ bezil or to another
ring attached to the lamp or lanthorn, or cause it to slide sidewise or
up or down, as the case may be, and clip it in place by a screw or other
fastener.
The Invention is applicable for all purposes of signalling on board
ship, but it is specially suitable for use for or by the officer in charge of
a vessel to direct the helmsman as to steering the same.
Or to render my Invention applicable to signalling purposes generally,
I may mount the lamp and tube so as to revolve, whereby I am enabled
to direct its light towards any position; or I may cause the tube to 1
revolve around the lamp by suitably mounting it.
In some cases I attach the coloured glasses to a disc which is made to
revolve or to move vertically and gear the dial therewith, so that the
signal sent can be exhibited through an opening in the casing.
The Invention will be more particularly understood by reference to 1
the accompanying Drawings, and by the following detailed description
thereof.
Figure 1 represents in elevation a standard lamp suitable to be fixed
on, say the "bridge" of a vessel, so that the captain or officer in charge
can move the coloured glasses across the face of the bull's eye and 2
indicate to the helmsman to put the rudder over to port or starboard,
or to keep the vessel steady upon her course as desired. The standard A
is formed at its upper part with a socket into which the stem or foot B
of the lamp proper is dropped, and afterwards held in place by a screw
or other pin C taking into an annular groove cut in the stem, so that
the lamp can be turned about the standard as upon a centre for directing
the tube C or the bull's eye D as the case may be into the required
direction for signalling purposes.
The lamp box or shell E carries within it a shield F in which three
glasses G, H, I, are arranged, as clearly indicated in the sectional
elevation and plan views, Figures 2 and 3. One of these glasses is
clear, one green, and the other red, and the shield is in connection
through the frame J with a handle K upon the outside of the lamp box
to enable the handle to be turned by hand to the right or to the left,
the handle being furnished with a spring catch L which is free to drop a

page_text: eye.
66
into a series of notches upon the top edge M to retain the handle and
consequently the colored or the plain glass in place behind the bull's
The top face of the lamp box has a series of glasses N let into it
on which the signals such as "steady," "port," 'starboard," and
"shut off," are shown in words, the words on the several glasses corre-
sponding with the coloured and with the plain glass upon the shield.
The bull's eye is fixed in the nozzle P, and in order to prevent the rays
of light from the bull's eye spreading themselves over a large area, I
hinge a tube C¹ thereto in which all or nearly all the divergent rays are
concentrated within the space formed by the length of the tube, so that
the signal should be seen only by the helmsman or other person to whom
it is directed. The tube is capable of being fixed in position by a thumb
nut R bearing upon or against the fork S of a clip, into which the screw
is free to engage when brought into contact as in Figure 4. The tube'
is thus capable of being thrown back upon its hinge at any time to
expose the bull's eye for cleaning or other causes.
The tube C¹ may be
of any length and may have one or more glasses fitted in its nose or
other part, or even reflectors to concentrate the light to the desired
extent.
In Figure 5 I have shewn a long tapered tube, and this like the
shorter tube shown in Figures 1 and 6 may be arranged so as to screw
on to the nozzle instead of being hinged to it.
Figure 7 represents a tube pinned upon a nozzle of a lamp, so that it
can be swung over as shewn in dotted lines clear of the bull's eye, while
in Figures 8 and 9 the tube is arranged to slide upwards, or it may be
downwards, for that purpose. The tube if fitted with one or more glasses
may be so shaped or shielded, that only a portion of their surfaces shall
be transparent or visible to the sight, and these portions may be of any
shape or design so that narrowed parts thereof starting from, say the
central portion, can by simply turning the cap or the tube in which the
glass is fitted, be directed to the right or to the left for the "port" or
the "starboard" signal, and vertically for the "steady" signal, as
indicated in the views, Figures 10, 11, and 12.
If the glasses last referred to are not fitted in or to the tubes, they
should be upon the shield, which in that case must be upon the outside
of the bull's eye so as to obtain the full effect of the brilliancy derived
from it.

page_text: I have not shown in the Drawing a lamp of this construction, but the
foregoing will enable any practical mechanic to comprehend what is
intended, and also to construct a lamp for the purpose.
Figures 13, 14, and 15 show views of another construction of lamp
for signalling purposes. Here the shield is pivotted to be rotated
vertically by a button or hand hold U, the stem of which works in a slot
in a circular bezel or ring upon the face of the lanthorn to bring the
coloured or the plain glass across the path of the light from the wick V.
The shield or disc has on the back of it a number of pins or studs W,
which engage like the teeth of a crown wheel into other pins or studs X
upon a divided diaphragm Y, so that it moves when the disc, shown
separately in Figures 16 and 17, is moved. The diaphragm, in this
case of skeleton conical form, has a series of glasses fitted to it with the
words "port," starboard," "steady," and "shut off," upon them.
These in their order and according to the direction in which the hand
hold is moved, shows through a pane of plain glass upon the fixed dome
of the lamp. The skeleton conical frame is supported within the dome
by friction rollers Z, Z, clearly shown in Figure 14, but it may be made
to slide in an annular groove if desired. I cover the slot in the bezel by
a band a, and this has upon some portion of it a small spring 6, such as
I have shown in Figures 18 and 19, the free end of which is free to
engage into the notches to retain the disc glasses in position each time
they are shifted over.
In both the constructions of lamps shown I arrange that the smoke
and other products of combustion from the flame shall pass freely away
so as not to smudge the glasses upon the top, and in some cases I employ
a glass chimney to lead the smoke directly into the cap c, the flame
being supplied with oxygen through the apertures d, d, at the bottom or
at the side in the usual manner.
I have in the last described lamp fitted a handle upon the stem of the
tube, a quarter turn of which in one direction releases inclined pinching
faces from contact with the fork, while a quarter turn in the other
direction fixes the tube C¹ in position.
The fitting or fixing of tubes upon the nozzles of signal lamps is an
important feature in my Invention for concentrating the light therefrom,
I therefore in some cases silver or line the tubes with a reflecting

page_text: medium so as to throw back the rays of light given off from the bull's
eye (if a bull's eye is used), and thus to box the light or a greater portion
of it within the tube, so that little or no light or rays of light can be
seen except by the person to whom the tube is directed. Again, in lieu
of silvering or lining the tubes I can fit reflectors within the tube, such
as I have shown in Figures 18, 19, and 20, these being so shaped that
the rays of light from the bull's eye are refracted and boxed within the
tubes.
The faces of the tubes may, as before stated, be partitioned off or
divided so that in lieu of a full circular bulb of light or a strip of light
being seen, a series of smaller bulbs only may be seen, as represented in
Figure 21, and these would appear like so many bright shining stars or
spots upon the face of the tube without any divergent rays, the interior of
the tubes being brilliantly illuminated by single refraction or by double
refraction; if the rays, say of two lights, are caused to cross the paths of
each other, as in the Diagram, Figure 22, the brilliancy visible being
only from the central portion as at e, which may have a pane of plain or
ground glass fitted into it, coloured or uncoloured, or a series of panes of
glass may be arranged upon the disc or upon another disc pivotted upon
or to the casing so that the glasses can be brought in front of or across
the aperture as found convenient.
And having now described the nature of my said Ivention, and in
what manner the same is to be performed, I declare that I claim,-
Firstly. The means herein-before set forth and substantially as shown
in the Drawings for concentrating the light of lamps used for signalling
purposes.
Secondly. I claim the several appliances shown in the Drawings when
arranged for use, in the manner set forth.
Thirdly. I claim the employment of a tube on or to a lamp and in
front of the bull's eye for concentrating the rays of light within the said
tube, such tube being arranged to swing or be moved over, as described.
Fourthly. I claim the construction or formation of lamps and the
arrangement or method of operating discs and visible signals in com-
bination, as described, with reference to Figures 13, 14, and 15, or any
mere modification thereof.

page_text: And, lastly. I claim the concentration of the light from two lamps
within a chamber, the lamps being arranged at an angle to the glass or
aperture from which the "light" can be seen, as set forth.
In witness whereof, I, the said Joseph Ridsdale, have hereunto set
my hand and seal, this Twenty-sixth day of November, One
thousand eight hundred and seventy-two.
JOSEPH RIDSDALE. (L.S.)