IMPROVEMENTS IN FOG AND OTHER SIGNALS
Year: 1875

page_text: °
LETTERS PATENT to John Richardson Wigham, residing at Capel
'Street, in the City of Dublin, Gas Engineer, for the Invention of
“IMPROVEMENTS IN FOG AND OTHER SIGNALS."
PROVISIONAL SPECIFICATION left by the said John Richardson
Wigham at the Office of the Commissioners of Patents, with his
Petition, on the 30th January 1875.
I, JOHN RICHARDSON WIGHAM, residing at Capel Street, in the City
of Dublin, Gas Engineer, do hereby, declare the nature of the said.
Invention for "IMPROVEMENTS IN FOG AND OTHER SIGNALS," to be as
follows:-
My Invention relates to the production of audible signals by means-
"siren."
of an apparatus known as a
Such apparatus as heretofore
employed consists of a rapidly revolving disc having apertures therein,
against which a jet of air is directed, so that a sound is produced by the
action of the apertures and the surfaces of the disc between them.
0

page_text: alternately, allowing, the passage of the air jet and intercepting the
same..
According to my present Invention I employ a combination of two
or more such revolving discs for producing sounds suitable for sig-
nalling, which discs may be provided with an unlike number of slots or
apertures so as to produce sounds of more than one note, or I employ
only one such disc with apertures or radial slots of different sizes, and
so arranged as to produce a more penetrating sound than heretofore.
For actuating such apparatus I. employ either steam, air, or carbonic
acid gas, or I employ electricity, and I so arrange the apparatus that by
the action of the steam or air that drives the siren and produces the
sound, the faces of the disc are made at the same time to rotate and turn
to every part of the horizon, and so that the shutting off or turning
on of the steam or other actuating agent is effected in a perfectly
automatic manner without the intervention of complicated machinery.
.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Richardson Wigham in the Great Scal
Patent Office on the 30th July 1875.
"TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
RICHARDSON WIGHAM, residing at Capel Street, in the City of Dublin,
Gas Engineer, send greeting.
1
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of January, in the year
of our Lord One thousand eight hundred and seventy-five, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Richardson Wigham, Her
special license that I, the said John Richardson Wigham, my exe-
cutors, administrators, and assigns, or such others as I, the said John
Richardson Wigham, my executors, administrators, 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

page_text: Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN FOG AND OTHER SIGNALS," upon the condi-
tion (amongst others) that I, the said John Richardson Wigham, my
executors or administrators, by an instrument in writing under my, or
their, or one of their hands and scals, 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
Scal Patent Office within six calendar months next and immediately..
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Richardson Wigham, do
hereby declare the nature of the 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
accompanying Sheet of Drawings and to the figures and letters marked
thereon, that is to say :-
My Invention relates to the production of audible signals by means
of an apparatus known as a "siren." Such apparatus as heretofore
employed consists of a rapidly revolving disc having apertures therein,
against which a jet of air is directed, so that a sound is produced by the
action of the apertures and the surfaces of the disc between them
alternately allowing the passage of the air jet and intercepting the
same.
According to my present Invention I employ a combination of two
or more such revolving discs for producing sounds suitable for sig.
nalling, which discs may be provided with an unlike number of slots or
apertures so as to produce sounds of more than one note, or I employ
only one such disc with apertures or radial slots of different sizes and
so arranged as to produce a more penetrating sound than heretofore.
-
For actuating such apparatus I employ either steam, air, or carbonic
acid gas, or I employ electricity, and I so arrange the apparatus that by
the action of the steam or air that drives the siren and produces the
sound, the faces of the disc may be made at the same time to rotate
and turn to every part of the horizon, and so that the shutting off or
turning on of the steam or other actuating agent is effected in a per-
fectly automatic manner without the intervention of complicated
machinery; or I fix one or more of the revolving dises with bevilled

page_text: required, the discs being operated upon cither simultaneously or con-
secutively.
DESCRIPTION OF THE DRAWINGS.
The accompanying Drawing shews an elevation of my before described
improved signalling apparatus. A, A¹, are cylinders containing the
revolving discs with slots for producing sound, a horn B being fixed to
the one cylinder A¹ so as to project the sound in a certain direction. The
discs are fixed on the spindle C, to which a rapid rotary motion is
imparted by means of the pulley D from any suitable motor; E, E, are
pipes conducting the steam, air, or other fluid, under pressure into the
cylinders A, A', for producing the sound by impinging. upon the rotating
discs. These pipes have cocks F, F¹, the spindles of which are provided
with toothed pinions G, G¹, in gear with a toothed ring H which is
caused to revolve so as, by turning the cocks, to cut off and admit the
steam alternately to the cylinders and thus produce intermittent sounds.
The ring H is carried by brackets I fixed to a disc J which rests on
rollers K, and is caused to rotate by any convenient motor, or by the
samo power which actuates the discs of the siren. If desired the table
carrying the cylinders A, A', and horn B may also be made to rotate on
a vertical axis, so as to move the siren into different positions relative to
'the horizon as before described.
Having thus described the nature of my Invention and in what
manner the same is to be performed, I claim,—
First. The use for fog or other signals of a combination of two or
more slotted revolving discs upon which jets of steam, air, or other
fluid are made to impinge so as to produce sound, substantially as hercin
described.
Second. The use, for the purpose above mentioned,, of a single
revolving disc having radial slots of different sizes so as to produce
varying sounds, substantially as herein described.
Third. Arranging signalling apparatus such as is above referred to, so
that the discs while they are rotated are at the same time turned into

page_text: varying positions, the shutting off and turning on of the steam or other
fluid for producing intermittent sounds being effected automatically,
substantially as herein described.
In witness whereof, I, the said John Richardson Wigham, have
hereunto set my hand and seal, this Twenty-fourth day of July,
of our Lord One thousand eight hundred and seventy
in the
five.
year
JOHN RICHARDSON WIGHAM. (L.S.)