IMPROVEMENTS IN THE USE AND APPLICATION OF ARTIFICIAL LIGHT
Year: 1859

page_text: LETTERS PATENT to Samuel Thomas Cooper, of Upper Clapton, Gentle-
man, for the Invention of "IMPROVEMENTS IN THE USE AND APPLICATION OF
ARTIFICIAL LIGHT."
Sealed the 31st August 1859, in pursuance of an Order of the Lord Chancellor,
PROVISIONAL SPECIFICATION left by the said Samuel Thomas Cooper at
the Office of the Commissioners of Patents, with his Petition, on the
17th February 1859.
I, SAMUEL THOMAS COOPER, of Upper Clapton, Gentleman, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN THE USE & APPLICATION
OF ARTIFICIAL LIGHT," to be as follows:-
This Invention consists in the use & application of coal gas or any other
kind of illuminating gas for signals & other purposes, by igniting & extinguish-
ing it in a way which has not hitherto been practised, & is especially applicable
to signals for railways, lighthouses, & ships at sea.
For this same Invention, Provisional Protection under the same title
(Certificate No. 140) was allowed to me on my Petition & Provisional
Specification, recorded in the Office of the Commissioners of Patents for
Inventions on the 17th day of January last; but inasmuch as in the said
Provisional Specification 1 inadvertently omitted some details of arrangement

page_text: & adaptation, under the impression that I might reserve the description of
them for the Final Specification, & finding now that the description of these
details is essential in order that my Provisional Specification may state
distinctly & intelligibly the whole nature of the Invention, & explain the
means by which the improvements are to be carried into effect, in order that
my claims may not be jeopardized by such omission, instead of making
application to be allowed to amend & alter the said Provisional Specification
recorded on the 17th January last, I have this day left at the Patent Office a
Declaration & Petition for the same Invention, of which I do hereby declare
this to be the correct Provisional Specification, & intended to replace the
former one.
The essential condition of this Invention is, the instantaneous ignition of jets
of gas as they issue from a burner, by one or some of them impinging upon &
coming in contact with a fixed flame (which may be that of gas or of an oil
or other lamp), kept continuously burning. in combination with an arrange-
ment whereby the gas is supplied from the main through a branch pipe, &
turned on to or cut off from the burner by the action of an ordinary shut-off.
cock placed at a distance from it. The branch pipe is connected with the
main from a gasometer, & fitted at one end (next to the main) with a shut-off
cock, & at the other (close to the burner) with a spring valve, which acts at a
lower pressure than that of the gas in the main. The effect of this arrange-
ment is, that when the shut-off cock is opened, the gas from the main passes
through the branch pipe at a pressure which opens the spring valve & causes the
jets to issue from the burner, & when the shut-off cock is closed, the pressure
in the branch pipe is reduced until the spring valve closes, cutting off the
supply to the burner, but still keeping the branch pipe full of gas, & excluding
atmospheric air. The result of these combinations is, that when the gas is
turned on from the main, the jets issue from the burner & are at once ignited,
& when it is turned off they are extinguished, & this double action is effected
merely by opening or closing the shut-off cock, which may be placed at any
distance required in practice from the burner which it supplies with gas.
As a means of carrying out the Invention, I propose to lay down two pipes
for the conveyance of the gas to be used, one of a small diameter to supply
the gas for the fixed flame, the other of a diameter sufficiently large to supply
the gas to the burners which are to be used for illuminating purposes; or the
smaller pipe (or an oil or other lamp may be used to produce the fixed flame)
may be a branch from the larger one. In the practical application of this
Invention when in use, the gas from the smaller pipe or other fixed flame will
be kept constantly lighted. The supply of gas in the other pipe will be

page_text: regulated & may be turned on or off by means of a cock or valve at some
given distance from the burner or burners which such pipe is intended to
supply with gas. By this arrangement, as before explained, the moment the
gas issues from the larger pipe, the jet or jets of gas from it coming in contact
with the fixed flame will be ignited, & communicate their flame to the jets
from other burners supplied with gas from the larger pipe, if these are so placed
in contiguity with each other as to be calculated to produce that result.. Thus,
by simply turning on the gas to the burners of the larger pipe, a body of gas
flames of any required dimensions or intensity will be instantaneously produced,
& kept burning as long as the gas from the larger pipe is turned on, & the
same will be immediately extinguished by turning off the gas in the larger
pipe, & the operations of alternately lighting up and extinguishing these flames
may be repeated at will by simply opening or closing the valve which
regulates the supply of gas to the larger pipe.
The arrangement for the practical application of my Invention just
described is to be adapted for signals on railways in the following manner :-
A lantern containing the burners of the small gas pipe or any other fixed
flame & of the large gas pipe is to be placed at any elevation or position so as
to be clearly visible, & may be fixed at any distance that may be desired from
a railway station or other point from which the signal is intended to be
worked. The valve of the larger pipe by which the gas is to be turned on' er
off is to be at or close to such station or working point, & provided with a
handle, by means of which the person in charge of the signal is to turn the
gas on or off as required. By this mode of signalling, a bright body of light,.
which for distinction I call a beacon, can be displayed in a moment at dis-
tances from the station far greater than any kind of signal now in use, & with
such brilliancy & certainty of effect, that it cannot fail to be plainly visible, &
will be most effective for night or fog signals.
In cases where gas is produced on board of ships, gas light signals on the
plan above described can be displayed at the mast head, or any other elevated,
part of the ship's masts, or on the chimney funnel or paddle boxes of a
steamer. The gas pipes in these cases would be carried up the mast, or
funnel, or paddle box, & the lantern containing the burners would be fixed at
the point where the signal is intended to be displayed, whilst the regulating
valve would be at some convenient place of access on deck or elsewhere.
For lighthouses this Invention can be applied in a very useful way to pro-
duce the effect of revolving lights, regulating the time of the appearance or
occultation of the light with the greatest precision, & simplicity. The
burners of a small & of a large gas pipe being, arranged in the manner above

page_text: described for a railway signal in order to produce the illuminating effect
required for a lighthouse, there may be a series of lanterns, each supplied with
its permanently ignited jet of gas or other flame, & a set of large burners. to
be lighted up. By means of clockwork or some other mechanical contrivance,
the valve of the large pipe, which regulates the supply of gas to the signal
burner, may be opened or closed at any required intervals of time, & the light
will be visible during the time the gas is burning, & invisible being extin-
guished during the time the gas is turned off.
This Invention may also be used to establish signals along a line of railway
for the purpose of denoting to a travelling train the interval of time since the
passage of the last preceding train. In carrying this application of the
Invention into effect, a gas pipe is to be laid down along the line from station
to station, & the signals are to be placed at points two to three miles apart.
At each of these points there will be a lantern with its fixed flame, & signal
burner attached to a branch pipe provided with a spring valve, as herein-before
described. The gas will be supplied to the signal burner from a small
gasometer containing a small supply of gas, say, for two minutes' consumption.
To this gasometer will be fitted an apparatus for turning the gas on to the
burner, & at the same time filling the gasometer from the main by the action
of the train (on the handle of a supply valve) in passing over the rail. As the
train passes each signal lantern, the beacon flame will be lighted up, & continue
burning two minutes if that be the regulated supply, indicating to any following
train which comes up whilst the beacon is alight, that another train is only
two minutes or less in advance. The passing train is thus warned in time to
reduce it's speed, a notice which on a foggy night may often save a slow
train from being run into by an express train.
The mode of lighting up jets from gas burners as the gas issues from them
with the flame of a small jet kept constantly burning, may be applied to any
kind of gas burners for any illuminating purposes, such as street lamps,
theatres, & public or private buildings & shops, in all of which cases a
great number of gas jets may be ignited or extinguished simultaneously by
turning the gas on or off.
I will not here enter into further details of the purposes to which the im-
provement of regulating a light from a gas burner by the action of a shut-off
cock at a great distance from the former may be applied, but it is obvious that
the Invention may be used with great effect to prevent. accidents on railways
by adapting it for station signals, distant signals, or train signals under proper
arrangements suited to the requirements in each case.
The effects above described of alternately displaying or withdrawing the

page_text: light of ignited jets of gas may be produced in another way, viz., by using
only one pipe to convey the gas, and at one time turning the gas fully on & at
another turning it nearly off, so as to reduce it to a small light, not visible at
a distance. This is to be effected by fitting to the pipe a regulating valve or
cock, which is to be so constructed that when fully opened the gas will be
supplied to the burners to the full extent of the jets to be lighted up, but
which is to be furnished with a stop, reducing the supply of gas when nearly
turned off to a minimum quantity, just to keep a small flame burning ready to
light up the jets when fully turned on. I do not describe any particular mode
of constructing this valve, any further than to say, that the stop above
referred to is to be so arranged as to prevent the gas from being entirely
shut off & extinguished when in use for the purposes of this Invention.
I have in the 'foregoing Specification pointed out various modes in which my
Invention can be applied, & I have described various means of carrying it
into effect, but I only intend to claim as of my Invention those improvements
which are new, & have not hitherto been in use.
SPECIFICATION filed in pursuance of the conditions of the Letters Patent
and of an Order of the Lord Chanceller, by the said Samuel Thomas
Cooper in the Great Seal Patent Office on the 31st August 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SAMUEL
THOMAS COOPER, of Upper Clapton, in the County of Middlesex, Gentleman,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventeenth day of February, in the year of our
Lord One thousand eight hundred and fifty-nine, in the twenty-second year
of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me; the said Samuel Thomas Cooper, Her special licence that I, the
said Samuel Thomas Cooper, my executors, administrators, and assigns,
or such others as I, the said Samuel Thomas Cooper, my executors, admini-
strators, and assigns, should at any time agree with, and no others, from
time to time and at all tinies 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 "IMPROVEMENTS IN THE USE AND APPLICATION OF
ARTIFICIAL LIGHT," upon the condition (amongst others) that I, the said
Samuel Thomas Cooper, my executors or administrators, by an instrument
:

page_text: in writing under my, or their, or one of their hands and seals, should par-
ticularly 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 Samuel Thomas Cooper, 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:-.
.
This Invention consists in the use and application of coal gas or any other
kind of illuminating gas for signals and other purposes, by igniting and
extinguishing a jet or jets of such gases on a plan or in a manner which has
not hitherto been practised for such purposes, and is especially applicable to
signals for railways, lighthouses, and ships at sea.
For the practical application of my said Invention, the mode of carrying it
into execution is to effect the instantaneous ignition of a jet or jets of gas as
they issue from a burner, by causing one or some of them to impinge upon
and come in contact with a fixed flame (which may be that of gas or of an oil
or other lamp) kept continuously burning in combination with an arrange-
ment, whereby the gas intended to produce the jets as or for signals is supplied
from the gas main pipe through a branch pipe, and turned on to or cut off
from the burner by the action of an ordinary shut-off cock placed at any
required distance from the point where the light is intended to be exhibited.
This branch pipe is connected with the main from a gasometer, and fitted at
one end (that next to the main) with a shut-off cock, and at the other end
'(close to the burner) with a spring valve, which acts at a lower pressure than
that of the gas in the main. The effect of this arrangement is, that when the
'shut-off cock is opened the gas from the main passes through the branch pipe
at a pressure, which opens the spring valve and issues in a jet or jets from the
'burner; and when the shut-off cock is closed, the pressure in the branch pipe
is reduced until the spring valve closes, cutting off the supply of gas to the
'burner; but still keeping the branch pipe full of gas and excluding atmospheric
air. The result of this arrangement is, that when the gas is turned on from
the main the jets issuing from the burner are at once ignited, and when it is
'turned off they are extinguished, and this two-fold action is effected merely by
opening or closing the shut-off cock, which, as before stated, may be placed at
any distance required in practice from the burner of which it regulates the
supply of gas.
-
As a means of carrying out the Invention when gas is employed for.the

page_text: fixed flame, I propose to lay down two pipes for the conveyance of the gas to
be used, one of a small diameter to supply the gas for the fixed flame, the
other of a diameter sufficiently large to supply the gas to be used for signals
or other illuminating purposes; or the smaller pipe may be a branch from the
larger one, or an oil or other lamp may be used to produce the fixed flame, in
which last-mentioned case the smaller gas pipe and its burner would not be
required. By this arrangement the gas may be turned on or off at pleasure,
and the jet or jets being so placed in contiguity with the fixed flame and with
each other as to be calculated to produce the required result, any number of
gas flames of any required illuminating power may be instantaneously pro-
duced and kept burning as long as the gas is turned on, and will be
immediately extinguished by turning off the gas, and the operations of
alternately lighting up or extinguishing these flames may be repeated at will
by simply opening or closing the valve which regulates the supply of gas to
the signal or illuminating burners.
My said. Invention may be adapted for railway signals in the following
manner A lantern containing the burners of the fixed flame and of the
signal jets (which, for distinction, I call the beacon light,) is to be placed at
any elevation or position to render it clearly visible from any required point or
points, and may be fixed at any distance that may be desired from a railway
station or other point from which the signal is intended to be worked. The
shut-off cock or valve by which the gas is to be turned on or off is to be at or
close to such station or working point and provided with a handle, by means
of which the person in charge of the signal is to turn the gas on or off as
required. By this mode of signalling, body of light can be displayed in a
moment at distances from the station far greater than by any kind of signal
now in use, and with such brilliancy and certainty of effect that it cannot fail
to be plainly visible at any point required, and will be most effective for night
or fog signals..
.
a
In cases where gas is produced on board of ships, gas light signals on the
plan above described can be displayed at the mast-head or any other elevated
part of the ship's masts, or on the chimney funnel or paddle boxes of a
steamer. The gas. pipes in these cases would be carried up the mast or
funnel or paddle box, and the lantern containing the burners would be fixed
at the point where the signal is intended to be displayed, whilst the regulating
valve would be at some convenient place of access on the deck. or at any other
part of the ship.
For lighthouses this Invention can be applied in a very useful way to

page_text: produce the effect of revolving lights, regulating the time of the appearance or
.occultation of the light with the greatest precision and simplicity. The
burners of a small and of a large gas pipe being arranged in the manner
above described for a railway signal, in order to produce the illuminating
effect required for a lighthouse, there may be a series of lanterns, each
supplied with its permanently ignited jet of gas or other flame, and a set
of signal or illuminating burners. By means of clockwork or some other
.mechanical contrivance, the valve which regulates the supply of gas to these
burners may be opened or closed at any required intervals of time, and the
light will be visible during the time the gas is burning, and invisible (being
.extinguished) during the time the gas turned off.
This method of applying the Invention will admit of many variations as to
time, in the appearance, and duration of the light, and in point of precision,
effect, and economy, will be superior to any system of revolving lights now
in use.
The lighting up and extinguishing gas jets at a distance as they issue from
the burners by contact with a small fixed flame on the plan of this Invention
may be also made available for other illuminating uses, such as lighting streets,
factories, theatres, and public buildings or shops, where a great number of gas
lights being used, it will be convenient and economical to light them up or
extinguish them simultaneously in a moment by turning the gas on or off;
the use of the pressure valve, as before described, rendering the alternate action
secure and certain, whatever may be the variation of pressure in the main.
'
Signals on various plans are in use on different railways, but not one of
them combines the requisites of a really effective night signal. That which
is considered the best is a lamp with a fixed light in the centre, and glass
sides of different colors, shifting by the action of a wire, worked round a
cylinder, so as to show when put into operation a white, or red, or other
colored light, alternately, according to the position and color of the glass.
As a distant signal, this lamp is placed at an elevation of thirty to forty feet,
and on a fine night is visible at a great distance to an approaching train, and
also at the station it is attached to, but in a fog or hazy weather it becomes.
almost useless, and even with a clear atmosphere it requires a steady look out
to be seen by: the driver at a sufficient distance to slacken speed or stop in
time; but even this. essential condition of safety, with his vision impaired or
obstructed by the glare of the furnace or the forward drift of waste steam, he
often finds it a difficult task to accomplish in the finest weather. The evidence
taken in the enquiries into numerous cases of accident incontestably proves

page_text: that the present system of night signals leaves much to be desired, and that
on occasions when they are most wanted they really afford no protection
whatever.
The great value of a signal for railway purposes on the plan of my Invention
is, that it can be displayed so far from the station that instead of requiring a
look out to be seen at a distance, it adınits of the train being close upon it before
it be necessary to stop or slacken speed. This, in foggy weather, when a signal
cannot be seen at a distance, would be a great guarantee against accident.
To render the description of my Invention more clear and intelligible, I
refer to the annexed Diagrams. In plan No. 1, A is a gas main, to be carried
alongside a railway, or to any point where the Invention is intended to be
used, and any length required for the supply of branches for signal burners, of
which any number, whether for railway or other signals, may be attached to
the main from distance to distance; B is the valve or shut-off cock, regulating
the supply of gas from the main; C is the branch pipe, supplying gas to the
sigual burner. D is a spring valve at the end of the branch pipe close to
the signal burners. When, by opening the valve B, the gas is turned on from
the main, the additional pressure in the branch pipe C opens the spring valve
D, and the jets issue from the signal burner. The valve B being closed, the
pressure from the main ccases, and the valve D closes, thereby extinguishing
the signal lights, and at the same time preventing the escape of gas, and
excluding air from the branch pipe. E is a box containing the spring valve D;
F is a small jet of gas kept continuously burning. The flame of an oil or any
other lamp constantly lighted may be used for the same purpose. G is a pipe
supplying gas either from the main or the branch pipe to the flame F;
H, H, are signal burners with the gas turned off; I, I, signal burners with
the gas ignited, being turned on.
In plan No. 2, the distant signal No. 1 shews a red light produced by the
fixed flame, and a beacon or signal light. It may be at so great a distance
from the station, that in approaching the station a look out far ahead will
not be required; placed at a moderate elevation and throwing its rays upon'
the rails, it will be plainly visible to the driver, not only at a distance as the
train approaches the signal, but especially when close upon and passing by it,
and he then will have ample time to reduce speed or stop, if required, before
he is close on the station. The red light when alone visible might in some
cases be used as a danger signal, and the beacon light as a safety signal, in
other cases it may be advisable to use the white light to denote danger. The
cocks b and c at the station supply or shut off the gas from the main to the
branch and supply pipes d, e, f, g, and regulate its pressure at the signal

page_text: lanterns. A minute or two before a train is due, the station being clear, the
cock bis opened, and the gas turned on to the supply pipes & and e, when
the beacon is immediately lighted up; this is an unmistakeable signal to go
on to the station. In passing signal No. 2, the train, acting upon a valve at h,
opens that valve, when the gas being turned on, a beacon light is immediately
displayed, indicating to the station that the train has passed the distant signal,
and is approaching. This light will be very conspicuous, and instantly visible
at the station; it is supplied with gas through a small gasholder, which is
filled from the branch (d) by the opening of the valve h with a quantity of gas
to burn two or three minutes. The moment the signalman at the station sees
the light of this train beacon, he shuts the cock and opens the cock c. By
the former action the distant beacon No. 1 is extinguished, and the red light
alone being visible, any approaching train is warned to stop till the station is
clear, and the distant beacon light again shown. By opening the cock c, the
station beacon No. 3 is lighted up, and remains till the train bas left the
station, when it is shut off. Beacon No. 3 serves two purposes, it lights up
the station brilliantly whilst the train is there, and is a signal not to enter the
station to any train which by inadvertence might have passed the distant
signal before the station was clear. The station beacon should be so brilliant
and conspicuous as to form an effectual danger signal to an approaching train.
For the purpose of signals along the line to denote to travelling trains the
interval of time since the passage of the last preceding train, a gas pipe is to
be laid along the line from station to station.
The signals are to be placed at points, say, two miles apart, and at each of
these points there will be a lantern, with its fixed flame and beacon burner,
and a small gasholder containing a supply of gas only for a few minutes
consumption. To this gasholder will be fitted an apparatus for turning the
gas on to the beacon burner by the action of the train on a cam and a supply
valve in passing over the rail. As the train passes each of these signal
lanterns, the beacon will be lighted up, and continue burning two or three
minutes (if that be the regulated time), indicating to any following train which
comes up whilst the beacon is alight that another train is only two or three
minutes or less ahead. The driver of the former train is thus warned in time
to reduce speed, a notice which on a hazy or foggy night may often save a
slow train from being run into by an express train.
The following are some of the advantages of my said Invention:―
. 1. The signal can be displayed at points any required distance, from a few
yards to several miles, from the station or place from which it is worked.
Hence, when used as a distant signal, it can be displayed so far from the

page_text: station, that at the moment when it is his duty to reduce the speed of the
train or stop, the driver will be close to the signal, and have it in full view,
instead of having to strain his sight to see it a long way off.
2. The signal is displayed at these distant points the moment the gas is
turned on at the station, and it can, if required, be repeated simultaneously at
many points to the next station both ways.
8. The decisive character of the signal leaves no room for doubt, its
brilliant appearance or total absence being clear and intelligible signs which
cannot be misunderstood.
4. The apparatus and mechanical means employed are easy of construction,
and when established, will be so little liable to derangement or deterioration,
that they will last for years at a trifling expense of maintenance.
5. The management of the apparatus and the working of the signals are simple,
easy, and economical, requiring no extraordinary skill to keep them in order.
6. The rapidity and certainty with which a flame can be lighted up or
extinguished at a great distance from the working point, admit of a code of
signals being planned on the principle of varying and measuring the duration
of the time of illumination and eclipse, and shewing lights through glasses of
different colors.
7. By a simple mechanical contrivance, the gas may be turned on to or off
from the signal burners, and lighted up or extinguished by the action of a
train passing over the rail as it approaches and leaves a station, or at any
point on the line as it passes along.
Having now described the nature of my said Invention and the mode of
performing the same, I have to observe that the various modes, as herein-
before described, in which it may be used and carried into effect, are exempli-
fications of its application in practice; but I do not limit myself to the
arrangements and details herein-before described and referred to, and I would
have it understood that the principles of my said Invention may be applied in
other modes and for other purposes, of which the details and arrangements
admit of many variations.
What, however, I do claim as my Invention, and I therefore consider to
be secured to me by the before in part recited Letters Patent is,
First, the principle of making signals by alternately igniting and extin-
guishing jets of illuminating gas.
Second, the general arrangement for carrying the said principle into effect
by the conveyance of gas through branch pipes from a gas main to a burner,
in combination with the action of a shut-off cock and a spring valve, as
herein-before described.

page_text: Third, the use of a spring valve to regulate differential pressures in a gas
main and its branch pipes, and prevent the entrance of atmospheric air into
the branch pipes, as herein-before described.
Fourth, the mode and general arrangement of making the alternating
principle of igniting and extinguishing gas jets applicable to the same uses and
purposes as revolving lights for lighthouses or telegraphic signals on land or
at sea, as herein-before described or referred to.
Fifth, the use of clockwork or any other mechanical means for opening and
shutting the cock or valve of a pipe supplying gas to a burner, and for regula-
ting the alternating or intermittent ignition or extinction of gas jets, as herein-
before described or referred to.
Sixth, the mode of using gas on the principles of my said Invention for
signals on board ships, as herein-before described or referred to.
Seventh, the plan and general arrangement of applying the principles of
my said Invention to enable railway trains in motion, as they pass over the
rails, to cause the exhibition at given points of signal lights for limited periods
of time, by means of the action of a passing train, on an apparatus constructed
and arranged to supply a gasholder with gas, as herein-before described and
referred to.
Eighth, the use of a permanent flame for igniting jets of gas instantaneously
as they issue from a burner, as herein-before described.
In witness whereof, I, the said Samuel Thomas Cooper, have hercunto
set my hand and seal, the Thirtieth day of August, One thousand
eight hundred and fifty-ninc...

page_text: sigrants may ve estavushed on the une, from distance to distance.
B The valve or cock regulating the supply of gas from the main.
C The branch pipe supplying gas to the signal burners; D a spring valve at the end of the
branch pipe, close to the signal burners, E a box containing the spring valve D. Fa small jet of
gas kept continuously burning. Ga nine supplying gas, either from the main, or b
the branch pipe, to
the flame F. HH signal burners with the gas turned off, II. signal burners with the
ignited, being turned on.
gas