IMPROVEMENTS IN APPARATUS FOR TRANSMITTING SIGNALS AND FOR OPENING AND CLOSING COCKS AND VALVES, WHICH IMPROVEMENTS ARE SPECIALLY APPLICABLE TO THE PREVENTION OF RAILWAY ACCIDENTS
Year: 1873

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Gentleman, for the Invention of
"IMPROVEMENTS IN APPARATUS FOR TRANSMITTING SIGNALS AND FOR OPENING
AND CLOSING COCKS AND VALVES, WHICH IMPROVEMENTS ARE SPECIALLY
APPLICABLE TO THE PREVENTION OF RAILWAY ACCIDENTS."-A communi-
cation from abroad by Jean Dedier Digney, Théodore Sebastien
Digney, Henry Lartigue, and Henri Forest, all of Paris, in the
Republic of France.
Sealed the 28th March 1873, and dated the 21st January 1873.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on
the 21st January 1873.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
5 of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN APPARATUS FOR TRANSMITTING SIGNALS AND
FOR OPENING AND CLOSING COCKS AND VALVES, WHICH IMPROVEMENTS ARE SPECIALLY
APPLICABLE TO THE PREVENTION OF RAILWAY ACCIDENTS," a communication to
me from abroad by Jean Dedier Digney, Théodore Sebastien Digney,

page_text: Henry Lartigue, and Henri Forest, all of Paris, in the Republic of
France, to be as follows:-
This Invention relates to a peculiar combination and arrangement of
steam whistle and electro-magnetic apparatus for transmitting signals,
which arrangement is more particularly applicable to locomotive engines
on railways for the purpose of warning the driver that any given signal
is turned against him in cases where, by reason of fogs, snow storms, or
other causes a difficulty exists in seeing the signals along the line, and
hence one of the causes of railway accidents, namely, running past a
danger signal is obviated.
The said Invention is also applicable to the transmission of signals
from the bridge to the engine room on board steamers, also from the
lower workings or galleries of mines to the surface, also to the opening
and closing of cocks or valves for steam air or liquid at long distances
in large works or manufactories.
"
As applied to railways and locomotive engines thereon for the purpose
of intimating or signalling to the driver that a signal is set to "danger
the following is the mode of carrying out this Invention:-To any
convenient part of the boiler there is fitted a steam whistle, the cock or
valve of which is opened by the action of a helical spring, and is kept
shut by an electro-magnet by preference of the construction known as
Hughes' electro-magnet. The valve of the steam whistlo is connected
to a lever, which is again connected by a rod to a second lever contained
inside a box, which box also contains the electro-magnet.
The helical spring which surrounds the before-mentioned connecting
rod tends to depress the said levers and thereby to open the valve and
sound the steam whistle so soon as the lower lever, which is held up by
the electro-magnet, is released or permitted to descend. This release of
the said lever is accomplished by sending an electric current in a certain
direction through the coils of the magnet, which is effected in the
following manner :—
One end of the wire of the coils on the magnet is connected to the
engine, and establishes contact with the earth through the wheels and
the rails, the other end is connected to an insulated metallic brush
situate in any convenient part of the engine. On the railway line,
either between the rails or at one side thereof, there is fitted a fixed

page_text: metallic contact consisting, for example, of a wooden beam covered with
any good insulating or non-conducting composition and faced on its
contact surface with a sheet of copper, which copper is in communi-
cation by means of a wire with the positive pole of a battery. The
negative pole of the said battery is in communication, by means of
another wire, with a commutator on the signal post, from which a wire
leads direct to earth. The commutator is so arranged that so long as
the signal is at "line clear" the connection between the battery and
carth is broken, but when the signal is set to "danger" the commutator
brings the negative pole of the battery in direct communication with
earth. Whilst in this condition, when an engine fitted with tho
apparatus above described arrives at the fixed contact which is placed at
any given distance in advance of the danger signal the metallic brush
will, by the fact of its passing in contact with the said fixed contact
surface, establish a circuit through the electro-magnet, which will
momentarily release the lower lever and allow the helical spring to
depress both lovers and thereby open the cock or valve of the steam
whistle, causing the same to be sounded until the lower lever has been
elevated again by the engine driver so as to bring it under the attractive
influence of the electro-magnet, which retains it elevated, and keeps
the valve closed till the whistle is again called into action. If the signal
be not turned on or set to "danger" no circuit is established, and the
passage of the metallic brush over the fixed contact surface will produce
no result.
The metallic brush may be dispensed with for other signalling
purposes or when it is simply desired to open or close valves or cocks at
long distances by electro-magnetic agency, but in all cases the same or
equivalent arrangement of electro-magnet levers and spring will be
employed, the circuit being established in any known manner.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of January, in the
year of our Lord One thousand eight hundred and seventy-three, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Henry Johnson, Her special license
that I, the said John Henry Johnson, my executors, administrators,
and assigns, or such others as I, tho said Jolm Henry Jolinson,
my executors, administrators, or 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 "IMPROVEMENTS IN
APPARATUS FOR TRANSMITTING SIGNALS AND FOR OPENING AND CLOSING COCKS AND
VALVES, WHICH IMPROVEMENTS ARE SPECIALLY APPLICABLE TO THE PREVENTION OF
RAILWAY ACCIDENTS," a communication to me from abroad by Jean Dedier
Digney, Theodore Sebastien Digney, Henry Lartigue, and Henri Forest,
all of Paris, in the Republic of France, upon the condition (amongst others)
that I, the said John Henry Johnson, my executors or administrators,
by an instrument in writing under my hand and seal, 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 John Henry Johnson, 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, reference being had to the accompanying
Drawings, and to the letters and figures marked thereon, that is to
say:
The said Invention relates to a peculiar combination and arrangement
of steam whistle and electro-magnetic apparatus for electro-magnetic
apparatus for transmitting signals, which arrangement is more par-
ticularly applicable to locomotive engines on railways for the purpose of
warning the driver that any given signal is turned against him in cases
where, by reason of fogs, snow storms, or other causes, a difficulty
exists in seeing the signals along the line, and hence one of the causes of
railway accidents, namely, running past a danger signal is obviated.

page_text: The said Invention is also applicable to the transmission of signals
from the bridge to the engine room on board steamers, also from the
lower workings or galleries of mines to the surface, also to the opening
and closing of cocks or valves for steam, air, or liquid at long distances
in large works or manufactories.
As applied to railways and locomotive engines thereon for the purpose
of intimating or signalling to the driver that a signal is set to "danger,"
the following is the mode of carrying out this Invention:-To any
convenient part of the boiler there is fitted a steam whistle, the cock or
valve of which is opened by the action of a helical spring, and is kept
shut by an electro-magnet by preference of the construction known as
Hughes' electro-magnet. The valve of the steam whistle is connected
to a lever, which is again connected by a rod to a second lever contained
inside a box, which box also contains the electro-magnet.
The helical spring which surrounds the before-mentioned connecting
rod tends to depress the said levers and thereby to open the valve and
sound the steam whistle so soon as the lower lever, which is lield up by
the electro-magnet, is released or permitted to descend. This release of
the said lever is accomplished by sending an electric current in a certain
direction through the coils of the magnet, which is effected in the
following manner :—
One end of the wire of the coils on the magnet is connected to the
engine, and establishes contact with the carth through the wheels and
the rails, the other end is connected to an insulated metallic brush
situate in any convenient part of the engine. On the railway line,
citler between the rails or at one side thereof, there is fitted a fixed
metallic contact consisting, for example, of a wooden beam covered with
any good insulating or non-conducting composition, and faced on its
contact surface with a sheet of copper, which copper is in communi-
cation by means of a wire with the positive pole of a battery. The
magetic pole of the said battery is in communication by means of
another wire with a commutator on the signal post, from which a wire
leads direct to carth. The commutator is so arranged that so long as
the signal is at "line clear" the connection between the battery and
earth is broken, but when the signal is set to "danger" the commutator
brings the negative pole of the battery in direct communication with
earth. Whilst in this condition, when an engine fitted with the
apparatus above described arrives at the fixed contact which is placed

page_text: at any given distance in advance of the danger signal the metallic brush
will, by the fact of its passing in contact with the said fixed contact
surface, establish a circuit through the electro-magnet, which will
momentarily release the lower lever and allow the helical spring to
depress both levers, and thereby open the cock or valve of the steam 5
whistle, causing the same to bo sounded until the lower lever has been
elevated again by the engine driver, so as to bring it under the attractivo
influence of the clectro magnet which retains it clevated and keeps the
valve closed till the whistle is again called into action. If the signal be
not turned on or set to " danger" no circuit is established, and the 10
passage of the metallic brush over the fixed contact surface will
produce no result.
The metallic brush may be dispensed with for other signalling
purposes or when it is simply desired to open or close valves or cocks at
long distances by electro-magnetic agency, but in all cases the same or 15
equivalent arrangement of electro-magnet levers and spring will bo
employed, the circuit being established in any known manner.
And in order that the said Invention may be fully understood I shall
now proceed more particularly to describe the same, and for that purposo
shall refer to the several Figures on the annexed Sheet of Drawings, 20
the same letters of reference indicating corresponding parts in all the
corresponding Figures.
As applied for uso on a railway, the arrangement consists of a steam
whistle A (Figure 1) placed on the locomotive B and sounded at the
time the engine passes a spot at a determined distance from a disc O 25
(Figure 2) set to "danger" at whatever speed the engine may bo
running. The apparatus is composed of a whistle A (Figure 3) of hard
brass, having a receiver and lever D, such whistle being in communi-
cation with the boiler and carried on a metal box E attached to the
engine. This box contains another lever F parallel with the lever of the 30
whistle to which it is connected. This lever is subjected to the action of
a powerful spring, which tends to depress it, and by so doing to admit of
the passage of the steam, but it carries at the extremity of its arm a
pallet G of soft iron in contact with an electro-magnet H on Huglics'
system, composed as is well-known of a fixed horse-shoc magnet, the 35
branches of which are lengthened by cylinders of soft iron surrounded
by bobbins of wire covered with silk. These cylinders become the poles
of the magnet and their attraction counterbalances the action of the

page_text: spring. If an electric current be caused to pass in the bobbins of the
electro-magnet in a determined direction the attraction ceases moment-
arily, the lever falls, and the whistle is sounded until the driver, by
pressing on a plug K projecting from the lower part of the box, stops it
by bringing back the lever into its original position, that is to say, into
contact with the electro-magnet.
The action of the clectricity is produced in the following manner,
vizt.-The wire of the bobbin is connected at one end with the body
of the engine (as shewn at T¹) and by the intervention of the wheels
and rails with the earth; the other extremity is prolonged by a wire L',
which descends beneath the engine and terminates at a metal brush M
(Figure 1) insulated and fixed in such a position that its wires (which
are composed of hard brass) extend a few inches beyond the most
projecting portions of the engine. This brush is shewn to a scale of
half size in plan and section in Figures 4 and 5 respectively.
On the line at the desired distance from the disc a piece N (Figures
2, 6, 7, and 10) which is designated a contact piece is disposed. This is
composed of a wooden sleeper placed longitudinally between the rails
and carried by iron supports O at such a height as to be beyond the reach
of the lowest portions of the locomotive. This wooden sleeper, which is
coated with an insulating material, is provided on the top with a sheet
of copper, which through the intervention of a conducting wire L of
any required length is placed in communication with the positive pole
of a pile.
The negative pole is connected by a wire T with a commutator P
(Figure 2) which puts it in connection with earth when the disc signal
is turned to "danger" and isolates it on the contrary during the wholo
of the time that the disc indicates "line clear."
The majority of the discs are already provided with this commutator,
which, according to the existing system, brings a gong into action so
that the wire from this gong and that from the fixed contact being
moreover connected to the positive pole of the same pile, the intro-
duction of this apparatus may be said to entail no addition to or
modification in the existing disc on whatever system it may be
constructed.
As the engine passes along the brush M rubs with considerable force
against the fixed contact, if the disc is at “line clear
" no effect is

page_text: produced, but if the disc is turned to "danger" the copper plate is
brought by this means in communication with a source of electricity,
and on the locomotive passing the metal brush M coming in contact
with the copper plate completes the circuit through the intervention of
the bobbins the body of the engine and the rails, and the whistle is
sounded.
This result has never failed to take place in all weathers and at speeds
even as high as nearly 70 miles per hour, even when the copper plate
was purposely covered with a thick layer of ballast, which the brush
removed whilst establishing the contact. It is not necessary, therefore,
to take into consideration an obstacle much less difficult to overcome
caused by a layer of snow in our climates. On the other hand the
apparatus has never been unduly disturbed during tho working by reason
of the jerks or shocks of the engine. Its simplicity also, and the
strength of its construction, prevent all approliension of any subsequent
derangement. As it is of very small dimensions the place where it is
fixed may be selected according to the type of the engines. It requires
no attention on the part of the driver.
The brushes employed shew scarcely any trace of wear after long uso
under unfavourable conditions resulting from the accumulation of ballast
on the way, which is daily under repair in a portion of the line experi-
mented upon.
The arrangement of the fixed contact hercin-before described is that
adopted on the North of France Railway, where the whole of the
distance discs are provided with electric bells. In the case of those
companies which have not the bells it is simply requisite to set up a pilo
near the disc, the positive pole of which pile is in communication with
the copper plate, whilst the negative pole is connected with a commutator
placed on the disc and effecting the completion of the circuit when the
disc is set to "stop" or danger." The fixed contact on the railway
referred to is disposed on the ground between the rails in the centre of
the way. In the case of those countries subject to licavy and continuous
snow storms the contact may be disposed laterally at a certain height
above the ground, as shewn in Figures 2, 8, 9, and 11, and in such a
position as to be beyond the reach of the most projecting portions of the
rolling stock; the brush would then be disposed at the side of the
locomotive, so that contact may take place every time the engine
passes.

page_text: It was originally doubted whether, by reason of the shortness of the
time of contact the action would be properly effected, the first experi-
ments were made with a length of contact of fourteen feet, which
admitted of the current passing for about one fourth or one fifth of a
second under the highest speeds. Experience has since demonstrated
that a certain result is arrived at with a length of not quite seven feet,
which length has been adopted.
In case of necessity the apparatus may operate without the aid of a
disc. The fixed contact may be placed at a great distance from a known
point, and by connecting an electric wire between this point and the
fixed contact the driver of the engine may be warned at any desired
distance.
In addition to the said signal this system of electro-automaton whistle
is susceptible of other applications. Thus when a driver backs a train
into a siding terminating in bumpers, by means of a special arrangement
the whistle may be caused to warn him at the moment when the first
vehicles arrive near the bumpers; the driver would then cease backing,
and a frequent cause of deterioration of rolling stock would thus be
avoided.
In the navy communication may be established by this means between
the officer of the watch and the engineer in cases where the engineer
may for the moment be away from the speaking trumpet, and it is
requisite to urgently call his attention.
In mincs a powerful signal may be given from the bottom of the
drifts to the engineer who is at the mouth of the shaft; also in factories
or large workshops a similar signal may be given from any point to the
stoker of the engine.
. Also, exclusively of the whistle, the lifting power of the apparatus may
be employed in works to open or close a steam valve, a safety valve, or a
gas or liquid cock, at whatever distance it may be situate therefrom.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used or
carried into effect, I would obscrve in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is,-
First. The peculiar combination of the automaton whistle, moveable
contact, and fixed contact for the purpose of warning the driver of a