IMPROVEMENTS IN-THE- CONSTRUCTION AND ARRANGEMENT OF ELECTRIC TELEGRAPHS, AND IN THE APPLICATION THEREOF
Year: 1855

page_text: TTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in
the County of Middlesex, and of Glasgow, North Britain, Gentleman, for
the Invention of "IMPROVEMENTS IN-THE- CONSTRUCTION AND ARRANGEMENT
OF ELECTRIC TELEGRAPHS, AND IN THE APPLICATION THEREOF."-A communi-
cation from the Chevalier Gaetano Bonelli, of Turin, in the 'Kingdom of
Sardinia, Director General of Sardinian Telegraphs..
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at
the Office of the Commissioners of Patents, with his Petition, on the
25th January 1855
-
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of Glasgow, North Britain, Gentleman, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN THE CONSTRUCTION AND
ARRANGEMENT OF ELECTRIC TELEGRAPHS, AND IN THE APPLICATION THEREOF,"
communication from the Chevalier Gaetano Bonelli, of Turin, in the Kingdom
of Sardinia, Director General of Sardinian Telegraphs; to be as follows:-
This Invention relates to a peculiar construction and arrangement of electric
telegraphic apparatus, and in the application of the same, so as to enable one
or more trains or engines, whether in motion or stationary, to correspond either
with each other or with a telegraph station, or with the policemen, pointsmen, or
other officials on the line. In carrying out this Invention, an insulated conductor
is used, which may be placed longitudinally between the two rails of the up and

page_text: down lines, and upon this conductor slides or runs a piece of metal or anti-
friction pulley, attached to the engine, tender, or wagon, as the case may be,
and communicating with an electric telegraph apparatus placed thereon. This
apparatus communicates in its turn with the earth through the wheels of the
locomotive and the rails of the line, or by a separate piece of metal sliding
on the rails. A circuit is thus formed by the insulated conductor, the
telegraphic apparatus on the locomotive or carriage, and the earth. The
locomotive or carriage is provided with a small battery, the current. from
which passes along the before-mentioned circuit by suitable connections, as in
the ordinary telegraphs. The telegraphic apparatus may be of any of the well-
known arrangements, and the arrangement of the insulated conductor may be
varied according to circumstances, such, for example, as a change of line or a
level crossing. The insulated conductor may either be placed in communica-
tion at its extremities with a telegraph station, thereby affording facility for
corresponding with locomotives on the line, or the ends of the conductor may
be simply bent down into the earth. Conductors so laid down may be sub-
stituted for the present mode of carrying telegraphic wires, being less expensive
than the plan at present adopted. As each engine or train on the line will be
furnished with complete apparatus necessary for sending or receiving messages,
it is obvious that one engine or train may readily correspond with the next
train, either before or behind, and learn thereby not only the locality of such
train, but make known in return the precise locality in which it is itself
situated. In cases of obstruction on the line, by laying a bar of iron or other
conductor across the rails in front of the obstruction, and in such a manner as
to be in contact with the conductor and one of the rails, a a constant current
will be sent through the locomotives or trains, and the engine drivers will know
by the deflections of the needles that the line is obstructed, and that, con-
sequently, a good look out and great care will be required. An engine or train
may also obviously correspond with the telegraph station, and learn whether the
line is clear at such station.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on the
25th July 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex, 3
and of Glasgow, North Britain, Gentleman, send greeting..

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fifth day of January, in the year of our Lord One
thousand eight hundred and fifty-five, in the eighteenth 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, the said John Henry
Johnson, 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
THE CON-
STRUCTION AND ARRANGEMENT OF ELECTRIC TELEGRAPHS, AND IN THE APPLICATION
THEREOF," a communication from the Chevalier Gaetano Bonelli, of Turin,
in the Kingdom of Sardinia, Director General of Sardinian Telegraphs, upon
the condition (amongst others) that I, the said John Henry Johnson, 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 per-
formed, 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 construction and arrangement of
electric telegraphic apparatus, and in the application of the same, so as to
enable one or, more trains or engines, whether in motion or stationary, to
correspond either with each other or with a telegraph station, or with the
policemen, pointsmen, or other officials on the line. In carrying out this
Invention, an insulated conductor is used, which may be placed longitudinally
between the two rails of the up and down lines, and upon this conductor is
made to slide or run a piece of metal or anti-friction pulley, attached to the
engine, tender, or waggon, as the case may be, and communicating with an
electric telegraph apparatus placed thereon. This apparatus communicates in
its turn with the earth through the wheels of the locomotive and the rails of
the line, or by a separate piece of metal sliding on the rails. A circuit is thus
formed by the insulated conductor, the telegraphic apparatus on the locomotive
or carriage, and the earth. The locomotive or carriage is provided with a small

page_text: battery, the current from which passes along the before-mentioned circuit by
suitable connections, as in the ordinary telegraphs. The telegraphic apparatus
may be of any of the well-known arrangements, and the arrangement of the
insulated conductor may be varied according to circumstances, such, for
example, as a change of line or a level crossing. The insulated conductor may
either be placed in communication at its extremities with a telegraph station,
thereby affording facility for corresponding with locomotives on the line, or the
ends of the conductor may be simply bent down into the earth. . Conductors
so laid down may be substituted for the present mode of carrying telegraphic
wires, being less expensive than the plan at present adopted. As each engine
or train on the line will be furnished with complete apparatus necessary for
sending or receiving messages, it is obvious that one engine or train may
readily correspond with the next train, either before or behind, and learn
thereby not only the locality of such train, but make known in return. the
precise locality in which it is itself situated. In cases of obstruction on the line,
by laying a bar of iron or other conductor across the rails in front. of the
obstruction, and in such a manner as to be in contact with the conductor and
one of the rails, a constant current will be sent through the locomotives or
trains, and the engine drivers will know by the deflections of the needles
that the line is obstructed, and that, consequently, a good look out and great
care will be required. An engine or train may also obviously correspond. with
the telegraph station, and learn whether the line is clear at such station.
And in order that the said Invention may be more readily understood, I
shall now proceed to describe and refer to the several Figures on the Sheet of
Drawings hereunto annexed..
.
Along the line a, b, in Fig. 1 of the Drawing, a bar of iron is laid, along
which slides a piece of metal d, suspended to the locomotive, which piece of
metal is in communication with the coil e, forming a part of the 'one needle
telegraphic apparatus of Wheatstone and Cooke, or other suitable 'arrangement,
the dial plate and working handle of which are under the eye of the attendant.
A wire c forms a communication with the earth, either by means of the wheels
of the locomotive, or by a piece of metal sliding along the rails.
Whether the locomotive be in inotion or not, if a current of electricity
arrives from a or b, it follows the route indicated by the arrows on the Drawing
from 1 to 5, and produces a deviation of the magnetic .needle, when it is
conveyed back again by the earth. Signals may in this manner be sent to
the locomotive from stations situated either in front or behind it.
If the locomotive receiving the signals carries a battery; the circuit from
which is interrupted at the point ; by means of a commutator between the

page_text: arrows 4 and 5 on the Drawing, (the wire being broken at this place,) it
will be found very easy to signal to other locomotives or to stations along
the line.
'
Fig. 2 of the Drawing represents a longitudinal elevation of a portion of the
line
; on which are arranged, first, a telegraphic station; second, three loco-
motives B, C, D, either in motion or at rest; and, third, a carriage E, left by
accident on the line.
Fig. 3 is a plan of this view. Between the rails r is fixed the insulated iron
conductor a, b, which rests upon supports f of earthenware or other non-
conducting material fixed upon the transverse sleepers of the railway, as shewn
in the details, Figs. 4 and 5.
At Fig. 9 is represented another description of earthenware support, which
is fixed to the cross pieces by means of a suitable screw pin. It would be
advisable, in order to insure perfect insulation, that all the faces of this bar,
except that in communication with the locomotive, should be coated with some
bituminous substance. At level crossings it is necessary to place this bar below
the rails, in order to protect it from carts or carriages that may be passing
over it. The transverse section at Fig. 6 shews this arrangement, in which
case the earthenware supports are fixed upon transverse pieces of wood h. I
may here observe that this arrangement of conductor may be employed in
ordinary telegraphs in place of the wires now in use, over which it possesses
the advantages of economy and safety. In this case the bar would be entirely
covered with tar, and might be protected by a sort of cover, as shewn in dotted
lines, in Fig. 4.
The ends of the bars which form the insulated conductor
must of course be in perfect metallic contact; they are, therefore, united by
means of screws, and it is found advisable to introduce at the joint a piece of
sheet tin. At places where the line changes or branch lines occur, the arrange-
ment represented at Fig. 7 is used; the bar a, b, is interrupted, or its continuity
broken, and the communication between the two ends of the bar is effected
by means of the rod k, coated thickly with tar, and passing under ground.
In passing along the conductor the slider encounters the bar 1, the object
of which, however, is thereby to sustain it, this bar being quite independent of
the conductors a, b. The bar is in connection with the points, and turns with
them. By this arrangement, the current of electricity is interrupted during the
time that the slider passes over the bar l, but this interruption is, however, of
such short duration that the inconvenience is immaterial.
For telegraphic stations the conductor a, b, may be similarly interrupted,
and the bar 7 placed in communication with the telegraphic apparatus, this bar
being thus made à part of the circuit....It is proposed, however, to make use

page_text: of currents derived from other sources, instead of making the principal current
pass through all the spirals of the coils of the telegraphic apparatus, which
would lessen its power. By this arrangement the signals sent from either
stations or locomotives would be repeated at all the other stations along the
line. It will be seen, in fact, that the current starting off from the first station
must necessarily produce its effect on all the coils of the different apparatus
along the line.
The entire current which starts from any particular apparatus encounters no
other external resistance than that of the apparatus from which it starts, not a
fraction of this resistance being altered by the number of other apparatus on
the line. The resistance of the spiral of the station from which the message
is sent may be easily avoided by the employment of a key or second conductor,
which is introduced into the circuit at the moment of transmission only by the
motion of the hands of the manipulator, and which receives a convenient
quantity of the transmitted electricity. Although an insulated conducting bar
of large section may be found very advantageous, as by this the resistance
to the passage of the electricity is almost entirely obviated, yet it only allows
of derived currents of electricity being used, which considerably lessens the
necessary force of the batteries, instead of forcing the current to traverse all
the spirals of the coils. This system will work, however, even if a diameter
is given to the conducting bar equal to the diameter of one of the telegraphic
wires in ordinary use, that is to say, if one of such wires be substituted for it.
In this case, as the resistance of the conductor is no longer inconsiderable;
the stations or locomotives can only correspond with a limited number of other
stations or locomotives, that is to say, only with the nearest ones.
The slider, namly, the piece of metal suspended to the locomotive, establishes
the communication between the conductor and the telegraph apparatus. This
slider may be of various forms; that which is represented in Fig. 8 is com-
posed. simply of a bar of iron of a rectangular section m, terminated at the
lower end by the curved and grooved piece n, which rests upon the insulated
conductor.
The bar m moves in an earthenware guide O, fixed to the frame of the
engine or wagon, and it is furnished with an enlargement at its upper extremity
p, which limits its descent. The wire connected to the top of the slider is in
communication with the telegraphic apparatus on the engine. The bar m,
which is of sufficient weight to keep it constantly pressed upon the conductor,
carries two arms m', to which are jointed the sliding pieces 7, furnished with
some suitable material for keeping the conducting bar clean.
In order to remove the snow, a blade is fixed in place of the rubbers, which

page_text: effectually remove any snow that may rest upon the bar. The piece n may
also, if desirable, be replaced by a roller, and the pressure which it exerts may
be increased by means of a spring.
In railways composed of two lines of rails, a single conductor may be used,
placed between the two lines, instead of a separate conductor for each pair of
rails; in this case the instruments at the stations will not require two needles.
The slider must in this latter case be fixed at the side of the locomotive,
and may be kept pressed against the side of the conductor by means of a
bent lever and counterpoise weights, or by a spring, or any other suitable
arrangement. In order that no ill effects may arise from the meeting of the
trains, the sliders of the different trains press against two different sides of
the conducting bar. By this arrangement trains on different lines of rails may
communicate with each other.
With regard to the communication with the earth, this may easily be
effected by means of any good conducting material pressing against the axle of
one of the pairs of wheels of the engine, but I prefer the driving wheels. If
required, a piece of metal may be made to slide against the rails in place of
passing the current through the wheels of the engine. In using this apparatus,
supposing that the locomotive B is about to start from the station A, the
engineer commences by moving his manipulator handles, where, if there are
no other locomotives on the line either before or behind him, and if the bar
be properly insulated, no deviation in the needles will take place. The
engineer is then satisfied that he can proceed in perfect safety. But generally
there are locomotives on some part of the line, and in this case of course the
needle would deviate; the engineer of the locomotive C, however, would also
perceive the deviation of his needle, and he would instantly reply, stating in
what part of the line he was. The first would then know whether he could
safely proceed or not.
The two engineers of the locomotives B and C may communicate with one
another whether they are at rest or in motion, and the signals which they
exchange will be understood by all the trains on the same line. If, in front of
the station A, the conducting bar be separated and the two ends be put in
communication with the wires of the instrument at that station, thus allowing
the current to circulate through it, signals may then be exchanged between
the station and the trains which are near to it, which may thus ask for instruc-
tions, or for anything else that may be required. In the railways composed of
two pairs of rails, each possessing a conducting bar of its own, it is necessary
that an instrument of two needles should be used at the station, one needle for
cach conductor.

page_text: '
If for any reason.it is necessary to abandon any carriages upon the line,
approaching trains may be warned of their danger by simply placing a bar of
iron in such a manner as to touch both the conducting bar and the rails. The
engineer of the approaching train would perceive that his needle was deviating,
although no answer could be obtained to his signals; he would then under-
stand that an obstacle existed, and that it was necessary to proceed with
caution. But for this purpose it would be necessary that the extremities of
the conducting bar should be insulated instead of entering the earth. The
force with which the needle deviated would enable the engineer to calculate
roughly the proximity of the obstacle. If it is required to communicate
simultaneously with two trains on different lines, it is simply necessary to put
the extremities of the conducting bars of the two lines into communication, and
to proceed as before.
An alarum may be placed on the locomotives, in the same manner as in
ordinary telegraphs. Independently of the great utility of this arrangement
when applied to moving telegraph stations, that is to say, to locomotives, it
possesses, in its application to ordinary telegraphs, the following important
advantages:
1st, its slight clevation above the ground and the simplicity of its supports.
2nd, the section of the conducting bar being larger than that of the telegraph
wires in ordinary use, the resistance offered to the passage of the electricity is
very much reduced.
3rd, the general arrangements of the telegraph stations in which each instru-
ment communicates with the earth, and is actuated by a special derived current
instead of a direct current.
4th, the facility with which it may attended to and repaired.
5th, the economy in the batteries, since messages to be transmitted through
great distances require no more power than those for small distances.
6th, the extreme facility with which, by this system of derived currents, com-
munications may be effected with any number of stations.
7th, the insulated action of each instrument, by which it is not necessary, as
in the existing system, for intervening stations to interrupt communications.
8th, the possibility, in its application to railways, of considerably reducing the
number of fixed telegraphic stations, which, according to this system, would
be simply placed at stations of importance.
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 observe, in conclusion, that I do not confine or restrict
myself to the precise details or arrangements which I have had occasion to

page_text: describe or refer to, as many variations may be made therefrom without
deviating from the principles or main features of the said Invention; but
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 system or mode of effecting a communication between two or
more trains, and between trains and stations, by the use of an insulated con-
ducting bar and derived or direct currents, as herein-before described.
Second, the system or mode of working the apparatus in the manner and by
the arrangement herein-before described, either for the purpose of trans-
mitting and receiving messages to or from railway trains or locomotives,
whether in motion or stationary, or as an ordinary electric telegraph.
In witness whereof, I, the said John Henry Johnson, have hereunto
set my hand and seal, the Twenty-fifth day of July, One thousand
eight hundred and fifty-five.
J. HENRY JOHNSON. (L.S.)