IMPROVE- MENTS IN ELECTRIC TELEGRAPHS
Year: 1878

page_text: LETTERS PATENT to Edward Alfred Cowper, of No. 6, Great George Street,
Westminister, in the County of Middlesex, for the Invention of IMPROVE-
MENTS IN ELECTRIC TELEGRAPHS."
Sealed the 4th October 1878, and dated the 15th June 1878.
PROVISIONAL SPECIFICATION left by the said Edward Alfred Cowper at
the Office of the Commissioners of Patents on the 15th June 1878.
EDWARD ALFRED COWPER, of No. 6, Great George Street, Westminster, in the
County of Middlesex. IMPROVEMENTS IN ELECTRIC TELEGRAPHS."
..
My Invention relates to a system of telegraphing and apparatus for carrying it
into effect, according to which I produce at one station a copy, or an approximate
copy, of matter written or traced at another station.
The principle on which my system is founded is that of compounding the move-
ments of a point in two directions, the one at right angles, or at some other desired
inclination to the other, the actual movement of the point being the resultant of
the two movements.
In order to apply this principle to telegraphy I employ at the one station a
sending instrument, in which a pen or other style is moved so as to write or trace
letters, figures, or other symbols, on a moving paper or other surface; and at the
other station I employ likewise an ink tube, brush, or other tracer, presenting little
resistance, so as to trace on a moving paper or other surface letters, figures, or other
symbols, similar, or approximately similar, to those traced at the sending station.
I make the movements of the tracer at the receiving station accord or nearly
accord with those at the sending station in the following manner:-The sending
tracer moves two contact makers, the one in a line at right angles or other desired
inclination to the line of the other. Each of these contact makers moves over a
set of stepped or graduated conductors, so as to send into line currents of greater
or less force, or subject to less or greater resistance, according to the extent of the
movement. By the one contact maker currents are sent into the one of two lines
which connect the sender to the receiver, and by the other contact maker currents

page_text: are sent into the other of these two lines. At the receiving station the tracer is
moved in two directions, at right angles or other desired inclination to one another
by means of a pair of polarised armatures, coils mounted in a magnetic field, or
other known instruments that move in obedience to electric currents.
The one of these instruments is actuated by the currents sent into the one line,
and the other instrument is actuated by the currents sent, into the other line.
According as these currents vary in their strength or in the resistance opposed to
them, as determined by the movements of the sending tracer, so the excursions
made by the receiving tracer in the two directions are varied, and thus the marks
made by it are caused to resemble, or approximately resemble, those made by the
sending tracer.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edward Alfred Cowper in the Great Seal Patent Office on the 14th
December 1878.
EDWARD ALFRED COWPER, of No. 6, Great George Street, Westminster, in the
County of Middlesex. "IMPROVEMENTS IN ELECTRIC TELEGRAPHS."
My Invention relates to a system of telegraphing and apparatus for carrying it
into effect, according to which I produce at one station a copy, or an approximate
copy, of matter written or traced at another station.
The principle on which my system is founded is that of compounding the move-
ments of a point in two directions, the one at right angles, or at some other desired
inclination to the other, the actual movement of the point being the resultant of
the two movements.
In order to apply this principle to telegraphy I employ at the one station a
sending instrument, in which a pen or other style is moved so as to write or trace
letters, figures, or other symbols, on a moving paper or other surface; and at the
other station I employ likewise an ink tube, brush, or other tracer, presenting little
resistance, so as to trace on a moving paper or other surface letters, figures, or
other symbols, similar, or approximately similar, to those traced at the sending
station.
I make the movements of the tracer at the receiving station accord or nearly
accord with those at the sending station in the following manner :-The sending
tracer moves two contact makers, the one in a line at right angles or other desired
inclination to the line of the other. Each of these contact makers moves over a
set of stepped or graduated conductors, so as to send into line currents of greater
or less force, or subject to less or greater resistance, according to the extent of the
movement. By the one contact maker currents are sent into the one of two lines
which connect the sender to the receiver, and by the other contact maker currents
are sent into the other of these two lines. At the receiving station the tracer is
moved in two directions, at right angles or other desired inclination to one another,
by means of a pair of polarised armatures, coils mounted in a magnetic field, or
other known instruments that move in obedience to electric currents.

page_text: The one of these instruments is actuated by the currents sent into the one line,
and the other instrument is actuated by the currents sent into the other line.
According as these currents vary in their strength or in the resistance opposed to
them, as determined by the movements of the sending tracer, so the excursions
made by the receiving tracer in the two directions are varied, and thus the marks
made by it are caused to resemble, or approximately resemble, those made by the
sending tracer.
In operating according to my Invention the pin or other style is held in the
hand of the operator writing, who writes upon a strip of paper that is caused to
travel steadily under his pen, so that there is no occasion for him to move his hand
along on the paper, as is usual in writing; this paper slip however only serves to
enable the operator writing to see what he writes, as the paper is of no further use,
excent as a record of what has been written.
The pen or other style is connected by two light connecting rods (or it may be
by threads, if springs are added to keep the threads always tight) to the contact
apparatus for sending the currents of the required strengths; one connecting rod is
attached to one contact maker, which slides over a number of thin metal plates.
thus making contact with the one or two it may at the time rest on. The thin
metal plates are all insulated the one from the other, but are parallel to each other,
and very near together. They are all in connection with the line wire, though
through very different resistances; thus, No. 1 is in direct connection with the line
wire: No. 2 is in connection with No. 1, but through a considerable length of fine
wire or resistance coil; No. 3 again is in connection with No. 2, but through
another length of fine wire or resistance coil, and so on through the whole series of
thin metal plates,
so that when the contact maker, which is in connection with the
battery, slides on the plates it connects the battery with the one or two only that it
rests our, and so connects the line wire with the battery through all the resistances
interposed between plate No. 1 and the plate or plates the contact maker rests on
at the time, thus sending a current of any given strength into the line wire for
transmission to the receiving instrument at the other end of the line. Thus it is
evident that the strength of the current depends upon the position of the pin or
style at the moment whilst writing, and as the other connecting rod from the pin
or style is provided with a similar contact maker sliding over another set of thin
metal plates, at right angles or nearly so to the first, and connected in the same
manner with another line wire, it is clear that the two motions of the pen up
and down, and right and left, will convey two currents through the two line wires,
varying in strength according to the varying position of the pen with which the
operator is writing.
It is well known that to produce any curved line it is only necessary to vary the
amount of the motions of up and down, and right and left, and therefore it is only
necessary at the receiving end of the line to utilize the varying currents, and cause
them to reproduce the same amount of motion that originally caused them to be
sent of their relative strengths, in order to produce fac simile of the hand writing
of the operator sending the message. In such an arrangement it is not absolutely
necessary that the electric writing should be exactly of the same size as that
written by the operator, as it may be arranged to be larger or smaller, though of
course small electric writing requires less motion in the parts of the receiving
instrument than large, and therefore the instrument would be somewhat quicker in
action.
The receiving instrument is arranged to produce the two motions at right angles,
or other angle, to each other, by the action of the varying currents from the two
line wires. The half of the instrument for producing the varying amounts of
motion in one direction is arranged with a light soft iron plate or bar, either
suspended, as in a galvanometer, or mounted on very delicate bearings or supports
so as to turn very freely. This light bar is surrounded for a considerable portion of
its length, at each end, with a fixed coil of fine insulated wire, at such a distance
from if as just to allow of its vibration as far as required. Such coil is in

page_text: connection with one of the line wires, so that the light bar of soft iron is thus made
into an electro-magnet without being burdened with the weight of the coils of
wire which would, to some extent, hinder the rapidity of action.
On the outside of the coils stationary magnets are placed by the attraction and
repulsion of which the motions of the light bar are affected, and these magnets may
be either permanent steel magnets or electro-magnets maintained by their own
battery independent altogether of the line wire.
The varying motion of the light bar of soft iron is taken up by a light rigid or
flexible connection to the writing pen or style, which may be of any known con-
struction or material used for such purposes, but I prefer to use a common syphon
pen, or such an one as described in the Specification of the Patent granted to
William Clark, 19th September 1859, N° 2132, which has a little reservoir of ink
to supply it, the tube being so small that the ink will not run out of it, though it
will come out freely when the point touches the paper and moves on it, or when
the paper moves under the syphon pin. The long strip of paper is moved slowly
along under the pen at about the same rate as a person moves his hand across a
sheet of paper whilst writing.
The currents sent through the line wire by the sending instrument vary in
strength or power, and therefore cause the light bar of soft iron to move with
varying power by its attraction to the stationary magnets, and in order to cause it
to take its proper position according to each variation in power a varying
resistance is opposed to it, such as a spring which requires more power to
compress it the more it is compressed, so that the action of the soft iron bar.
combined with that of a precisely similar bar actuated by the second line wire, will
cause the position of the pen in the receiving instrument to follow the position
of the pen in the hand of the operator at the sending instrument, and thus form
the letters. The total strength of the spring or varying resistance can be
regulated at will, so that the letters formed by the pen shall be of the same
proportionate height and width as the letters written by the operator at the
sending instrument.
One convenient way of applying the varying resistance to the light bar of soft
iron is by placing a very light spring to pull at the end of the bar in the direction
of its length, but allowing of the motion of the bar which will thus cause the spring
to act with more and more leverage as it moves more out of line with the spring.
When so arranged there is required another spring to keep the connection with the
pen tight, if such connection is flexible, so that the pen may go backwards as well
as forwards over the paper, as the light bar of soft iron moves either one way or
the other. But the spring or variable resistance may be made to act both to give
the increasing resistance and the power to draw back the pen as well, if the spring
is made to pull by a flexible or jointed connection at a fixed point, the line of such
pull being parallel, or nearly so, to the light bar of soft iron, while another rigid or
Hexible connection from the end of the bar to the connection to the spring has the
pen attached to it at about the middle of its length, which arrangement will give
the same result as the two springs before described.
Another form of receiving instrument that may conveniently he used to give the
motion required to the tracer in one direction, is that of one or a pair of permanent
steel magnets or needles capable of being attracted by a stationary electro-magnet
or maguets either in one direction or the other, or constantly in one direction with
a varying force, according to the strength of the current passed through the wire of
the electro-magnet or magnets from the line wire.
The motion is communicated to the tracer by a rigid or flexible connecting rod
to allow of the motion of the tracer in the other direction at right angles or other
angle to the first, such second motion being obtained by a similar receiving instru-
ment, so that the two in combination may reproduce the motions of the sending
tracer, owing to its sending currents of varying strength through the two line wires
to the receiving instruments.
Another form of receiving instrument (though not so conveniently made of the

page_text: same power as the above) is constructed with coils of insulated wire around the
vibrating steel magnets or needles, in place of the electro-magnets as above, on the
principle of two common indicators or galvanometers, the tracer being actuated in
the two directions as before.
Another form is made by reversing the arrangement of the fixed and moving
parts and letting the coils move, and the steel magnets be fixed (or using electro-
magnets as the fixed magnets).
Another slight modification consists in using soft iron keepers in place of steel
magnets in either of the three above cases, but they are not so good for the purpose,
in consequence of less power being obtained; or two pairs of magnets and armatures,
such as described in the Specification to Clark's Patent, No. 2134, of 1859, may be
arranged to work at right angles and actuate the pen.
DESCRIPTION OF THE DRAWINGS.
In all cases the same letters refer to the same parts.
Fig. 1,Sheet I.,shews a plan of sending instrument:Fig. 2,Sheet I., is an elevation.
a is the pen or style, which is held in the hand of the operator, and carries two
wires a¹², in connection with two batteries; bis the travelling slip of paper
(upon which the message to be sent is written) driven by clockwork or other
mechanism at a uniform speed; c, c, are the two sets of thin metal plates, forming
the contact apparatus; d, d, are the light connecting rods, the ends of which form
the contact makers, sliding over the sets of contact plates c, c; f, f, are the sets of
resistance coils which are connected to the contact plates, there being one coil for
each plate (except the first plate of each set, which is connected directly to the line
wire).
Fig. 3. Sheet I., is an elevation to an enlarged scale of the thin metal plates
forming the contact apparatus; Fig. 4, Sheet I., is a plan of plates; and Fig. 5,
Sheet I., is an elevation of a single plate. Each plate has an insulated wire g
soldered into it to form the connection with its resistance coil, and these wires may
be arranged radially (as shewn), or in any other such manner that they will not
interfere with cach other. The plates are insulated from one another by means of
paper or other suitable non-conducting material.
Fig. 6, Sheet I., is a plan of the receiving instrument; Fig. 7, Sheet I., is an
elevation. h, h, are the light soft iron moveable plates or bars suspended in delicate
bearings; i, i, are the fixed coils surrounding the bars h, h, in which the said bars
are free to vibrate, and through which the varying currents from the line wires are
sent; j,j, j, j, are the four constant electro-magnets or permanent magnets, between
the poles of which the soft bars h, h, and their surrounding coils i, i, are placed;
kis a syphon pen suspended by a spring and set screw, or other convenient means
of adjustment from the bridge 1, and having its shorter end dipping into the ink
reservoir m; n,, are the light connecting rods or threads by which the motions of
et the bars h, h, are transmitted to the syphon pen k; o, o, are the fine springs
which supply the necessary resistance to the pen against the pull of the magnets by
means of the threads o¹, 02, 0, the latter of which is attached to the fixed post o³.
is the travelling slip of paper upon which the message is written by the syphon
pen; it is driven by clockwork or other suitable mechanical means at a uniform
relative speed to the paper in the sending instrument.
Fig. 8, Sheet II., shews a plan of part of the receiving instrument to a larger
scale; Fig. 9, Sheet II., a side view of the same; and Fig. 10, Sheet II., an end
view. is the light soft iron moveable plate or bar turning freely in the
bearings r, r, (if desired the bar may be suspended by threads in place of these
bearings), the fixed coils surrounding them; and j, j, the constant electro-
magnets for which permanent magnets may be substituted if desired.
It will be seen that the permanent magnets being arranged in diagonal positions,
as shewn, can be adjusted relatively to the needle h.
Having thus described the nature of my Invention, and in what manner the

page_text: same is to be performed, I wish it to be understood that I do not limit myself to
the arrangement herein described for carrying the same into effect, as it will be
readily understood that the before-described method of operating may be carried
out in various ways, but I claim:-
First. Effecting at a receiving station the reproduction of characters written or
marked at a sending station by means of electric currents varied in force by the
movements of the sending style or tracer, so as to produce correspondingly varied
movements of the receiving style or tracer.
Second. In operating in the manner set forth in the preceding claim, causing the
sending style or tracer to transmit two distinct currents of varying strength through
separate line wires, so as to produce two motions in different directions at an angle
to each other in the receiving style or tracer, substantially as herein described.
Third. In operating in the manner set forth in the preceding claims, effecting
the variation of the force of the currents according to the movements of the sending
styler or tracer by means of contact pieces connected thereto and to the circuit in
such manner that, according to the position of the tracer, varying resistances are
included in or excluded from the circuit, substantially as herein described.
Fourth. In operating in the manner set forth in the preceding claims, causing
the variations in the currents transmitted by the sending style or tracer to impart
correspondingly varied motions to armatures, coils, magnets, or their equivalents, so
connected to the style or tracer at the receiving station that such style or tracer is
thereby made to reproduce the characters marked by the sending style or tracer,
substantially as herein described.
Fifth. The use for operating in the manner set forth in the preceding claims, of
apparatus arranged and operating substantially as herein described with reference
to the accompanying Drawings.
In witness whereof, I, the said Edward Alfred Cowper, have hereunto set my
hand and seal, this Thirteenth day of December, in the year of our Lord
One thousand eight hundred and seventy-eight.
EDWARD ALFRED COWPER. (L.S.)