IMPROVEMENTS IN SUBMARINE ELECTRIC TELEGRAPH
Year: 1860

page_text: LETTERS PATENT to Claude Marie Guillemin, of No. 7, Rue Madame,.
Paris, M.D., for the Invention of "IMPROVEMENTS IN SUBMARINE ELECTRIC
TELEGRAPH."
Sealed the 6th November 1860, and dated the 16th May 1860.
PROVISIONAL SPECIFICATION left by the said Claude Marie Guillemin
at the Office of the Commissioners of Patents, with his Petition, on
the 16th May 1860.
I, CLAUDE MARIE GUILLEMIN, of No. 7, Rue Madame, Paris, M.D., do
hereby declare the nature of the Invention for "IMPROVEMENTS IN SUBMARINE
ELECTRIC TELEGRAPHS," to be as follows:-
This Invention has for its object improvements in submarine electric
telegraphs. In submurine electric telegraphs great difficulty is caused by
induction between the conducting wire or strand of wires and the external
water or the metallic coating of the cable, which are separated the one from
the other by but a comparatively thin layer of insulating material..
According to my Invention I employ a cable consisting of a conducting
wire or strand,suitably covered with insulating material,and around this wire
is placed a metal casing for the conducting wire or strand, and its insulating
covering. This metal casing should be insulated with the same care as the
conducting wire, and the cable is finished with exterior protecting wires or
otherwise, as may be required.

page_text: Before transmitting a signal through the cable, one end of the insulated
metallic casing, viz., that at the transmitting station, is placed in connection
with one pole of a battery, and the circuit is completed through the metallic
casing and the earth; the current passing induces into the conductor
electricity of opposite polarity to that transmitted through the casing. When
a signal is to be transmitted, the contact with the casing is discontinued, and
contact is made with the conductor with the other pole of the same or another
battery, and the signal is transmitted; as soon as this is effected the conductor
is again disconnected from the battery, and the connection between the battery
and the casing is immediately re-established; this prevents the charge
running out of the wire when its connection with the battery is broken, and
the delay arising from the necessity of charging the wire for each signal is
avoided. would remark that many methods may be resorted to for pro-
ducing a metallic casing around the conductor and its insulating covering.
Several conducting wires may be used in the same cable as hitherto, but
they should be all insulated from each other, and each of them should be
worked as above described.
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said Claude Marie Guillemin in the Great Seal Patent
Office on the 16th November 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CLAUDE
MARIE GUILLEMIN, of No. 7, Rue Madame, Paris, M.D, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixteenth day of May, in the year of our
Lord One thousand eight hundred and sixty, in the twenty-third year of
Her reigu, did, for "Herself, Her heirs and successors, give and grant
unto me, the said Claude Marie Guillemin, Her special licence that I,
the said Claude Marie Guillemin, my executors, administrators, and assigns,
or such others as I, the said Claude Marie Guillemin; my executors,
administrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend, within
the United Kingdom of Great Britain and Ireland, the Channel Islands, and
Isle of Man, an Invention for "IMPROVEMENTS IN SUBMARINE ELECTRIC TELE-
GRAPHS," upon the condition (amongst others) that I, the said Claude Marie
Guillemin,my executors or administrators, by an instrument in writing under

page_text: my, or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the sume 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 Claude Marie Guillemin, do hereby.
declare the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
The condensation of electricity which is produced during the passage of a
current in submarine cables is the greatest physical inconvenience in this
method of telegraphing. The immense Leydon jar formed by the wire, with
its insulating covering,and its protecting envelope of metal,charges itself with
a very considerable quantity of electricity, which passes out through the
receiving instrument during a time relatively long after the contact of the
battery with the wire has ceased. This return current duo to this electric
charge, which increases proportionally to the length of the cable, retards the
transmission of signals,and that to an enormous extent,when the length of
the submerged wire is very great. My experiments have shown that this
electric charge of a wire occupying the centre of a submarine cable is at least
twelve times as great as that of a similar wire insulated in the atmosphere.
If there is added to this that the leakage is inversely proportioned to the
length of the wire it will easily be understood how it is that the injurious
effects of condensation increase with so much rapidity as the length of the
cable becomes greater.
In the method actually put in practice the exterior protecting envelope
of the cable receives, by induction, a charge of electricity equal and con-
trary in sign to that which the battery communicates to the wire, so that
these two quantities of electricity are capable of being held captive the one by
the other, when one is insulated, if a small quantity of free electricity is
neglected. This is exemplified by the well-known experiment of the slow
discharge of the Leydon jar. In my system I am able to shelter the con-
ducting wire from the influence of the exterior conducting envelope, by placing
round this wire au insulating conducting tube, to which I give an electric
charge of a contrary sign to that of the wire, so as to absorb the inductive
action of the interior wire. The charge of this last being able to be regulated
at pleasure,as it is insulated, it follows that the operator can, when he wishes
it, stop the discharge of the submariue conductor. In my cable there is first
around the conducting wire a coating of gutta percha or other insulating

page_text: inaterial, then a conducting envelope composed of a wire coiled around the
gutta percha; over this conducting tube is another insulating coating of gutta
percha,and,lastly, the exterior protecting envelope, which will be arranged as
in cables now in use. The conducting tube should be continuous; to form it
I take a ribbon of copper, that is to say, a copper wire flattened by rollers.
This ribbon is arranged in close coils, and the different coils are united by a
layer of copper,deposited by the electrotype process. To avoid the chances
of breakage,it is formed of several layers of wire, superposed the one on the
other,and coiled in contrary directions. Each layer is itself formed of several
metallic wires, coiled on at the same time, as is done in producing the pro-
tective envelope of cables. The section of this tubular conductor should beat
least equal to that of the interior conducting wire. The cable is worked with
two batteries of equal power, presenting their contrary poles, or it may be by
means of a single battery, the transmitter being so arranged that it can make
the same contacts as two separate batteries,an arrangement easily inade,as
herein-after shown.
A preliminary operation precedes the transmission of a dispatch, so as to
arrange the cable to work by means of a slight excess of positive electricity.
I proceed as follows:-I make the contact of the pole of the battery M, N,
Fig. 1, with the conductor C, C, D, DI, for a sufficient time, which will
never exceed a few seconds, even for cabies of a very great length, the
conducting wire A, B, communicating at A with the earth. The conductor
C, C, D, D¹, then charges itself with negative electricity, and produces two
negative condensationsu poneachofits faces, internalandexternal; the electricity
of the internal face draws to the conductor A,B,an equal quantity of positive
electricity arising from the decomposition of the neuter electricity of the wire
and of the earth. The external face exerts a similar influence upon the
external envelope. The dotted lines g, B, h, B, represent the decreasing
series (according to Olim's law) of tensions with positive condensation, and
a, D, b, D, a', D', 6', D, the series of negative tensions of the insulated
tubular conductor; e, E,aud e', F', the external positive tensions, the quantities
of electricity of contrary signs being equal two and two, within a small
fraction. During this preliminary operation the receiver R is traversed by a
positive current going from B to A, but no notice is taken of the passage of
this current. The positive current directed from B to A stops when the
condensation is produced and the negative current is able to continue to
pass from C, C³, to D,D',without affecting the receiver; after this contact of
the negative pole of the battery M,N,and of the tubular conducting envelope
C,C,D, D'; the cable is prepared to produce the signal. The contact of the

page_text: negative pole of the battery M, N. is then broken, and at the same time the
communication of the extremity A of the conducting wire with the positive
pole G, H, is established. The receiver moves under the influence of the
positive current coming from two sources, first, from the discharge of the wire
A, B, which is the immediate consequence of the suppression of the negative
current at C; second, from the positive current of the pole G, H. 'The
first source is less abundant than the second. It is in fact easy to see that
from the moment when the positive pole of the battery G, H, touches the end
A of the conducting wire, the negative electricity of the internal face of the
tubular conductor C, C, D, D', is retained by the positive tension developed
upon the conducting wire A, B, and that there is disengaged to assist
in the production of the signal only a small excess of positive electricity
corresponding to the small quantity of free electricity, which is disengaged
from the internal face of the tubular conductor. Now, it is also evident
that the battery G, H, not having to perform the preliminary work of con-
densation, the conducting wire A, B, as respects the transmission of the
current, will be found in conditions very similar to that of a wire suspended in
the air; the signal will therefore be produced rapidly, without the rotardation
due to electric condensation. This first advantagens respects the transmission of
the electric current is not the most important. We will now examine how the
interruption of the current is to be produced. First, the contact of the positive
pole of the battery G, H, at A is broken; second, the contact of the negative
pole of the battery M, N, at C is re-established. The utility of breaking the
contact with the positive pole at A is evident, but the establishing the contact
at C gives rise to several results, which it will be useful to examine in
detail. While the contact has been made at A and broken at C for the
transmission of a current, the gutta percha not insulating perfectly a small
portion of the negative charge b, D, b', D', of the internal face of the tubular
conductor, has penetrated the coating of gutta percha,and has formed neutral
electricity with the positive charge of the conductor A, B, besides a small
excess of free negative electricity has passed out into the earth; the negative
tensions b, D, 61, 1)', are thus diminished by a small quantity. Also during
this same transmission, the tensions a, D, a', D, e, F, e, F', have been able to
escape freely into the earth, the two first by the earth wire D, T, the
others directly into the waters of the sea, for they are as is herein-after shown
independent of the action of the battery G, H. These tensions have then
cousiderably diminished. Let us admit what appears to me to be exaggerated,
that during the transmission that they may have lost or even of the
electricity which they held. When then the contact with the positive pole is

page_text: broken at A, and the negative pole connected at C, the battery M, N,
accomplishes the double work of reparation; it re' urns to the internal face of
the tubular conductor the small quantity of negative electricity which it has
lost, then it re-establishes the normal state of the tensions a, D, a', D', e, F,
el, F; it is then clear that the positive charge of the wire A, B, cannot flow
out by the receiver R, or at least that there flows out after the breaking of
the contact with the positive pole at A only a small excess of positive tension
similar to the quantity of electricity which the wire A, B, would contain if
it was insulated in the atmosphere. According to my experiments this
quantity will be even smaller. The tensions and the condensations have now
become again that which they were after the preliminary operations, and to
return to this state a much shorter time has been necessary than even for
that operation, because the battery M, N, has to do at this time only
at most the or the of the work which it accomplished in the first
place. In short to transmit signals it is necessary only to make alternately
the contact of the battery M, N, at C, and the communication with the earth
at A, then to interrupt it at C, and to make the contact of the positive pole
at A. The first movement of the receiver R is not counted; after this, each
signal is produced by making contactat A, then breaking contact at C to prevent
the discharge of the wire A, B, or to stop it suddenly if it had already
commenced. This last contact of the pole M, N. has then the advantage of
hindering the discharge of the wire, without the current which traverses
the tubular envelope being able to work the instrument. By this system
the inconvenience of charging and discharging successively for each signal
the condensor represented by the cable is avoided in the interval between two
signals, the condensed positive electricity is maintained by the negative tension
developed upon the tubular conductor, and on a fresh contact of the positive
pole and of the conducting wire, the propagation of the current, no longer
meeting with any obstacle from the condensation which is already produced, is
accomplished with rapidity.
The employment of the telegraphic system of Professor David Hughes
will, for my cable, present a very great advantage. In Hughes's apparatus a
single emission of a current suffices for the transmission of a letter; all the
currents have also sensibly the same duration. In this case it will be necessary
to make the following improvement in the working of the cable :—
•
A battery, of which the positive pole is in contact with the earth, and of
which the number of the elements is suitably arranged, presents its negative
Pole to the extremity of the conducting tube near the receiving instrument
The armature, which in this system is released by the electro-magnet of the

page_text: receiver at the time of the passage of a current,carries a wire coming from this
tubular conductor. When the armature moves away from the electro-magnet,
this last, by means of the metallic wire, puts the conducting tube in contact
with the negative pole of the battery; besides, the person who transmits the
despatch has. after the production of the signal, separated the wire from the
positive pole of the battery which transmits the signal, and connected the con-
ducting tube with the negative pole; this last then becomes negatively
charged from its two ends, and the current which transmits the signal is
arrested more rapidly.
However, there results from this arrangement an inconvenience, which is,
that the conducting tube has too strong a negative charge for the transmission
of the signal which follows. The interval of time which separates two signals
may be employed to allow the excess of negative electricity to escape from the
conductor, by arranging an earth wire in the neighbourhood of the armature
so as to put the tube in communication with the earth, so as to discharge it
during the interval of time. It should be well understood that this communi.
cation with the earth should be imperfect and suitably regulated.
The transmitter will be constructed on the following principles:-An insu-
lated bar p, q, Figure 2. moveable around the point o is arranged, so as to be
able to take the positions p, q, r, s, and to touch alternately with its end p the
conductors A and C, and with its end g the earth wires h and k. Each of its
faces will carry at each end a metallic blade. At pand q, on the right side,
two blades communicate with the positive pole; on the left side and at the
same level two blades communicate with the negative pole of the same bat-
tery. In the position p, q, the positive pole will touch the conductor A, and
the negative pole the earth wire T. In the position 2, s, the negative pole will
touch the conductor C, and the positive pole the earth wire T. For the pre-
liminary operation an earth wire W will touch the wire A, while the negative
pole will be in communication with C.
If experiments made with very long cables should show that it is advisable
to employ batteries of different intensities to make the successive contacts at A
and C, it will be necessary to employ a different transmitter, of which the
arrangement is so simple it is not necessary to describe it. The receiver
also which will be employed will be that which is most suitable for each
particular case.
In the arrangement which I have designed I do not endeavour to prevent
induction; on the contrary, I maintain the condensed electric charge at its
maximum, and I make it serve for the transmission of the signal.
That which constitutes the essential base of my Invention is, the employ-

page_text: ment of a continuous tube enveloping the conducting wire, and separated from
by a layer of insulating material,into which I transmit a currentofacontrary
sign to that of the interior wire,so as to prevent this last from dischargingitself,
and thus to stop suddenly the current which traverses the receiver. I employ
for the production of the signal aslight excess of free electricity, arising partly
from the disconnection of the negative pole of the battery M, N, at C, and
partly from the contact of the positive pole of the battery G,H,at A. By reducing
in this manner to a considerable extent the work which the battery has to do
for each signal, I obtain in the same time the transmission of a greater number
of signals,in place of producing for each signal, as is done at present, the com-
plete charging and discharging of the submarine cable.
My cable has the advantage of transmitting in a given time a greater
number of despatches,and that with greater certainty,than the cables nowem-
ployed. Thus it will be possible to employ very long submarine lines without
condensation, rendoring transmission impossible.
In witness whereof,I,the said Claude Marie Guillemin, have hereunto set
my hand and seal, this Twelfth day of November, in the year of our
Lord One thousand eight hundred and sixty.
T. BASSET.
CLAUDE MARIE GUILLEMIN. (L.s.)