A NEW OR IMPROVED SYSTEM OF CABLES OR OTHER CONDUCTORS DESIGNED TO SUPPRESS TELEGRAPHIC AND TELEPHONIC INDUCTION
Year: 1885

page_text: ILL ELE
I, RENÉ TAMINE, of Mons, in the Kingdom of Belgium, Civil Engineer, do
hereby declare the nature of my said invention for "A NEW OR IMPROVED
SYSTEM OF CABLES OR OTHER CONDUCTORS DESIGNED TO SUPPRESS TELEGRAPHIC
AND TELEPHONIC INDUCTION" and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following statement:-
If we consider a series of parallel telegraphic or telephonic lines A, B, C, D,
E F, G, H (Figure 1) we know that a communication transmitted upon any one
of such lines, E F, for instance, can be seized by all the others, in consequence of
the induction phenomenon. Experience shews that the longer the lines are, the
stronger is the induction.
Great many electricians have attempted to suppress this induction which is the
worst enemy of telegraphy and telephony. No combination hitherto discovered
bas achieved any satisfactory results.
In my opinion, it is not by arranging certain combinations of apparatuses, more
or less ingenious, either at the receptor, or transmitter, or at any particular point
of the line, that one can arrive at the solution of the problem. Those who took
that course forgot that the induction arises on the whole length of the lines, where
the latter are set opposite each other.
I will now explain my view in regard to the induction by means of a very
simple comparison:-Just as in bydraulic, no current of water can be established,
between two points A and B Figure 2 only when a difference of level exists
between these points, so also in electricity, a current can only arise if a difference
of electric levels exists, such levels constituting what is termed in modern
phraseology "potentials." The induction may in my opinion be compared to an
infinite number of little streams, very close to each other which discharge their
waters into a canal A. B (Figure 3) establishing a current towards the extremity B,
this would therefore necessitate a higher pressure towards A.
Let us ask ourselves how to prevent receiving, in B, the current directed
towards A to B. There are 3 ways which immediately present themselves to the
mind-1st To establish, as per ab an embankment high enough to prevent the
waters from reaching the canal A. B.-2nd To construct, immediately up-stream
of B, a weir, o d intended to keep the waters within the canal-3rd To contrive in

page_text: such a way as to furnish a current of water directed in a contrary direction to the
first and equal to the latter. By this means the level in A. B will rise to the same
extent at all the points of the canal, and there will evidently not be a current
towards B if we suppose the limit points A. B situate at a like level.
Let us apply these various cases to electricity: suppose (Figure 4) 2 parallel
lines A. B. and C. D. upon the line A. B, a current is started in the direction of
the arrow.
In availing ourselves of the comparison above set out, the electric
streams escaping from A. B come and establish an inducted current in C. D. The
problem to be solved consists in finding the means of not receiving in D, a current
CD.
The first means which we examined above would consist in embanking the wire
of the line C, D, that is to say to surround it in such a way to prevent the
induction arriving at the line. I have tried for this purpose many bodies, solid,
liquid and gaseous, and have not found one to suit me.
The second means would have the effect of cutting the circuit a little beyond D;
but such an arrangement would have the disadvantage that it would no longer be
possible to transmit a main current from C to D and thus render it impossible to
communicate upon the line C. D.
These two systems cannot therefore be available to solve the problem now
before us.
The only means left us is the third, and we will see in the course of this
statement how I arrive at solving the problem in question, in starting from a
principle which may be assimilated to this third means.
The system of cables and apparatuses which I claim as my invention rests upon
the following principle to which my experiments have led me.
Suppose A to be a' coil forming electro-magnet: an insulated brass wire is wound,
in a certain direction, round a wooden core or one of card board, iron or any other
substance whatsoever. One of the ends of the wire meets one of the poles of the
pile B. The other end of the wire C is unconnected (Figure 5). Beside the coil A,
1 place a second coil D analogous to that I have just described. Suppose that the
wire round the coil D to be wound in the same direction as round the coil A.
When I touch the second pole of the pile B with the unconnected end b, I send
an electric current into A. Now the circuit apertures and closures, or the variations
of the current produce an induction in the neighbour coil D. If in the circuit of D,
in E, for instance, one introduces a receiving ear-trumpet such as used in telephony,
one hears very distinctly sounds or noises corresponding to those which one would
hear by placing a second ear-trumpet in F of the main circuit.
Admit now that I roll round D another insulated brass wire in a contrary
direction to the first. Taken by itself, it acts the same as the first namely it also
lets sounds be heard in a receiving ear-trumpet introduced in E.
But when one unites the unconnected ends of these 2 wires wound round in a
contrary direction, both entering together and going out together, nothing whatever
is heard in an ear-trumpet placed for instance in E-It must therefore be admitted
that one of the effects is neutralized by the other.
Going upon this principle, we have imagined the means of suppressing telegraphic
or telephonic induction in a series of lines sufficiently close to each other. I con-
stitute my lines by means of a central core, formed of a wire of iron or steel, or of
a cord, or any other substance whatsoever. Round the core, I wind in a contrary
direction two conducting wires well insulated; I unite the opposite ends, those
entering together and those going out together, and I thus obtain a cable which
prevents the hearing of conversations, sounds, and noises, resulting, from the
induction phenomenon from line to line. Such a cable can perfectly be employed
for transmitting the main current and such conversations as one would wish to
hold respectively upon each of these very lines.
Independently of this arrangement, I reserve to myself the use, on-a. great
number of lines, of one single cable constituted as follows: upon any kind of core,
I first wind round two insulated conductors in a contrary direction, this is a first

page_text: line. Round this line, I again wind two insulated conductors in a contrary
direction, this is a second line-Round this second, I constitute a third similar
one, then a fourth and so on, according to the number of lines required.-The
convolutions may be as close to or distant from each other as I wish, and, finally,
I can, if I think fit, enclose the whole in a leaden tube or one of other substance.
When I use as the interior core, a wire, or any kind of conducting wire, I make
that core act as a conducting line, if I wish to do so, or I insulate same, or even
suppress same, after the windings.
Such are the systems which enable the solution of that very important question
viz. the suppression of the telegraphic or telephonic induction, produced from line
to line.
If one desires, instead of two wires wound in a contrary direction, only to use
one single wire, it would be necessary for a certain length, to wind it in one
direction; after that, for an equal length, wind it in a contrary direction, and
repeat this operation for the whole length of the wire.
My invention may be recapitulated as follows: Nullification of the induction by
means of compensating wires or cables.
I reserve to myself employing wires in the shape of a ribbon or cylinder or
assuming any geometrical shape whatsoever. These wires may be rolled, 1, 2, 3, or .
a greater number at once, as shewn in Figure 6 for 3 lines, it is obvious that round
these three wires I wind a like number in a contrary direction.
When considering each of my lines separately, one may start the current of
communication upon either one of the two wires the second wire would connect
the first immediately prior to entering the receiving trumpet Figure 7, in other
words, the current would only pass through the transmitting apparatus, as set out
in Figure 7, L being the line and N the induction coil.
Having now particularly described and ascertained the nature of ny said
invention, and in what manner the same is to be performed, I declare that what
I claim is
The system of telegraphic and telephonic lines formed of two wires rolled in
contrary direction round a core which may disappear after the winding.
T
2011 1
WM P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, and
323, High Holborn, London,
Filing Agents for the Applicant.