A NEW SYSTEM OF, AND INDUCTION CURRENT GENERATOR FOR, LONG CABLE TELEGRAPHY
Year: 1885

page_text: I SECONDO Roos of 15 Arundel Street Haymarket in the County of Middlesex
Electrician do hereby declare the nature of my said invention for "A NEW
SYSTEM OF, AND INDUCTION CURRENT GENERATOR FOR, LONG CABLE TELEGRAPHY "
to be as follows:-
This Invention consists in a new system of induction current generator for
telegraphic purposes and particularly for long cable telegraphy.
The generator is constructed in the form of a cable of indefinite length in the
following manner. A core composed of a suitable number of parallel straight iron
wires is covered with a tape, the covering being then varnished and paraffined.
Upon this core is wound a close spiral formed of a coarse covered copper-wire which
constitutes the primary wire of the generator. This wire is paraffined and covered
with a tape which is then varnished and paraffined. Upon this is wound a close
spiral of fine covered copper wire which constitutes the secondary wire. This is
also paraffined and in order to protect it the whole is served with a tape which
is afterwards varnished. The secondary wire may be divided into a greater or less
number of sections of which the beginnings and ends emerge from the cable in the
form of flexible conductors. The cable thus formed is wound upon a bobbin which
may for convenience be formed by the condenser itself. The two ends of the
primary wire communicate with the generator of the inducing current, with the
condenser and the make and break. The commencements and ends of the various
sections of the secondary wire communicate respectively with two series of studs
in such way that the several sections may be readily connected in tension or
quantity at will, and in various possible combinations according to the purpose in
view. In employing this generator for long cable telegraphy I may use the Morse
key for transmitting, and receive the signals directly by a telephone as by a Morse
sounder.

page_text: SECONDO Roos 15 Arundel Street Haymarket in the County of Middlesex do
hereby declare the nature of my invention for A NEW SYSTEM OF, AND INDUCTION
CURRENT GENERATOR FOR, LONG CABLE TELEGRAPHY and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement:-
This Invention consists in a new system of induction current generator for
telegraphic purposes and particularly for long submarine and subterranean lines,
and in its combination with other apparatus as hereinafter described.
The generator is constructed in the form of a cable of indeterminate length
composed essentially of a core of iron wires, a single close spiral of coarse covered
insulated copper wire (constituting the primary wire of the generator) wound upon
the core, a close spiral of fine covered insulated copper wire wound upon the first
spiral and constituting the secondary wire, the several elements above referred to
being separated by intervening spirally wound layers of tape which are varnished
and paraffined. The cable thus formed may be wound upon a bobbin which may
for convenience be formed by the condenser itself. In applying the generator to
long distance telegraphy the ends of the primary or local circuit of the generator
are connected with a condenser and with the poles of a battery, a Morse key or
other transmitter and a make and break being interposed in the circuit. One end
of the secondary or line circuit is to earth and the other to the submarine cable or
subterranean wire whose other extremity is to earth after passing through the
receiver. The receiver is a telephonic receiver employed either directly as
"sounder " or applied to act as a relay to actuate a telegraphic printing
instrument.
a
In the accompanying drawings figure 1 illustrates in an elementary way the
method of applying this invention to long distance telegraphy. Figure 2 shows a
short piece of the cable generator the extremity being partly unwound to show its
construction.
a, is the bundle of iron wires say seven in number each of one millimetre in
diameter laid parallel side by side so as to form a continuous core extending the
whole length of the cable generator. b, is a tape wound spirally thereon in
the usual manner and afterwards coated with shellac varnish and paraffined in the
known way.
c, is the primary wire closely wound in one layer upon the core
covered as above described. This primary coil is a cotton covered copper wire of
say one millimetre in diameter. After being wound on the core it is paraffined and
then covered with a tape d, which after being wound thereon is varnished and
paraffined. e is the secondary coil being a closely wound single coil or layer of
.fine silk covered copper wire of 14 hundredths of a millimetre in diameter. It is
wound in the same direction as the primary wire and is also paraffined after being
wound and is then covered by a tape f. which is afterwards varnished.
For a telegraphic cable of say, 2,400 miles in length, the generator-cable con-
structed as above described would be about 400 feet in length but I would have it

page_text: understood that I in no way limit myself to the proportions or to the number of
coils above specified for the wires of the cable generator, those given being merely
those which I have found to give good results; they may be varied according to
the end to be accomplished.
For long cable telegraphy the cable generator having but a single coil or layer
for the primary and secondary wires respectively, is the best, as, besides avoiding
self-induction of the wire, this arrangement enables the longest cable to be traversed
by the weakest currents. The cable generator is, for the sake of convenience,
coiled upon a suitable reel within which the condenser may be contained, the
cable being protected by a casing and its ends connected up as herein before
described.
Having described the practical construction of my generator I would observe in
explanation of the novel effects obtained thereby, that in the ordinary induction
coil the induced current is produced principally by the action of the strong mag-
netization of the soft iron core of the electro magnet, upon a relatively limited
number of coils of the secondary circuit, the action being variable according to the
position occupied by the coils of wire; whereas in the cable generator of this
invention the magnetisation is very feeble but acts always to the same extent upon
an unlimited number of coils of the secondary wire the result being that the induction
currents produced by this new generator differ essentially from those produced by an
ordinary induction coil.
These currents are eminently adapted for telegraphy through long cables as,
owing to their special character, they suffer no retardation by the electro-statical
capacity of the cable, and are able to overcome any resistance (as would a battery
of an immense number of elements having an infinitely small electro-motive force
and coupled in tension) but without the currents attaining such energy as to injure
the cable.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is
1st The generator herein described, consisting of a core of iron wires wound with
a single layer of insulated copper wire forming the primary circuit, upon which
layer is in turn wound a single layer of insulated copper wire forming the secondary
circuit, the whole being combined in the form of a cable substantially as herein
specified.
2nd The combination of the generator of induced electrical currents hereinbefore
described, with a telegraphic transmitter, a make and break (or interruptor of the
current traversing the primary circuit of the generator) a submarine or subterranean
telegraphic cable or wire, and a telephonic receiver employed either as a sounder
or as a relay, substantially as specified.
3rd The combination of the generator of induced electrical currents hereinbefore
described, with a suitable transmitter, with any means of modifying the current of
the primary circuit, with a submarine or subterranean conducting cable or wire, and
with a telephone receiver employed as a sounder or as a relay.
Dated this 4th day of May 1885.
SECONDO ROOS.
By his Agents, A. M. & Wm Clark,
53, Chancery Lane, London, W.C.