IMPROVEMENTS IN SUBMARINE ELECTRIC TELEGRAPH CABLES
Year: 1878

page_text: LETTERS PATENT to Willoughby Smith, of 18, Wharf Road, City Road, in the
County of Middlesex, for the Invention of "IMPROVEMENTS IN SUBMARINE
ELECTRIC TELEGRAPH CABLES."
Sealed the 14th February 1879, and dated the 13th September 1878.
PROVISIONAL SPECIFICATION left by the said Willoughby Smith at the
Office of the Commissioners of Patents on the 13th September 1878.
WILLOUGHBY SMITH, of 18, Wharf Road, City Road, in the County of Middlesex.
" IMPROVEMENTS IN SUBMARINE ELECTRIC TELEGRAPH CABLES."
This Invention has for object to construct submarine cables of light specific
gravity, and which at the same time shall not be liable to have their strength
impaired by long submersion. For this purpose I coat the conductor with one or
more layers of gutta percha or insulating inaterial in the ordinary manner. Around
the core so coated I lay steel or iron wires in long open spirals at equal distances
apart from one another, and at the time of laying on these wires cause them to
embed themselves in the outer coating of insulating material. To facilitate this I
use, as the last previous coating of the central core, a somewhat softer material
than gutta percha, by preference a mixture of gutta percha and shellac, and when
laying on the wires either heat the wires as they are laid on, or else heat the outer
surface of the core just before the wires are laid on to it. Afterwards I coat the
core around which the wires have been laid with further coatings of insulating
material. By this means not only can a sound electric telegraph cable be niade of
light specific gravity, but in addition the steel or iron wires, which give strength to
it, are protected from the action of salt water upon them after the cable has been
Prien 4d)

page_text: submerged. Thus, if by any cause the cable should at any point become injured,
it can readily be raised to be repaired, owing to its lightness and to the fact that
the steel or iron wires which give strength to it are protected, and not liable to
decay.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Willoughby Smith in the Great Seal Patent Office on the 12th
March 1879.
WILLOUGHBY SMITH, of 18, Wharf Road, City Road, in the County of Middlesex.
" IMPROVEMENTS IN SUBMARINE ELECTRIC TELEGRAPH CABLES."
This Invention has for its object to construct submarine cables of light specific
gravity, and which at the same time shall not be liable to have their strength
impaired by long submersion. For this purpose I coat the conductor with one or
more layers of gutta percba or insulating material in the ordinary manner. Around
the core so coated I lay steel or iron wires in long open spirals at equal distances
apart from one another, and at the time of laying on these wires cause them to
embed themselves in the outer coating of insulating material. To facilitate this I
use, as the last previous coating of the central core, a somewhat softer material
than gutta percha, by preference a mixture of gutta percha and shellac, and when
laying on the wires either beat the wires as they are laid on, or else heat the outer
surface of the core just before the wires are laid on to it. Afterwards I coat the
core around which the wires have been laid with further coatings of insulating
material. By this means not only can a sound electric telegraph cable be made of
light specific gravity, but, in addition, the steel or iron wires which give strength
to it are protected from the action of salt water upon them after the cable has been
submerged. Thus, if by any cause the cable should at any point become injured,
it can readily be raised to be repaired, owing to its lightness and to the fact that
the steel or iron wires which give strength to it are protected, and not liable to
decay.
"
In carrying out my Invention I may use for laying the steel or iron wires around
the core a machine of the ordinary "stranding or "twisting" type, with or
without what is known as the "Cordelier" motion, according to the kind of wire to
be embedded, so as either to put a twist on the wires as they are laid on, or put
them on without twist.
"
The " core may be heated by one or more"" Bunsen" burners (although other
suitable arrangements might be used in place of such burners) while passing through
the machine, so as to soften the outer surface only of the core; a second series of
Bunsens are placed so that the wires on passing from the bobbins on the machine
to the "lay plate" or "nozzle "may be heated sufficiently to embed themselves in
the core at the moment of delivery when the "twist" or "lay" is given.
"
"

page_text: In front of the "lay plate" a set of four-grooved rollers standing at right angles
to each other, and arranged so as to press equally on the outer circumference of the
core, closes the grooves made in the core by the hot wire.
The core may also be passed through a heated "compound" previous to the wires
being laid on by the machine, so as to embed the wires in the compound without
beating the core.
By using the same arrangement in front of the machine the wires may receive a
second covering of compound so as to completely cover them.
The above arrangement will answer for any number of embedded wires, or a
complete sheating of the outer surface only.
Having thus described the nature of my Invention, and the manner of performing
the same, I would have it understood that I claim as my improvements in sub-
marine electric telegraph cables the embedding of any desired number of iron or
steel wires in long open spirals in the insulating material by which the conductor is
surrounded, substantially in the manner herein-before described.
In witness whereof, I, the said Willoughby Smith, have hereunto set my hand
and seal, this Twelfth day of March, in the year of our Lord One thousand
eight hundred and seventy-nine.
WILLY. SMITH. (L.S.)