AN IMPROVED PROTECTIVE AND INSU- LATING COVERING FOR TELEGRAPHIC CONDUCTING WIRES AND COMPOUND دو FOR FORMING THE SAME
Year: 1871

page_text: LETTERS PATENT to Austin Goodyear Day, of Seymour, Connecticut,
United States of America, now of No. 8, Southampton Buildings,
London, for the Invention of "AN IMPROVED PROTECTIVE AND INSU-
LATING COVERING FOR TELEGRAPHIC CONDUCTING WIRES AND COMPOUND
دو
FOR FORMING THE SAME."
Sealed the 12th September 1871, and dated the 20th May 1871.
PROVISIONAL SPECIFICATION left by the said Austin Goodyear Day
at the Office of the Commissioners of Patents, with his Petition,
on the 20th May 1871.
I, AUSTIN GOODYEAR DAY, of Seymour, Connecticut, United States
of America, now of No. 8, Southampton Buildings, London, do hereby
declare the nature of the said Invention for "AN IMPROVED PROTECTIVE
AND INSULATING COVERING FOR TELEGRAPHIC CONDUCTING WIRES AND COMPOUND
FOR FORMING THE SAME," to be as follows:-
This Invention relates to telegraphic conductors, consisting of a
central metallic conductor or wire surrounded by an insulating and pro-
tective covering. It also relates to a new compound for forming the
said covering.

page_text: It is well known that wire for telegraphic and other purposes covered
with various materials or compounds (especially compounds of india-
rubber and gutta percha) has already been extensively used, but the
coverings formed by these substances have all been found more or less
imperfect. A perfect covering for a telegraphic wire conductor must
possess many properties, the absence of any one of which will greatly
impair its usefulness.
It is not necessary to enumerate all of the
requirements for such a covering, but the following are the most impor-
tant-It must be a good non-conductor of electricity; it must possess
great plasticity and ductility, so that it may be easily applied to the
wire; it must be very flexible or pliable, and at the same time very
cohesive and adhesive, so that it will bend or twist with the wire
without opening, or separating, or becoming detached therefrom; it
must remain unaffected by changes of temperature, so that there shall
be no displacement of the wire from its centre; it must be without
liability to such molecular changes as will destroy its insulating and
protective properties; and it must be capable of resisting atmospheric
influences and also the destructive chemical and vital agencies to which
it will be exposed when sunk in ocean waters or buried in the ground.
Although some of the materials for covering the conducting wires
heretofore used may possess one or several of the properties necessary for
the insulation and protection of telegraphic conductors under favourable
circumstances, yet all of them have been found on trial to be deficient in
some respects, and therefore much trouble is continually experienced in
connection with the maintenance of the conductors; but by the peculiar
combination of materials herein-after specified, which I have discovered
after many experiments and much thought and labour, I have pro-
duced an improved insulating and protective compound whereby I am
enabled to furnish telegraphic conductors which possess all of the above
enumerated and other required properties, and I have thus accomplished
the object heretofore unsuccessfully sought to be accomplished by the
employment of other means.
My improved protective or insulating compound is formed by the
combination of india-rubber or caoutchouc and a small quantity of other
substances herein-after specified combined with the artificial substance or

page_text: are combined in about the following proportions, viz. :-Caoutchouc
twenty pounds, the aforesaid artificial compound twenty to twenty-five
pounds, and sulphur two and a half pounds. To these substances
prefer to add three pounds of litharge or other oxide of lead or carbonate
of lead which although not essential to the compound yet improves it in
certain respects as herein-after specified. The compound having these
substances thus combined is then ready for application to the wire.
Although the above proportions are such as will give satisfactory
results yet they may be varied to impart to the compound more or less
of the particular property due to either or any of the ingredients of which
it is composed. The caoutchouc imparts strength and cohesiveness to
the compound. Gutta percha might be used as a partial substitute for
the caoutchouc but the latter alone is far preferable. The compound
as before stated may be made without the litharge (or oxide or carbonate
of lead) but this material accelerates the vulcanization during the process
of covering the wire with the compound.
The compound is applied to the wire to be covered in a soft condition
by passing it with the said wire through a suitable die, the diameter of
whose aperture will depend upon the diameter of the wire and thickness
of the protective covering. The compound thus applied to the wire is
then vulcanized by the application of heat either by steam or otherwise.
My improved compound consisting of the above specified ingredients
although intended to be used chiefly for the covering of telegraph wires
may be employed as a substitute for india-rubber or gutta percha for
many purposes, and the proportion of the india-rubber and the aforesaid
artificial substance which forms part of this improved compound may be
varied to any required extent.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Austin Goodyear Day, in the Great Seal Patent
Office on the 12th October 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, AUSTIN
GOODYEAR DAY, of Seymour, Connecticut, United States of America,
now of No. 8, Southampton Buildings, London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twentieth day of May, in the year of

page_text: our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Austin Goodyear Day, Her special licence
that I, the said Austin Goodyear Day, my executors, administrators,
and assigns, or such others as I, the said Austin Goodyear Day, 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 "AN IMPROVED
PROTECTIVE AND INSULATING COVERING FOR TELEGRAPHIC CONDUCTING WIRES ANd
COMPOUND FOR FORMING THE SAME," upon the condition (amongst others)
that I, the said Austin Goodyear Day, my executors or administrators,
by an instrument in writing under 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 same 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 Austin Goodyear Day, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement:-
This Invention relates to telegraphic conductors consisting of a central
metallic core or wire surrounded by an insulating and protective covering,
and to a new compound for forming the said covering.
It is well known that wire for telegraphic and other purposes covered
with various materials or compounds (especially compounds of india-
rubber and gutta percha) has already been extensively used, but the
coverings formed by these substances have all been found more or less
imperfect. An efficient covering for the wire of a telegraphic conductor
must possess many properties, the absence of any one of which will
greatly impair its usefulness. It is not necessary to enumerate all of
the requirements for such a covering, but the following are among the
most important:-It must be a good non-conductor of electricity; it
must possess great plasticity and ductility so as to be easily applied to
the wire; it must be very flexible or pliable, and at the same time very
cohesive and adhesive so that it will bend or twist with the wire without

page_text: opening or separating or becoming detached therefrom; it must remain
unaffected by changes of temperature so that there shall be no displace-
ment of the wire from its centre; it must be without liability to such
molecular changes as will destroy, its insulating and protective properties,
and must be capable of resisting atmospheric influences, and also the
destructive chemical and vital agencies to which it will be exposed when
sunk in ocean waters or buried in the earth.
.
Although some of the materials heretofore used for covering tele-
graphic conducting wires may possess one or several of the properties
necessary for their insulation and protection under favourable circum-
stances, yet all of them have been found on trial to be deficient in some
respects, and therefore much trouble is continually experienced in
connection with their maintenance. But by the peculiar combination
of materials herein-after specified, which I have discovered after many
experiments and much study and labor, I have produced an improved
insulating and protective compound whereby I am enabled to furnish
telegraphic conductors which possess all of the above enumerated and
other required properties, and I have thus accomplished an object hereto-
fore unsuccessfully sought to be accomplished by the employment of
other means.
My improved protective, or insulating compound is formed by the
combination of india-rubber or caoutchouc and a small quantity of other
substances herein-after specified with the artificial elastic substance or
compound described in the Specification of an Invention for which I
have obtained Letters Patent bearing date the Fifteenth day of April,
A.D. 1871, No. 1010. These ingredients are combined in about the
following proportions, viz., caoutchouc, twenty pounds; the aforesaid
elastic compound twenty to twenty-five pounds, and sulphur two and
a half pounds. To these substances I prefer to add three pounds of
litharge or other oxide of lead or carbonate of lead which although not
essential yet improves the said insulating compound in certain respects,
as herein-after specified. The compound consisting of these substances
thus combined is then ready for application to the wire.
Although the above proportions are such as will give satisfactory
results yet they may be varied to impart to the compound more or less
of the particular property due to either or any of the ingredients of
which it is composed. The caoutchouc imparts strength and cohesiveness
to the compound, gutta percha or a mixture of the same and caoutchouc

page_text: might be used as a substitute for the caoutchouc to some extent, but
the latter alone is preferable in every respect. The compound, as before
stated may be made without the litharge (or oxide or carbonate of lead),
but this material accelerates the vulcanization during the process of
covering the wire with the compound.
The compound is applied to the wire to be covered in a soft condition
by passing it with the said wire through a suitable die, the diameter of
whose aperture will depend upon the diameter of the wire and thickness
of the protective covering. The compound when applied to the wire is
vulcanized by subjecting it to a suitable heat by steam or otherwise.
My improved compound consisting of the above specified ingredients
although intended to be used chiefly for the covering of telegraph wires,
may be employed as a substitute for india-rubber or gutta percha for
many purposes, the proportion of the india-rubber to the aforesaid
elastic compound which forms part of this improved compound being
varied to any required extent.
Having thus fully described my said Invention and shewn how tho
samo may be conveniently and advantageously carried into practice I
claim,-
-
First. A telegraphic conductor with a protective and insulating
covering made and applied as herein specified.
Second. The compound for forming the said covering and for other
similar purposes consisting of india-rubber or caoutchouc and the other
substances specified combined together in the manner and proportions
set forth.
In witness whereof, I, the said Austin Goodyear Day, have here-
unto set my hand and seal, this Fifth day of August, in
the year of our Lord One thousand eight hundred and seventy-
one.
Witness,
W. J. LOWE.
AUSTIN G. DAY. (L.S.)