AN IMPROVED PREPARATION OR COMPOUND APPLICABLE POR INSULATING ELECTRIC CONDUCTORS AND FOR SUCH PURPOSES AS INDIA-RUBBER AND OTHER VULCANIZABLE GUMS ARE APPLICABLE
Year: 1868

page_text: LETTERS PATENT to William Perkins, of Russell Place, Fitzroy
Square, in the County of Middlesex, Chemist, and George
Grainger Tandy, of Anerly Road, in the Hamlet of Penge, in
the County of Surrey, Gentleman, for the Invention of "AN
IMPROVED PREPARATION OR COMPOUND APPLICABLE POR INSULATING ELECTRIC
CONDUCTORS AND FOR SUCH PURPOSES AS INDIA-RUBBER AND OTHER
VULCANIZABLE GUMS ARE APPLICABLE."
Sealed the 14th August 1868, and dated the 18th February 1868.
PROVISIONAL SPECIFICATION left by the said William Perkins
and George Grainger Tandy at the Office of the. Commissioners
of Patents, with their Petition, on the 18th February 1868.
We, WILLIAM PERKINS, of Russell Place, Fitzroy Square, in the
County of Middlesex, Chemist, and GEORGE GRAINGER TANDY, of
Anerly Road, in the Hamlet of Penge, in the County of Surrey,
Gentleman, do hereby declare the nature of the said Invention for
"AN IMPROVED PREPARATION OR COMPOUND APPLICABLE FOR INSULATING ELECTRIC
CONDUCTORS AND FOR SUCH PURPOSES AS INDIA-RUBBER AND OTHER VULCANIZABLE
GUMS ARE APPLICABLE," to be as follows:-
This Invention has for its object the production of a preparation
or compound which is applicable for coating or covering telegraphic

page_text: cables or electric conductors, and for such other purposes as india-
rubber, gutta percha, gum balata, and other vulcanizable substances
are applicable.
The Invention consists in combining with india-rubber, gutta percha,
or other analogous gums or substances, together with the sulphur and
solvents usually employed in treating these substances, anthracene
or para-naphthaline and naphthaline, which are hydrocarbons obtained
from the distillation of coal tar. These latter substances may be
added to the rubber or other gum in any desired proportion varying
from 25 to 75 per cent. according to the degree of hardness or
toughness required; and they may be combined with the gum at the
same time as the sulphur and by means of the ordinary apparatus
used for the purpose, or the sulphur may be first mixed with the
rubber and then the anthracene and naphthaline added by masticating
or squeezing between rollers.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Perkins and George Grainger Tandy
in the Great Seal Patent Office on the 17th August 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, WILLIAM
PERKINS, of Russell Place, Fitzroy Square, in the County of Middlesex,
Chemist, and GEORGE GRAINGER TANDY, of Anerley Road, in the
Hamlet of Penge, in the County of Surrey, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of February, in the
year of our Lord One thousand eight hundred and sixty-eight, in
the thirty-first year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto us, the said William Perkins and George
Grainger Tandy, Her special licence that we, the said William Perkins
and George Grainger Tandy, our executors, administrators, and assigns
or such other as we, the said William Perkins and George Grainger
Tandy, our executors, administrators, and assigns, should at any time
agree with, and no others, from time to time, and at all times there-
after 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

page_text: for "AN IMPROVED PRÉPARATION OR COMPOUND APPLICABLE FOR INSULATING
ELECTRIC CONDUCTORS AND FOR SUCH PURPOSES AS INDIA-RUBBER AND OTHER
VULCANIZABLE GUMS ARE APPLICABLE," upon the condition (amongst others)
that we, the said William Perkins and George Grainger Tandy, our
executors or administrators, by an instrument in writing under our, 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 George Grainger Tandy, on behalf
of myself, and of the said William Perkins, do hereby declare the
nature of our said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement (that is to say)
-
This Invention has for one of its objects the production of an
insulating compound applicable for covering telegraphic cables and
electric conductors. The compound is also applicable for the various
purposes for which india-rubber or gutta percha compounds have been
heretofore employed or for which such substances may be used.
Our improved compound is produced by the combination of anthracene
(or paranaphthaline) and naphthalene and compounds thercof with
vulcanizable substances, such as india-rubber, gutta percha, gum ballata,
and other analogous gums and sulphur. The solid hydrocarbons above
referred to (anthracene and naphthaline) are obtained amongst the last
products derived from the distillation of coal tar, the tar produced in
the London gas works being particularly rich in such hydrocarbons.
In order to mix or combine the above substances with each other any
of the well-known and understood processes for mixing or combining
sulphur with such gums may be employed, but we prefer to make use
of heated rollers for the purpose. The proportions in which these
substances are to be mixed will vary according to the quality of gum
employed, and whether a soft, hard, or tough compound be required.
For instance, in using india-rubber it is found that the qualities of
this substance vary so much that in order to produce one uniform
quality of compound, considerable care must be taken, not only as to
the proportions of the naphthaline or anthracene to be employed, but
also as to the quantity of sulphur to be used in the compound.

page_text: In order to produce an insulating compound for covering telegraph
wires or electric conductors, we find that a combination of fifty parts
by weight of sulphured rubber, gutta percha, gum ballata, or other
vulcanizable gums, with fifty parts of naphthaline or anthracene forms
'an excellent insulator and possesses great advantages over gutta percha
and vulcanite of the ordinary manufacture as porosity in the compound
is obviated. In order to produce our improved compound, we find
it advisable first to combine the sulphur with the rubber by passing
the rubber and sulphur between rollers or by mastication in the
ordinary manner, and then to add to the sulphured rubber the desired
proportion of anthracene and naphthaline, which will be combined
with the other materials by passing them between the rollers as when
mixing the sulphur with the rubber. In some cases, however, we add
the anthracene and naphthaline together with the sulphur to the rubber
or other gum, and we then proceed to incorporate all the ingredients
by means of masticating or grinding rollers, as when incorporating
sulphur alone with the rubber in the ordinary manner. Any of the
known solvents, such as bisulphide of carbon, petroleum spirit or
coal tar naphtha may also be employed in combining the naphthaline
or anthracene with the vulcanizable gums. When the ingredients have
all been properly incorporated and intimately mixed, the mass may
either be rolled out into sheets as in the ordinary manufacture of sheet
rubber, and then cut up into strips of suitable width for winding round
or otherwise covering the wires, or the compound may be made up
into any other form according to the purpose for which it is to be
employed.
In applying the compound to telegraph wires or electric conductors
for the purpose of insulating them, we do not confine ourselves to
any particular method, as it may be put on either in longitudinal strips
or wound helically round the wires, or the insulating compound may be
applied in a plastic state to the electric conductor or cable. After the
wires have been covered the change (or curing) of the compound is to
be effected in any of the ordinary ways, viz., by means of superheated
steam, by hot air, or by heating the covered wires in an oven, all of
which processes are well known. The proportions of naphthaline and
anthracene to be employed may be varied from ten to seventy-five
per cent., and the quantity of sulphur may vary from ten to forty per
cent. according to the hardness or toughness required in the compound.
Our improved compound may be employed for any of the purposes to

page_text: which india-rubber, gutta percha, gum ballata, and other analogous
substances are applicable, such as for producing waterproof fabrics,
elastic hose and tubing, the manufacture of boots and shoes, and various
other purposes too numerous to mention.
Having now described our Invention of "An Improved Preparation or
Compound applicable for Insulating Electric Conductors, and for such
Purposes as India-rubber or other Vulcanizable Gums are applicable," and
having explained the manner of carrying the same into effect, we claim
as our Invention the combination of anthracene or paranaphthaline,
and naphthaline with india-rubber, gutta percha, gum ballata, and
other analogous vulcanizable substances, and sulphur for the purpose
of producing a preparation or compound applicable to the uses or
purposes above mentioned or any analogous purposes.
In witness whereof, I, the said George Grainger Tandy, have
hereunto set my hand and seal, the Seventeenth day of August,
in the year of our Lord One thousand eight hundred and sixty-
eight.
GEORGE GRAINGER TANDY. (L.s.)