CERTAIN COMPOUNDS AND SUBSTANCES APPLICABLE FOR ELECTRIC " PROVISIONAL SPECIFICATION
Year: 1862

page_text: LETTERS PATENT to Charles Hancock, of West Street, Smithfield, in the
City of London, Manufacturer, and Stephen William Silver, of 4,
Bishopsgate Street, in the said City of London, Manufacturer, for the
Invention of "CERTAIN COMPOUNDS AND SUBSTANCES APPLICABLE FOR ELECTRIC
"
PROVISIONAL SPECIFICATION left by the said Charles Hancock and
Stephen William Silver at the Office of the Commissioners of Patents,
with their Petition, on the 12th December 1862.
We, CHARLES HANCOCK, of West Street, Smithfield, in the City of London,
Manufacturer, and STEPHEN WILLIAM SILVER, of 4, Bishopsgate Street, in the
said City of London, Manufacturer, do hereby declare the nature of the 'said
Invention for "CERTAIN COMPOUNDS AND SUBSTANCES APPLICABLE FOR ELECTRIC
INSULATION, AND OTHER PURPOSES," to be as follows:-
To obviate certain defects of caoutchouc and other substances employed for
electric insulation and other purposes, we combine caoutchouc and other
similar substances, or some of them with a gummy or milky substance such
as or having properties similar to the gum or milk called "ballata." We also
combine caoutchouc with colcothar (oxide of iron) also with ground or pul-
verized vulcanized caoutchouc. We also combine sulphur with caoutchouc
and ballatȧ, and vulcanize the compounds with or without the addition of
shellac and parafine. These compounds are formed by the processes of masti-
cation, rolling, and moulding, or mastication, solution, rolling, and moulding.
Some or all of these compounds and substances are suitable for all insulation
purposes, and also for being made into sheets, belts, hose, tubes, and other
articles, and also for being spread on suitable surfaces.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles Hancock and Stephen William Silver in the Great
Seal Patent Office on the 12th June 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, CHARLES
HANCOCK, of West Street, Smithfield, in the City of London, Manufacturer,
and STEPHEN WILLIAM SILVER, of No. 4, Bishopsgate Street, in the said City
of London, Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of December, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us, the
said Charles Hancock and Stephen William Silver, Her special license, that
we, the said.Charles Hancock and Stephen William Silver, our executors,
administrators, and assigns, or such others as we, the said Charles Hancock
and Stephen William Silver, our 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 of fourteen years 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, in such manner as we might think fit, an Invention for "CERTAIN
COMPOUNDS AND SUBSTANCES APPLICABLE FOR ELECTRIC INSULATION AND OTHER PUR-
POSES," upon the condition (amongst other conditions) that we, the said Charles
Hancock and Stephen William Silver, our executors or administrators, should
particularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, by an instrument in writing
under our hands and seals, and cause the same to be filed at the Great Seal
Patent Office within six calendar months next or immediately after the date
of the reciting Letters Patent.
NOW KNOW YE, that we, the said Charles Hancock and Stephen William
Silver, do hereby declare the nature of our said Invention, and in what
manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement (that is to say):-
:-
This Invention has for its object the production of certain compounds
which will be free from some of the peculiarities of caoutchouc and other
substances employed for insulating and protecting telegraphic conductors, and
for other purposes; caoutchouc is considered a better material for electric
insulation than any other substance at present used for that purpose,
but from its tough and very elastic properties it cannot of itself be rendered

page_text: so uniformly plastic as to pass through the dies ordinarily used for covering
telegraphic wires or conductors. In order to obviate this peculiarity of
caoutchouc we propose to combine caoutchouc with a milk or gum the pro-
duce of a tree called sapota mulieri or bullet tree, which is found in British
Guiana and elsewhere, and to which the term ballata has been occasionally
applied. This milk or gum possesses similar insulating properties to caoutchouc,
we combine caoutchouc and ballata by mastication, rolling, or solution accord-
ing to one of the several processes well known among india-rubber and gutta
percha manufacturers. By one or other of these processes the caoutchouc
and ballata are thoroughly mixed, when they form one homogeneous.com-
pound of great flexibility, strength, and toughness, which is a non-absorbent
of water and a non-conductor of electricity, and which when warmed can be
easily used for covering telegraphic conductors by passing it through dies,
and which may be vulcanized to any required degree of hardness.
The following compound is suitable for a soft vulcanized substance.
Two pounds of india-rubber, one pound of ballata, and nine ounces of
sulphur; these materials being combined, are exposed for about two hours to
a temperature of 285° F., but the time may vary from two to six hours, the
temperature from 260° F. to 280° F., as is well understood by persons con-
versant with vulcanization.
$
The following compound is suitable for a hard vulcanized substance :-Two
pounds of india-rubber, one pound of ballata, and one and a quarter pound of
sulphur. These materials being combined are subjected for five hours to a
temperature of 280° F., but the time may vary from four to eight hours, and
the temperature from 260° F. to 300° F.
The following compounds are suitable for substances not to be vulcanized.
No. 1. Three pounds of ballata, three pounds of caoutchouc, two pounds of
vulcanized caoutchouc pulverized or ground to powder.
No. 2. Two pounds of ballata, six pounds of caoutchouc, two pounds of
colcotha.
No. 3. Three pounds of ballata, and one of caoutchouc.
No. 4. Three pounds of ballata, one pound of shellac, paraffine, or rosin,
pitch, tar, marine glue, gum copal, gum mastic, or other gum insoluble in
water.
No. 5. India-rubber, gutta percha, and ballata in equal proportions.
No. 6. Gutta percha and ballata.
The foregoing materials are combined by rolling, mastication, or solution.
The compounds before mentioned can, when in a plastic state, be moulded
into various articles as may be required; for which purpose we prefer to

page_text: employ metal moulds. The substance called ballata when treated by mastica-
tion or solution, or its compounds, may be applied upon cloth and other fabrics
either by rolling or spreading, as is well understood in applying caoutchouc.
The ballata and its compounds may be made into hose, tubing, and driving
bands by rolling the compounds into suitable thicknesses, or by cementing
strips of cloth or leather together with the ballata and its compounds, or we
roll or make the ballata and its compounds into sheets, strips, and belts or bands
suitable for driving machinery and for other purposes. We combine sulphur
with ballata and caoutchouc, and then subject them to heat so as to form an
elastic or hard substance similar to horn in the way ordinarily used for
obtaining the same results with caoutchouc and sulphur; or we vulcanize the
ballata or its compounds by the cold or chloride of sulphur process which is
well understood by caoutchouc manufacturers.
For the insulation of electric conductors we wind round, coat, or cover the
conducting wires with strips of india-rubber in one or more layers, and then
consolidate the several laps by subjecting them to the action of steam or heated
'vapour, we afterwards apply a second coating of india-rubber and ballata, or
'ballata alone, 'or its compounds in a plastic state, and thus make the joints
and seams of the strips of india-rubber more secure. In some cases we first
insulate the wire with the several plastic compounds, or some of them herein-
before set forth through dies, and afterwards lap or wind, or otherwise apply
tapes and fillets of caoutchouc upon such plastic compounds.
Having now described the nature of our said Invention, and in what manner
'the same is to be performed, we hereby declare that we claim as the Invention
intended to be secured by the said Letters Patent, the several compounds and
substances 'above set forth for electric insulation and other purposes.
In witness whereof, we, the said Charles Hancock and Stephen William
Silver, have hereunto set our hands and seals, the Eleventh
day of June, in the year of our Lord One thousand eight hundred
and sixty-three.
:
CHARLES HANCOCK, (L.S.)
(L.S.)
S. Wч. SILVER.