IMPROVEMENTS IN THE TREATMENT OF INDIA-RUBBER AND OTHER MATERIALS 80 AS TO RENDER THEM SUITABLE FOR INSULATING TELEGRAPH WIRES, AND IN THE METHOD OF APPLYING SUCH INSULATING MATERIALS; AND ALSO FOR RENDERING INDIA-RUBBER SO TREATED SUITABLE FOR RE-MANUFACTURE.
Year: 1871

page_text: ETTERS PATENT to Thomas Thomas Peter Bruce Warren, of Tam-
worth House, Mitcham, in the County of Surrey, Chemist and
Electrician, for the Invention of "IMPROVEMENTS IN THE TREATMENT
OF INDIA-RUBBER AND OTHER MATERIALS 80 AS TO RENDER THEM SUITABLE
FOR INSULATING TELEGRAPH WIRES, AND IN THE METHOD OF APPLYING SUCH
INSULATING MATERIALS; AND ALSO FOR RENDERING INDIA-RUBBER SO TREATED
SUITABLE FOR RE-MANUFACTURE.
"
Sealed the 25th August 1871, and dated the 28th February 1871.
PROVISIONAL SPECIFICATION left by the said Thomas Thomas Peter
Bruce Warren at the Office of the Commissioners of Patents, with
his Petition, on the 28th February 1871.
I, THOMAS THOMAS PETER Bruce Warren, of Tamworth House,
Mitcham, in the County of Surrey, Chemist and Electrician, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE
TREATMENT OF INDIA-RUBBER AND OTHER MATERIALS, SO AS TO RENDER THEM
A

page_text: SUITABLE FOR INSULATING TELEGRAPH WIRES, AND IN THE METHOD OF APPLYING
BUCH INSULATING MATERIALS, AND ALSO FOR RENDERING INDIA-RUBBER SO TREATED
SUITABLE FOR RE-MANUFACTURE," to be as follows:-
The first part of my improvements has for its object the means of
obtaining the electrical advantages of india-rubber, so as to ensure its
durability without vulcanizing or the aid of sulphur in any form, and
further enables me to dispense with the introduction of india-rubber
solvents, which operate so deleteriously unless submitted to the
vulcanizing process.
My improvements further enable me to apply over a thinly insulated 1
wire a cheap protective material, which is in itself an insulator and
exerts no injurious effect upon india-rubber.
In carrying out these improvements I submit the india-rubber
insulated wires or telegraph cores previously consolidated, as herein-
after described, to the netion of iodine, bromine, or chlorine dissolved
in such menstrua which can neither dissolve india-rubber nor exert any
action upon it, or by burying insulated wires in French chalk with which
iodine or bromine has been previously triturated. The solvents which
I prefer arc water, alcohol, wood naptha, or mixture of alcohol and
water, to which iodine or bromide of potassium may be added so as to
obtain a more saturated solution. In the case of chlorine, waler alone
is employed under the assistance of pressure. The strength of the
solutions must depend upon the hardness required to be given to the
india-rubber, and the depth to which the iodine, bromine, or chlorine
should extend must be regulated by the time of immersion. For giving
a great degree of hardness I prefer either immersion in bromine or
melted iodine, or passing the insulated wire through them for two or
more successive times. In cases where a gradual action is required I
prefer an aqueous solution of iodine or bromine, to which iodide or
bromide of potassium may be added according to the strength required.
The temperature of these solutions is regulated between 60 and 70
degrees Fahrenheit. The proportions which I prefer to employ are
250 grains of iodine or bromine to every gallon of water in which 1000
grains of iodide or bromide of potassium have been previously dissolved.
The usual time of immersion in the iodine solution is about 36 hours,
and with the bromide about 8 hours. The iodine solution is found to
give the most favorable results. The india-rubber may be either in
its pure state or mixed with substances other than sulphur, as French

page_text: chalk, plumbago, silica, asphalt, gum thus, or gutta percha, or other
suitable substances. The conductors, whether iron or copper, may be
coated with tin, and a mixture becoming adhesive by heat may be
applied so as to ensure the adhesion of the india-rubber to the conductor
under the process of consolidating. This mixture consists of equal
parts or thereabouts by weight of shellac and gutta percha, and 4 parts
of Canada balsam to which a small proportion of iodine may be added,
or any other suitable compound may be employed. The india-rubber
or its compounds may be applied spirally, longitudinally, or by means
of dies. The coatings when applied spirally or longitudinally are con-
solidated according to this part of my improvements by being coiled
round iron drums or cylinders, which afterwards aro heated by air,
steam, or water, applied invariably inside the cylinder, so as to keep the
insulated wires perfectly dry until consolidated, or the wire in coils may
be placed in a chamber heated by means of dry air or by the circulation
of steam or water in pipes.
I
By these methods I am able to keep the insulated wires perfectly
under control during the heating, and can inspect the operation during
its progress.
Each coating, when more than one is required, may when consolidated
be submitted to the action of the solution of iodine preferably in alcohol.
Before applying a second or subsequent coating a layer of the shellac
and gutta percha compound previously described may be applied.
When india-rubber or its compounds are applied by means of dies,
unless another coating is required, I pass the same through a solution of
bromine or iodine, so as to prevent the adhesion of the coils to one
another.
When india-rubber or its compounds are applied longitudinally it may
be preferable to bind the same with cotton tape or other suitable
material, or to pass the same through a die or between heated rollers so
as to ensure the adhesion of the edges.
For making joints in these insulated wires in accordance with my
improvements, the ends of the conductor being united the insulator is
tapered down and the surface pared off for a few inches on either side.
The insulator is afterwards applied longitudinally or spirally, and when
completed is tightly bound with tape extending a few inches beyond the
ends of the joint. Heat is gradually applied to 240 degrees or 280
degrees Fahrenheit so as to solidify the whole. When cooled the tape
A 2

page_text: covering is removed, and the joint dipped in melted iodine, or bromine
may be painted over it and such parts as have been subjected to the
heat.
In insulating telegraph wires according to my improvements I may
combine two or more of these operations.
Insulator joints may also be made in these wires by vulcanizing, as
is well known to telegraph core manufacturers.
5
In remanufacturing india-rubber according to my improvements
which has been treated with iodine or bromine I submit the same to a
dry air heat of 280 degrees Fahrenheit for 4 or 6 hours, so as to expel 1
the iodine or bromine, and afterwards mix the same with a fresh
quantity of india-rubber, which is thus rendered suitable for any of the
ordinary india-rubber manufactures.
According to another part of my improvements I am able to obtain
from certain vegetable oils by means of sulphur a substance which no 1
longer possesses a greasy or oily character, and is adapted for giving
greater thickness of bulk to insulated wires, and which may be used as
a substitute for hemp on telegraph cores. The oils are previously
purified by boiling and straining, and when at their boiling points are
saturated with sulphur. The excess of sulphur which falls to the 2
bottom of the vessel is removed through a pipe fitted into the bottom.
The temperature is then allowed to riso gradually until the chemical
action takes place, which results in the production of a spongy clastic
substanco.
The oils which I prefer to employ are linseed oil, nut oil, poppy seed a
oil, or mixtures of two or more of them. The proportions of sulphur
which I find are required for recently drawn samples are for linseed oil,
about one-fourth its weight of sulphur; for nut oil, about one-half its
weight of sulphur; and for poppy seed oil, about its own weight of
sulphur. The proportions however will vary with the age and condition
of the oils.
When two or more of these oils are mixed together the quantity of
sulphur required to be added will be in the above proportion for the
weights separately of each oil so mixed.
The product resulting from the action of sulphur on oils has been
long known to chemists, and can be obtained from oils containing olcic

page_text: cid, such as linseed oil, poppy seed oil, rape seed oil, or nut oil. In
pplying this substance to telegraph cores it is mixed with one or more
of the following materials:-French chalk, silica, carbonate of lime or
naguesia, plumbago, bitumen, asphalt, pitch, and the mineral hydro-
arbons, colophane, gum thus, shellac, or Canada balsam, metallic
tearates, or other salts obtained by the action of fatty acids on basic
ubstances, as is well-known to chemists.
The following proportions I find to answer very well :—
Linseed oil product
Nut oil product
-
Poppy seed oil product
Asphalt, bitumen, or pitch
Gum thus
Shellac
Colophane
3 pounds.
->
2 pounds.
4 pounds.
2 pounds.
1 pound.
Carbonate magnesia or carbonate of
lime or plumbago
Stearate of lead or other substances
having chemically a similar con-
stitution as common soap
.French chalk or silica
2 pounds.
2 pounds and a half.
1 pound.
-
1 pound and a half.
2 pounds.
The hardness of the compound may be increased by a further addition
of asphalt or by reducing the quantity of stearate of lead or omitting it
altogether.
The addition of Canada balsam will produce a much softer compound
paraffin, ozokerite, or similar mineral hydrocarbons will give a more
easily fusible product.
The whole or part of the shellac may be replaced by adding about
double its weight of colophane.
When it is required to add very large quantities of pitch the proportion
of "gum thus" must be increased with or without the addition of one
or more of the mineral hydrocarbons.
The carbonate of lime, magnesia, and plumbago are omitted when
it is desired to increase the insulating property of the compound, and
in which case I prefer using stearate of lead instead of substances o
similar character.

page_text: The French chalk, silica, or plumbago, either separately or together,
are intended to be mixed with the oils after saturating the same with
sulphur. The other matters are incorporated by grinding or masticating
in the manner well-known to manufacturers.
The compound or compounds thus obtained are intended to be applied
by means of dies or grooved rollers alternating or otherwise with a
coating of the shellac and gutta percha compound.
The core thus covered is afterwards lapped round with canvas or
any textilo or fibrous material may be laid on, as is well known to
manufacturers of telegraph cores and cables.
Before applying this compound the core may be previously tested
electrically in water, as is well known, in which case the surface of the
core should be well dried before putting it on, and may be coated with
the mixture of shellac and gutta percha previously described.
By this part of my improvements I am able by increasing the diameter
of an insulated wire to enhance its mechanical value in reducing the
chance of accident during mauufacture into cables.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Thomas Peter Bruce Warren in the Great
Seal Patent Office on the 28th August 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
THOMAS PETER BRUCE WARREN, of Tamworth House, in the County
of Surrey, Chemist and Electrician, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-eighth day of February, in the
year of our Lord One thousand eight hundred and seventy-one, in the
thirty-fourth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Thomas Thomas Peter Bruce
Warren, Her special licence that I, the said Thomas Thomas Peter
Bruce Warren, my executors, administrators, and assigns, or such others ;
as I, the said Thomas Thomas Peter Bruce Warren, my executors, ad-
ministrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein

page_text: 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 "IMPROVEMENTS IN THE TREAT-
MENT OF INDIA-RUBBER AND OTHER MATERIALS, SO AS TO RENDER THEM SUITABLE
FOR INSULATING TELEGRAPH WIRES, AND IN THE METHOD OF APPLYING SUCH
INSULATING MATERIALS, AND ALSO FOR RENDERING INDIA-RUBBER SO TREATED
SUITABLE FOR RE-MANUFACTURE," upon the condition (amongst others) that
I, the said Thomas Thomas Peter Bruce Warren, my exccutors or
administrators, by an instrument in writing under my, or their, or one
of their hands and scals, 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 Thomas Thomas Peter Bruce
Warren, do hereby declare the nature of the said Invention, and in
what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement thereof, that is to
say:
The first part of my improvements has for its object the means of
obtaining the electrical advantages of india-rubber, so as to insure its
durability without vulcanizing, or the aid of sulphur in any form, and
further enables me to dispense with the introduction of india-rubber
solvents, which operate so deleteriously unless submitted to the vulca-
nizing process.
My improvements further enable me to apply over a thinly insulated
wire, a cheap protective material, which is in itself an insulator, and
cxcrts no injurious effects upon india-rubber.
It is well known that india-rubber as applied for the purpose of
insulating requires to be submitted to a temperature sufficiently high
to consolidate it, or to reduce it to the condition of a perfect and
homogeneous covering, and it is further well known that the act of
consolidating induces a decomposing action on the india-rubber, which
is characterized by its becoming soft and sticky on exposure to the air
for a short time.
It is also well known that the only method which heretofore has
been found successful in arresting this tendency to decay is vulcanization

page_text: which is effected either by mixing sulphur with india-rubber, and
submitting the same to high temperatures, or by heating india-rubber
at high temperatures under another coating of india-rubber containing
sulphur.
I would here remark that I am aware that Letters Patent, dated 1846,
No. 11,147, have been granted to Mr. Alexander Parkes, for acting upon
india-rubber with iodine, bromine, and chlorine, in the state of vapors,
with the addition of vapors of india-rubber solvents, and for suspending
articles of india-rubber in the same solvents, in which chloride of sulphur
and other "changing" agents have been dissolved.
In carrying out my improvements in treating india-rubber, so as to
render the same suitable for insulating telegraph wires, I submit the
india-rubber insulated wires or telegraph cores, previously consolidated
as herein-after described to the action of iodine, bromine or chlorine,
dissolved in such menstrua as can neither dissolve india-rubber nor excrt
any action upon it, or by burying insulated wires in French chalk with
which iodine or bromine has been previously triturated.
In the application of this part of my Invention, I first triturato
the iodine or bromine with about an equal weight of French chalk, so
as to disseminate or divide them thoroughly, and I afterwards mix in the
remaining portion of the French chalk in divided quantities until
the proper strength or state of dilution has been obtained. I find when
applying either iodine or bromine in this way that about one ounce
(avoirdupois) of iodine or bromine to about twenty pounds of French
chalk forms a very good proportion, but more or less French chalk
may be employed according to the effect which it is desired to produco
upon the india-rubber.
The solvents which I prefer to employ are water, alcohol, wood
naptha, or mixtures of alcohol and water, to which iodide or bromide
of potassium may be added so as to obtain a more saturated solution.
In the case of chlorine water alone is employed under the assistance of
pressure. By the term of alcohol I can "spirit of wine," which may
be methylated or otherwise.
When operating with chlorine a salt or substance capable of giving
off chlorine gas, when suspended or dissolved in water, may be used, and
for such purpose I find that the chlorinated alkalies or alkaline carths,
which are known as disinfectants, may be conveniently employed; I
prefer however to generate the chlorine gas in a separate vessel, and

page_text: to pass the same into a suitable receiver containing water, and in which
he coils are placed, and I allow the chlorine to be generated so as to
keep the water saturated until the india-rubber shall havo been
sufficiently acted on.
The pressure under which the chlorine is applied will vary with the
temperature, but I find that at the temperature of 60° Fahrenheit a
inch
pressure of about five or ten pounds per square may be employed.
When the chlorine is generated by any of the ordinary methods, it is
desirable to pass the gas through water so as to free it as much as
possible from acid or other matters contained in the generator before
passing it into the receiver, as is well understood by chemists, since the
addition of large quantities of hydrochloric or sulphuric acid to the chlorine
solution injuriously affects or hardens the surface of the india-rubber.
The strength of the solutions must depend upon the hardness required
to be given to the india-rubber, and the depth to which the iodine,
bromine, or chlorine should extend must be regulated by the time of
immersion, as will be readily ascertained by experiment.
The strength of the chlorine solution is controlled by adjusting the
pressure under which it is allowed to act as before specified.
For giving a great degree of hardness I prefer either immersion in
bromine or melted iodine, or passing the insulated wire through them
for two or more successive times.
When employing bromine or iodine in this way it is desirable after
placing it in a suitable and enclosed vessel or trough, to cover it with
water so as to prevent the noxious effect of their vapours upon the
operator.
I find when it is desired to give to the india-rubber insulating covering
this increased hardness that the action either of the bromine or iodine
should extend only to the external surface or coating of the insulated
wire, and in order more effectually to ensure this I employ a coating
which will arrest or impede their action. For this object a layer or
coating of india-rubber compounded with French chalk or similar
substances forms a mechanical barrier to their ingress to the inner layers
of india-rubber.
In cases where a gradual action is required I prefer an aqueous
solution of iodine or bromine, to which iodide or bromide of potassium
uay be added according to the strength required. The temperature of

page_text: these solutions is regulated between 60° Fahrenheit and 70° Fahrenheit.
The proportions which I prefer to employ are 250 grains of iodine or
bromine to every gallon of water, in which 1,000 grains of iodide
or bromide of potassium have been previously dissolved. The usual time
of immersion in the iodine solution is about 36 hours, and with the
bromine about 8 hours. The iodine solution is found to give the most
favourable results.
When replenishing these solutions it will be necessary to add the
solution of iodide or bromide of potassium formed by dissolving 1,000
grains of either salt in one gallon of water, and taking care that after 1
the solution is thoroughly saturated with iodine or bromine a large
excess remaius at the bottom of the solution so as to maintain the whole
in a perfectly saturated state and of uniform strength.
The india-rubber treated in accordance with this part of my Invention
may be either in its pure state or mixed with substances other than 1
sulphur, as French chalk, plumbago, silica, asphalte, gum thus, gulta
percha, or other suitable substances.
When india-rubber is compounded with any of these substances I
find that the addition of a small quantity either of iodine or bromine to
such compound may be made before applying the same to the wire, in 2
which case they should be previously divided or reduced with French
chalk in the manner proviously directed.
I find that when india-rubber is compounded with asphalt or other
bituminous matters the action of the iodine, bromine, or chlorine must
be modified either by reducing the time of immersion or using their 2
solutions of about one-half the strength.
The conductors, whether iron or copper, may be coated with tin, and
a mixture or compound becoming adhesive by licat may be applied so
as to ensure the adhesion of the india-rubber to the conductor under
the process of consolidating. This mixture or compound consists of 30
equal parts or thereabouts by weight of shellac and gutta percha and
4 parts of Canada balsain, to which a small proportion of iodine may be
added, or any other suitable compound may be employed, such, for
instance, as a compound of shellac and india-rubber.
It is well known that india-rubber when in contact with certain 35
metals, and more especially copper wire, becomes soft and oozes out in

page_text: a semifluid state; I find that by the addition of a small proportion of
iodine to the mixture or compound applied over the conductor, as above
stated, I am able to prevent this change in the india-rubber by acting
during the heating or consolidating process on the surface of the india-
rubber contiguous to the conductor.
The india-rubber or its compounds may be applied spirally, longi-
tudinally, or by means of dies. The coatings when applied spirally
or longitudinally are consolidated according to this part of my im-
provements by being coiled round iron drums or cylinders, which
afterwards are heated by air, steam, or water, applied invariably insido
the cylinder so as to keep the insulated wires perfectly dry until con-
solidated, or the wire in coils may be placed in a chamber heated by
means of dry air or by the circulation of steam or water in pipes. By
these methods I am able to keep the insulated wires perfectly under
control during the heating process, and can inspect the operation during
its progress.
I would here remark that the india-rubber coatings when consolidated
by any of the well-known methods of heating may be submitted accord-
ing to the first part of my improvements to the action of iodine, bromine,
or chlorine, as herein specified.
I find that in order to ensure the gradual heating of the coils the
droms or cylinders should be covered with a substance having a low
conducting power for heat, such as felt or other suitable material, or
the temperature of the steam or water in the cylinder should be
gradually raised, as is well known.
Each coating, when more than one is required, may when consolidated
be submitted to the action of the solution of iodine, preferably in alcohol,
as previously described.
Before appying a second or subsequent coating a layer of the shellac
O and gutta percha mixture or compound may be applied, or any other
suitable compound, as previously described.
I find that the addition of iodine to this mixture or compound, or to
similar compounds when employed between the coatings affects the
india-rubber during the consolidating process, but not in any way
5 prejudicially.

page_text: When india-rubber or its compounds are applied by means of dies
unless another coating is required I pass the same through a solution
of bromine or iodine so as to prevent the adhesion of the coils to one
another.
When india-rubber or its compounds are applied longitudinally it
may be preferable to bind the same with cotton tape or other suitable
material, or to pass the same through a die or between heated rollers,
so as to ensure the adhesion of the edges.
For making joints in insulated wires treated in accordance with my
improvements (the ends of the conductor being united) the insulator is
tapered down, and the surface pared off for a few inches on each side.
The insulator is afterwards applied longitudinally or spirally, and when
completed is tightly bound with tape, extending a few inches beyond
the ends of the joint. Heat is gradually applied to 2:10° to 280 degrees
Fahrenheit so as to solidify the whole. When cooled the tape covering 1
is removed, and the joint dipped into melted iodine, or bromine may
be painted over it and the parts which have been subjected to the
heat.
In insulating telegraph wires according to my improvements two
or more of the operations previously described may be employed in
combination.
Insulator joints may also be made in these wires by vulcanizing, as
is well known to telegraph core manufacturers.
In manufacturing india-rubber according to my improvements which
has been treated with iodine or bromine, I submit the same to a 2
dry air heat of 280° Fahrenheit for 4 or 6 hours so as to expel the greater
portion, or as much as may be desired of the iodine or bromine.
and afterwards mix the same with a fresh quantity of india-rubber,
which is thus rendered suitable for any of the ordinary india-rubber
manufactures.
3
I find that by varying the time to which the india-rubber is submitted
to this process more or less of the effect produced on the india-rubber
or iodine or bromine may be removed, so that by increasing the time the
india-rubber will become almost entirely soluble in its ordinary solvents,
whilst a shorter time will soften it and render it fit for regrinding or 3
masticating.

page_text: I would here remark that when chlorine has been employed in the
treatment of the india-rubber both the temperature and time of heating
may be reduced so as to render it suitable for reworking.
I find that india-rubber which has been acted upon by iodine, bromine,
or chlorine is more easily affected by sulphur during the vulcanizing
process than in its raw or ordinary-states.
According to another part of my improvements I am able to obtain
from certain vegetable oils by means of sulphur a substance which no
longer possesses a greasy or oily character, and is adapted for giving
y be used as
greater thickness or bult to insulated wires, and which may l
a substitute for hemp on telegraph cores.
It is well-known that india-rubber in its ordinary state is liable to
soften and become sticky when placed in contact with greasy or oily
substances, and more especially when heated. I find that these com-
pounds exert a preservative action on india-rubber in its ordinary state
when mixed with it or even when submitted to high temperatures. It
also enables gutta percha cores to resist the softening effect of moderately
high temperatures. The oils are previously purified by boiling and
straining, and when at their boiling points are saturated with sulphur.
The excess of sulphur which falls to the bottom of the vessel is removed
through a pipe fitted into the bottom. I would remark that, having
ascertained by experiment in this way the quantity of sulphur required
I use the same quantity for the same oil in bulk. The temperature is
then allowed to rise gradually until the chemical action takes place,
5 which results in the production of a spongy clastic substance. By con-
tinuing the heating the product becomes more solid and coherent, and
loses a great deal of its elasticity. This is more markedly the case
with linseed oil, which admits of being considerably modified by the
addition of the other oils herein named.
0
The oils which I prefer to employ are linseed oil, nut oil, poppy seed
oil, or mixtures of two or more of them. The proportions of sulphur
which I find are required for recently drawn samples are, for linseed oil,
about one-fourth its weight of sulphur; for nut oil, about one-half its
weight of sulphur; and for poppy seed oil, about its own weight of
5 sulphur. These proportions however will vary with the age and con-
dition of the oils, which quantity should be ascertained by experiment,
as previously described.

page_text: herein-before described, substantially in the manner and for the purposes
herein-before fully described.
In witness whereof, I, the said Thomas Thomas Peter Bruce
Warren, have hereunto set my hand and seal, this Twenty-
fourth day of August, in the year of our Lord One thousand
eight hundred and seventy-one.
THOMAS T. P. BRUCE WARREN. (L.S.)
Witness,
J. G. TONGUE,
Patent Agent,
34, Southampton Buildings,
Chancery Lane,
W.C.