IMPROVE- MENTS IN RE-WORKING COMPOUNDS OF INDIA-RUBBER AND SULPHUR,. AND IN.' INSULATING TELEGRAPHIC WIRES OR CONDUCTORS
Year: 1860

page_text: PROVISIONAL SPECIFICATION left by William Hooper at the Office of
the Commissioners of Patents,, with his Petition, on the 6th January
1860.
I, WILLIAM HOOPER, of Miteham, in the County of Surrey, India-rubber
Manufacturer, do hereby declare the nature of the Invention for "IMPROVE-
MENTS IN RE-WORKING COMPOUNDS OF INDIA-RUBBER AND SULPHUR,. AND IN.'
INSULATING TELEGRAPHIC WIRES OR CONDUCTORS," to be as follows:-
This Invention has for its object improvements in re-working compounds of
india-rubber and sulphur, and in insulating telegraphic wires or conductors.
In re-working compounds of india-rubber and sulphur, I reduce the same to a
pulp by grinding them with naptha or solvent, and I add to this mixture raw
india-rubber and sulphur: In this state the mixture is moulded, or otherwise.
brought to the form desired, and is afterwards exposed to heat to cure it, as is
ordinarily practised in curing compounds of india-rubber and sulphur. When
copper wires or conductors are coated with compounds of india-rubber and
sulphur, the sulphur is found to eat injuriously into the substance of the copper
wire;
to avoid this I coat the wire with a layer of copper or other metal before
applying the compound containing sulphur. In applying the covering of
copper or other metal to the copper wire, I carefully avoid soldering or uniting
the two metals by fusion, or otherwise'; and I am aware that copper wire
tinned has before been coated with compounds of india-rubber and sulphur,
and has then been submitted to heat; to vulcanize or harden the coating; · but

page_text: this I find does not produce the desired effect, in consequence of the union
between the two metals. In coating copper wire with copper or other metal
for the purpose of my Invention, I in some cases draw a tube on the wire, or
I lap it round with thin sheet metal; and in some cases, in order to keep the
covering metal at a distance from the wire, I interpose a layer of paper or
fibre saturated with tannate of gelatine, tannin, and collodion, or tannin and
shellac combined or separate between the two. In some cases I coat
copper wire with collodion, or with one or more of the aforesaid tannates or
compounds containing tannin, and then with a compound of india-rubber and
sulphur, and subject the whole to heat to vulcanize or harden the india-rubber.
I find that this coating of collodion serves to prevent the sulphur injuring the
copper wire. I prefer also, before coating wires or conductors with india-
rubber and sulphur, and converting the same into the hard material known as
vulcanite, to coat it with natural india-rubber, and to apply the composition of
india-rubber and sulphur immediately over and in contact with it; this coating
of india-rubber I find tends to preserve the wire or conductor in the centre of
the insulating material, it becomes itself vulcanized or hardened during the
curing process. In some cases I lap cotton or fibre round the wire, then
cover it with india-rubber and sulphur, and, convert the same into vulcanized
india-rubber or vulcanite. I also, before exposing wires or conductors coated
with india-rubber and sulphur. to heat,. to convert the coating into vulcanite,
cover the same with strands of fibre or wire; this covering protects the coating.
of india-rubber and sulphur during the curing operation, and afterwards adds
strength to the coated and covered conductor, and protects it from violence.
or
"cure
Another part of this Invention has for its object improvements in the
making of joints in the coatings of electric telegraph conductors when using
india-rubber with sulphur. It is well known that surfaces of vulcanite or
vulcanized india-rubber cannot be effectually joined together by any known
cement, and although it has been proposed to: insulate wires and other forms
of metallic conductors for electric. telegraphs by the use of india-rubber and
by gutta percha, and by both those matters, and to coat the same over with
"such
sulphur compounds of india-rubber, and to "convert."
coatings, at
present no complete mode is known of producing joints between
lengths of electric telegraph conductors so. insulated and coated. Now,
according to my Invention, in order to make a joint between two lengths of a
metallic conductor which has been previously insulated and coated with
vulcanite or vulcanized india-rubber, I solder or otherwise, connect the ends of
the metal conductors, and coat the joint with india-rubber uncombined with
sulphur, to insulate the same, and this may be done by winding a narrow fillet

page_text: spirally around the wire, or otherwise; then around this I apply a quantity of
a suitable sulphur compound of india-rubber, and over this I put a sheet of
vulcanized india-rubber, so that the same overlaps the ends of the vulcanized
or vulcanite coatings of the other parts of the metallic conductor, the
unconverted sulphur compound of india-rubber coming between all parts of
the vulcanite or vulcanized india-rubber where a cementing or combining of
the surfaces is desired. These parts are to be well bound together or clamped,
so as to hold them in close contact in all parts during the time that the joint
is being subjected to the requisite heat for converting the sulphur compound
of india-rubber which has been introduced between the lapping surfaces. In
place of interposing a composition of india-rubber and sulphur between the
native india-rubber and the vulcanized india-rubber, the two latter are
placed directly in contact with each other, the surfaces which come in contact
being coated with naptha or solvent, or with a solution of iudia-rubber, sulphur
being by preference mixed with the solvent or solution.