AN IMPROVED METHOD OF CONSTRUCTING SUBMARINE TELEGRAPH CABLES FOR THE SUPPORT OF INSULATED CONDUCTORS FOR COMMUNICATING INTELLIGENCE BETWEEN NATIONS AND FOREIGN COUNTRIES BY ELECTRICITY
Year: 1870

page_text: PROVISIONAL SPECIFICATION left by James Story at the Office of
the Commissioners of Patents, with his Petition, on the 11th
February 1870.
I, JAMES STORY, Gentleman, of Paris, Bourbon County, State of
Kentucky, in the United States of North America, do hereby declare the
nature of the said Invention for "AN IMPROVED METHOD OF CONSTRUCTING
SUBMARINE TELEGRAPH CABLES FOR THE SUPPORT OF INSULATED CONDUCTORS FOR
COMMUNICATING INTELLIGENCE BETWEEN NATIONS AND FOREIGN COUNTRIES BY
ELECTRICITY," to be as follows:-
"
According to my Invention the central portion of the cable is a flat-
chain of any desired width or thickness, so constructed as to have on both
flat sides small teeth or short sharp points, the said chain, being covered
with a web made of the strongest hemp cord, the warp. or threads
lengthwise of the web to be about double the size of those of the filling.
This web is intended to give strength to the cable and to be held firmly
to its place by the teeth or points on the chain when properly folded
around it. The points are of such length as not to penetrate through the
web, which should be made of the heavy hemp cord. Neither the chain

page_text: which is made of the best. iron or steel nor the hemp cord web which
surrounds the chain and is secured to it will offer any resistance to the
bending of the cable; hence thero is a saving of from thirty to forty
per cent. of the strain on the cable when it is coiled up for transportation
or when a curve is made in the laying. The metal chain being in the
centre will necessarily be relieved of much of the strain of the curves of
the surface or outer portion of the cable.
The metal chain is passed through hot pine tar to receive a coating
before the hemp web is put on, which coating will aid in securing the
web to it, making it as nearly as possible a solid yet a yielding
supporting body. The hemp web is stretched longitudinally to about
one half of its breaking capacity. Over the above-named body, which.
consists of the chain, pine tar, and hemp web, is a coating of prepared
gutta percha of any desired thickness. The object of this coating is to
prevent the effect of any magnetic influence from the metal in the 1
central portion of the body of the cable upon the insulated conductors;
it also protects the chain from corrosion.
On the flat sides of this chain, as above described, are placed the
insulated conducting wires, which are slightly corrugated or bent in
short curves, a series of any desired number of them being placed side 2
by side, so that the slight-curves-or corrugations will fit into each other
as, they lie flat, the wires being all cemented together with prepared
gutta percha.
.
It is believed that on a chain of two inches in width and half an inch
in. thickness at least eight of the insulated wires may be placed and
secured on cach side, and by enlarging and strengthening both the chain
and the web another series of insulated wires may be placed over them.
There are therefore sixteen conducting wires on each side, each of the
scries of the insulated wires being encased separately in sheet gutta
percba, the first scries being firmly attached to the body of the cable by
a solution of prepared gutta percha, and the second scries attached to
the first in the same manner. By increasing the width and thickness of
the base or body of the cable any desired number of the conducting
wires may be added.
In preparing the conducting wire it is first coated with prepared gutta
percha after it is covered with a web made of silk cord or cotton, thic
cords being longitudinal with the wire, and the whole being saturated
and cemented with gutta percha, so. that cach wire will be perfectly

page_text: insulated from the others in the series, and each covering of itself
capable of sustaining a weight of at least sixty-six pounds without strain
upon the wire.
The object of corrugating the conducting wires is to allow them more
readily to accommodate themselves to the bending of the cable. The
insulated wires being secured to the body of the cable, as abovo
described, the whole is covered by another web made of hemp cord, the
same as before described, except that it is put on without being
stretched, so that it may yield sufficiently without breaking on the long
side of the curve; it is thoroughly saturated with gutta percha so as
to receive and hold a coating of sea sand, over which is spread another
coating of a preparation of pine tar and zinc paint, and another coating
of sand.
One advantage of this preparation is that it will yield without
cracking or separating, and so prevent marine animals and insects from
eating into the cable to expose the insulated wires. The zinc paint and
pine tar coating will adhere to the outside covering and make the whole
a compact body. Over the sanded coating is placed and firmly cemented
one or more thicknesses of sheets of prepared gutta percha, and the
outside or surface of the whole cable is bound around with small wiro
for the purpose of pressing the whole. compactly together, and pro-
tecting the outer surface from injury in the shipping and laying of the
cable and in the wear thereof. The whole is completed by being
varnished over with a coat of pine pitch.
Where it is desirable to use a lighter cable a plate of iron, steel,
or sheet metal may be used as a substitute for the chain in the centre,
as above described.