IMPROVEMENTS IN ELECTRIC TELEGRAPH CONDUCTORS
Year: 1865

page_text: LETTERS PATENT to Alexander Parkes, of Birmingham, in the County
of Warwick, for the Invention of "IMPROVEMENTS IN ELECTRIC TELEGRAPH
CONDUCTORS,"
Sealed the 23rd March 1866, and dated the 21st October 1865.
PROVISIONAL SPECIFICATION left by the said Alexander Parkes, at
the Office of the Commissioners of Patents, with his Petition, on the
21st October 1865.
I, ALEXANDER PARKES, of Birmingham, in the County of Warwick, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
ELECTRIC TELEGRAPH CONDUCTORS," to be as follows:-
This Invention has for its object improvements in electric telegraph
conductors. For these purposes tubular or hollow conductors of copper
of a cylindrical or flat or other suitab e section are used, which, however,
are not new; but according to my Invention I strengthen these tubular or
hollow conductors by internal cores of steel or iron or aluminium bronze,
such interior strengthening cores being drawn or extended with the copper
conductor. In order to connect the ends of the cores and to continue the
copper conductor over such connections, I employ the process of welding
the ends when the strengthening cores are of steel or iron, and hard solder
(either brass or silver) in connecting the ends where the strengthening
cores are of aluminium bronze; then over each joint I employ a split tube
of copper or a flat tape of copper, and fasten the same by soldering.
Ip...

page_text: "
connecting ordinary copper conductors I employ silver solder, in order that
the joints may be stronger than heretofore when using soft solder, and by
using silver solder the joints are also rendered of equal conductive power
with the copper. These conductors are then coated with any of the
ordinary insulating substances, but the compound called "parkesine
preferred, and when using this description of compound it is found that
the proportions should consist of about 100, parts by weight of dissolved
cotton, 100 to 150 parts- of oil (preferring. castor oil) and 50. parts of
camphor.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Parkes in the Great Seal Patent Office on
the 21st April 1866:
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
PARKES, of Birmingham, in the County of Warwick, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of October, in the year of our
Lord One thousand eight. hundred and sixty-five, in the twenty-ninth year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Alexander Parkes, Her special licence that I, the said Alexander
Parkes, my executors; administrators, and assigns; or such others as I, the
said Alexander Parkes, my 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 therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdomof Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN ELECTRIC TELEGRAPH CONDUCTORS," upon the condition
(amongst others) that I, the said Alexander Parkes, my executors or
administrators, by an instrument in writing under my, 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 Alexander Parkes, do hereby declare
the nature of my.said Invention, and in what manner the same is to he
performed, to be particularly described and ascertained in and by the
following statement thereof. that is to say:-

page_text: This Invention has for its object improvements in electric telegraph con-
ductors. For these purposes tubular or hollow conductors of copper of a
cylindrical or flat or other suitable section are used, which, however, are not
new; but according to my Invention I' strengthen these tubular or hollow con-
ductors by internal cores of steel or iron or aluminium bronze, such interior
strengthening cores being drawn or extended with the copper conductor.
I prefer to proceed as follows:-I make a seamless tube of copper, by
preference of cylindrical form, by casting a hollow ingot and forging, rolling,
or drawing it to the required size, as is well understood in making seam-
less copper tubes. I then introduce into this tube a rod of steel or iron
of, say, about a quarter of an inch in diameter, the bore of the tube being
such as just to receive freely the steel or iron rod, which should be annealed.
and free from scale: then roll the copper tube with the rod within it,
so as to reduce the diameter to, say, one quarter of an inch,
the process
being conducted in the usual manner, and as if a solid rod of copper were
being worked. After the rolling, a wire of the desired section is made
from the rod by means of the ordinary operations of wire drawing. The
material should be carefully annealed after each passage through the rolls
and after eacli wire drawing operation. Although, as above stated,.I. prefer
to employ both the rolling and the drawing processes in reducing the
conductor to the required section, this is by no means essential, as the
compound conductor may be brought to the required section either by
rolling without drawing or by drawing without rolling. I prefer usually to
make the copper tube of such a section that there may be in the conductor
about equal weights of copper and steel or iron, but greater strength may
when necessary, be obtained by increasing the weight of steel or iron until
the proportion is, say, one of copper to two of steel or iron; other propor-
tions may, however, be employed, but I believe the most useful results to
be obtained when the proportions are as above stated. In place of an
inner rod of steel or iron, one of aluminium bronze may be substituted; it is,
however, more expensive, and, as far as I am aware, is not in other respects
superior to steel or iron. In order to connect the ends of the cores and
to continue the copper conductor over such connections, I employ the
process of welding the ends when the strengthening cores are of steel or
iron, and hard solder (either brass or silver) in connecting the ends where
the strengthening cores are of aluminium bronze; then over each joint I
apply a split tube of copper or a flat tape of copper, and fasten the same
by soldering, using, by preference, ordinary fine silver solder for the
purpose. I prefer, as far as possible, to make these joints before the

page_text: conductor has been reduced to a small diameter, and as soon as the copper
tube has thoroughly closed on the inner rod, and after making the joints
I continue the drawing down operations. When made in this manner the
joints are hardly visible in the finished conductor. Joints which are
necessarily made after the drawing down operations are complete are pro-
duced in a similar manner. These conductors may be insulated with any
of the insulating materials usually employed, such as gutta percha or india-
rubber; I prefer, however, to use the compound known as parkesine, the
methods of preparation and use of parkesine are now well understood.
For this use the ingredients of the parkesine may be mixed in the
proportion of 100 parts by weight of cotton dissolved in a suitable solvent,
100 to 150 parts of oil (preferring castor oil), and 50 parts of camphor.
In connecting ordinary copper conductors I employ silver solder, in order
that the joints may be stronger than heretofore when using soft solder, and
that the joints may be rendered equal in conductive power with the copper;
I prefer to use for this purpose ordinary fine silver solder and to apply it
by means of a blow pipe. I employ the ordinary borax flux. The con-
ductors are afterwards covered with insulating material, gutta percha or
india-rubber may be employed; I, however, prefer to use parkesine.
In witness whereof, I, the said Alexander Parkes, have hereunto set
my hand and seal, this Twentieth day of April, in the year of our
Lord One thousand eight hundred and sixty-six.
ALEXANDER PARKES. (L.S.)