IMPROVEMENTS IN ELECTRIC CONDUCTORS AND IN THE MEANS OF
Year: 1853

page_text: LETTERS PATENT to Thomas Allan, of Adelphi Terrace, in the
City of Westminster, Civil Engineer, for the Invention of
"IMPROVEMENTS IN ELECTRIC CONDUCTORS AND IN THE MEANS OF
"
Sealed the 10th February 1854, and dated the 12th August 1853.
PROVISIONAL SPECIFICATION left by the said Thomas 'Allan
at the Office of the Commissioners of "Patents, with his
Petition, on the 12th August 1853:
I, THOMAS ALLAN, of Adelphi Terrace, in the City of West-
minster, Civil Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN ELECTRIC CONDUCTORS AND IN THE
MEANS OF INSULATING ELECTRIC CONDUCTORS" to be as follows:-
The engineering as well as electrical difficulties.to the working
submarine telegraphs of any length extending beyond what has
already been done upon the plans at present in use have led to the
belief that other means were required, and that a different mode
of applying known principles and materials would be requisite to
S

page_text: obtain not only the greatest length of rope at the smallest amount
of weight, but also the fullest amount of electrical conduction. For
this purpose I propose to do away with the usual mode of an insula-
ted copper wire protected with iron, but to use and substitute as the
conductor a stout iron wire or rod, not galvanized, and therefore
maintaining the full strength of the iron, or, what is preferable, a
rope made of several iron wires together, and this then insulated.
The insulation would require to be of a material differing from the
ordinary kinds used for the insulation of copper wires; and what
I propose for the purpose is, a compound of caoutchouc, sulphur,
and coal tar, or other mixture, baked hard, and resembling in
appearance the material manufactured according to the Invention
patented by Mr. Goodyear, which itself might do with certain
modifications. By these means a submarine rope will be obtained
of less than a ton to the mile, with the greatest amount of strength
that can be acquired by iron of the best quality, whilst the con-
ducting medium will be considerably better and give less resistance
than the largest size of copper wire used for such purposes; besides,
many other electrical difficulties will be overcome not necessary
to enter upon here. The means I employ for applying the insu-
lating medium to telegraph wires are herein-after stated. The in-
sulating material when baked and prepared becomes so hard as
to be a sufficient protection against any disturbing causes that
are likely to occur, excepting within tideways and currents near
land, where the insulation can be further protected from the effects
of friction and be otherwise strengthened by an outer coating of
iron wire. In this way electrical conductors for submarine pur-
poses of great length, say 1500 or 1800 miles, will not be imprac-
ticable in a financial, engineering, and electrical point of view.
I further propose to carry out the principle to use and substitute
insulated iron wire or small strands made of several wires together,
instead of copper, for underground electrical conducters, and this,
with an insulating material of the nature described, will effect a
great saving of cost. I also propose to use for the above purposes
strands of wire of mixed metals, that is, so many iron wires with a

page_text: central core or wire of copper. By this means an equally good,
and, according to circunstances, better conductor is obtained, with
greater strength and flexibility than by means of copper or iron
alone can be acquired.
As a cheap and efficient mode of insulating electrical conductors
of copper, iron, or other metals (for subterranean, but which may
also be used for submarine purposes), I propose to do so in the
aggregate by means of a die or dies of the form and for the
purposes as herein-after described, by means of which I save a
large amount of the insulating material, whatever that may be
composed of. The object is not merely to coat or cover the wire
with two or more coatings of any insulating substance at onc
operation, but especially to so cover 3, 5, 7, or any number of
wires all at one operation, and all conjoined in one rope. For this.
purpose I place in the dic picce two or three hollow mandrils
(according to the number of coatings), the one behind the other,
the first one at the back where the wire enters having the smallest.
aperture, the second being larger, and the last the full size to
which the wire is to be covered, there being a sufficient space
between each to allow the insulating material freely to come in
contact with the wire after each successive coating. To perform
the same operation in the aggregate (say seven wires) seven such.
series of hollow mandrils will be required, and worked in similar
manner as if they were but one; and if required to be formed into.
one rope the die will require an extra mouth piece, so that the
seven wires when twice or thrice covered get again covered and.
conjoined all into one rope, as shewu in the Drawing. If a large
number were required, and for the better coiling when made, in
lieu of making it a round rope, it might be made in the form of a
belt or flat rope, which would also have an advantage in the
laying down.

page_text: SPECIFICATION in pursuance of the conditions of the Letters.
Patent, filed by the said Thomas Allan in the Great Seal
Patent Office on the 11th February 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME,
I, THOMAS ALLAN, of Adelphi Terrace, in the City of Westminster,
Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by
Her Letters Patent, bearing date the Twelfth day of August, in
the year
of our Lord One thousand eight hundred and fifty-three,
in the seventeenth year of Her reign, did, for Herself, Her heirs'
and successors, give and grant unto me, the said Thomas Allan,
Her special licence that I, the said Thomas Allan, my executors,
administrators, and assigns, or such others as I, the said Thomas
Allan, my exccutors, 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
Kingdom of Great Britain and Ireland, the Channel Islands, and
Isle of Man, an Invention for "IMPROVEMENTS IN ELECTRIC CON-
DUCTORS AND IN THE MEANS OF INSULATING ELECTRIC CONDUCTORS,"
upon the condition (amongst others) that
Allan, by an instrument in writing under my hand and seal,"
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.
•
the said Thomas
NOW KNOW YE, that I, the said Thomas Allan, do hereby
declare the nature of my 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 thereof (that is to say):
The engineering as well as the electrical difficulties to the laying
down and working subinarine telegraphs of any great. length,
extending much beyond what has already been accomplished upon
'

page_text: the plans at present known, have led to the belief that other means s
were requisite, and that a different mode of applying known?
principles and materials would be necessary to obtain not only the
greatest length of rope at the smallest amount of weight consistent
with. sufficient strength, but also the fullest amount of electrical
conduction.
.
My Invention consists in forming the electrical conductors of
submarine and subterraneau telegraphs of iron rods, wires, or
strands of wires, insulated or otherwise, in lieu of copper as now
used.
For submarine telegraphs, I substitute for the insulated copper
wire, conductors protected with iron, a stout iron wire or rod, or,
what is preferable, a rope or strand of wires, which thus forms
not only the conducting inedium but also the rope itself. When
insulated the iron need not be galvanized, thereby maintaining the
full strength of the iron, besides effecting a great saving in cost.
The insulating medium requires to be of a material differing
from that now used for the insulation of copper wires, and what I
employ for the purpose is a compound of caoutchouc, sulphur,.and
coal tar, or other similar substance, baked hard, and resembling in:
appearance the material manufactured according to the Invention. of
Mr. Goodyear, for which Letters Patent for England were granted to
Moses Poole, the 18th September 1852, and which itself might be
employed with or without certain modifications. By these means a
submarine rope will be produced of the required weight, with the
greatest amount of strength that can be obtained from iron of the
best quality, whilst the conducting. medium will be considerably.
better, and give less resistance than the copper wire now used for
such purposes, besides which many other electrical difficulties. will
be overcome, which it is not-requisite to enter upon here.
I further adapt and substitute iron wire or strands of small
wires, "insulated or otherwise, in lieu of copper for underground
electric conductors, and this, with an insulating material of the
nature before mentioned, will effect a great saving, of cost..
i

page_text: In some cases I use for the above purposes strands of wires of
two different metals, that is, six or more iron wires with a centre
core or wire of copper or zinc; by this means, according to cir-
cumstances, a better conductor can be obtained than by the use of
iron alone, and such conductors may be used for over-ground tele-
graphs and suspended by means of posts, as well as for under-
ground and submarine telegraphs. Under certain circumstances
I should employ the before-described conductors without insula-
tion at all.
The second part of my Invention consists in a cheap and
efficient mode of insulating clectric conductors of copper, iron, or
other metals (for subterranean telegraphs, but which may also be
used for submarine purposes). I insulate the conductors in the
aggregate, that is, several at a time, by means of a dic or dies of
the form and construction herein-after described, by means of
which I save a large amount of the insulating material, whatever
that may be composed of.
The object is not merely to coat or cover the wire with two or
more coatings of any insulating substance at one operation, but
especially to cover 3, 5, or 7, or any number of wires all at onc
operation, and all conjoined in one rope. For this purpose I place
in the die piece two or three hollow mandrils (according to the
number of coatings), the one behind the other, the first one at
the back where the wire enters having the smallest aperture, the
second being larger, and the last the full size to which the wire
is to be covered, there being sufficient space between each to allow
the insulating material to come freely in contact with the wire
after cach successive coating. To perform the same operation in
the aggregate (say on seven wires) seven such series of hollow
mandrils will be required, and worked in similar manner as if they
were but one; and if required to be formed into one rope the
die will require an extra mouth piece, so that the seven wires,
when twice or thrice covered separately, may be again covered and
conjoined all into one rope.

page_text: And having now described the nature of my said Invention, and
in what manner the same is to be performed, I declare that I
claim as of my Invention,-
First, the adaptation of iron rods, wires, or strands of wires, or
of strands of wires of different metals (insulated or otherwise), for
submarine and subterrancan telegraphs, as herein-before described;
and,
Second, the mode of insulating several wires at one operation,
as herein-before described.
In witness whereof, I, the said Thomas Allan, have hereunto
set my hand and scal, this Eleventh day of February, One
thousand eight hundred and fifty-four.
THOMAS ALLAN. (S.)