IMPROVEMENTS IN THE CONSTRUCTION OF THE BALANCING APPARATUS OR IMITATION Telegraph Line CONSTRUCTION OF THE BALANCING APPARATUS OR IMITATION TELEGRAPH LINE OR CABLE TO BE USED IN DUPLEX OR OTHER TELEGRAPHY, ALSO OF ELECTRIC CONDENSERS AND RESISTANCES
Year: 1875

page_text: LETTERS PATENT to Herbert Arnaud Taylor, of 7, Pope's Head Alley,
Cornhill, and Alexander Muirhead, of 159, Camden Road, in the
County of Middlesex, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF THE BALANCING APPARATUS OR IMITATION Telegraph Line
CONSTRUCTION OF THE BALANCING APPARATUS OR IMITATION TELEGRAPH LINE
OR CABLE TO BE USED IN DUPLEX OR OTHER TELEGRAPHY, ALSO OF ELECTRIC
CONDENSERS AND RESISTANCES.”
Sealed the 20th July 1875, and dated the 24th February 1875.
PROVISIONAL SPECIFICATION left by the said Herbert Arnaud Taylor
and Alexander Muirhead at the Office of the Commissioners of
Patents, with their Petition, on the 24th February 1875.
We, HERBERT ARNAUD TAYLOR, of 7, Pope's Head Alley, Cornhill,
and ALEXANDER MUIRHEAD, of 159, Camden Road, in the County
of Middlesex, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE CONSTRUCTION OF THE BALANCING APPARATUS OR IMITATION
TELEGRAPH LINE OR CABLE TO BE USED IN DUPLEX OR OTHER TELEGRAPHY, ALSO
OF ELECTRIC CONDENSERS AND RESISTANCES," to be as follows:―
With paper pulp is mixed a substance such as black lead (plumbago)

page_text: or precipitated metals, gold, silver, copper, or other good conducting
substance, by which a moderate conducting power is imparted to the
paper produced from the pulp. The paper so prepared is arranged
between alternate layers of a di-electric, which may consist of paper
treated with paraffin, wax of gutta percha, or mica. In condensers or
accumulators thus prepared the conducting paper takes the place of the
metallic sheets (tinfoil or lead) hitherto generally employed.
To form the imitation telegraph line this conducting paper, insulated
as in the condenser by sheets of a di-electric material, is so arranged by
connecting a number of the sheets, either in continued or parallel circuit,
that the electrical properties of the telegraph line or cable are imitated,
so that uniformly throughout the imitation line the (conductive)
resistance bears the same ratio to the electrostatic capacity as the
resistance (either total or per unit of length) of the telegraph line or
cable bears to its electrostatic capacity.
Paper made as described above may be used in constructing standards
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Herbert Arnaud Taylor and Alexander Muirhead
in the Great Seal Patent Office on the 24th August 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, HERBERT
ARNAUD TAYLOR, of 7, Pope's Head Alley, Cornhill, and ALEXANDER
MUIRHEAD, of 159, Camden Road, in the County of Middlesex, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fourth day of February, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc.
cessors, give and grant unto us, the said Herbert Arnaud Taylor and
Alexander Muirhead, Her special license that we, the said Herbert
Arnaud Taylor and Alexander Muirhead, our executors, administrators,
and assigns, or such others as we, the said Herbert Arnaud Taylor
and Alexander Muirhead, our executors, administrators, and assigns,

page_text: 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
5 Isle of Man, an Invention for "IMPROVEMENTS IN THE CONSTRUCTION
OF THE BALANCING APPARATUS OR IMITATION TELEGRAPH LINE OR CABLE TO BE
USED IN DUPLEX OR OTHER TELEGRAPHY, ALSO OF ELECTRIC CONDENSERS AND
RESISTANCES," upon the condition (amongst others) that we, the said
Herbert Arnaud Taylor and Alexander Muirhead, our executors or
1 administrators, by an instrument in writing under our or their hands
and seals, or under the hand and seal of one of us or them, 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 Scal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Herbert Arnaud Taylor, on behalf
of myself and the said Alexander Muirhead, 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 :-
With paper pulp is mixed a substance such as black lead (plumbago)
or precipitated metals, gold, silver, copper, or other good conducting
substance, by which a moderate conducting power is imparted to the
paper produced from the pulp, or by chemical processes conducting
materials may be precipitated in the body of the paper. The paper so
prepared is arranged between alternate layers of a di-electric, which may
consist of paper treated with paraffin, wax or shellac, of gutta percha, or
mica. In condensers or accumulators thus prepared the conducting
paper takes the place partly or in whole of the metallic sheets (tinfoil
or lead) hitherto generally employed.
To form the imitation telegraph line this conducting paper, insulated
as in the condenser by sheets of a di-electric material, is so arranged by
connecting a number of the sheets, either in continued or parallel circuit,
that the electrical properties of the telegraph line or cable are imitated,
so that uniformly throughout the imitation line the (conductive)
resistance bears the same ratio to the electrostatic capacity as the
resistance (either total or per unit of length) of the telegraph line or
cable bears to its electrostatic capacity.

page_text: Paper made as described above may be used in constructing standards
of high resistance.
In order that our said Invention may be most fully understood we
will proceed to describe more in detail the manner in which we prefer to
carry it into effect.
We obtain a paper which contains intimately intermixed with the
pulp a conducting powder, plumbago we prefer. The paper we have
used and which works well contains about 50 per cent. of plumbago;
it is of the substance of stout blotting paper, and we obtain it in sheets
about 11 x 18 inches, but other sizes of course may be obtained if
required. The plumbago is mixed with the paper pulp in the same way
as other powders have sometimes been introduced with a view to give
substance to the paper. When this paper is to be used in conjunction
with paraffin paper we apply, in order to render it less porous, a weak
solution of shellac in alcohol, either by dipping or brushing, but this is
unnecessary when shellaced paper is used for the insulator. We also
obtain sheets of a suitable di-electric. Paper saturated with paraffin
wax we employ by preference. We also obtain sheets of a material
which is a good conductor of electricity; we employ tinfoil by pre-
ference. We place these sheets the one on the other in the following
order:―

page_text: wider than the plumbago paper, so that they effectually prevent the
sheets of plumbago paper coming into contact the one with the other,
except at the margins, as already stated. The sheets of tinfoil are
smaller than the sheets of paraffin paper so as to ensure that they shall
be kept out of contact with the plumbago paper, but the sheets of tinfoil
or tongues projecting from them are allowed to come into contact the
one with the other at one or both sides, remote from the projecting
margins of the plumbago paper.
It is advisable to put the sheets together when the paraffin is hot, and
to press them between hot plates of metal from time to time as the
sheets are accumulated, so that the paraffin sheets may adhere closely
together all round, except where the projecting parts or tongues of the
tinfoil come between them. This completes the construction of one unit
or section of the artificial line or balancing apparatus.
To form a complete artificial line or balancing apparatus a number,
more or less considerable, of such units are combined the one with the
other by connecting their rivetted margins in such a way as to establish
a good electric communication between them, and when the instrument
is in use one end of the artificial line or balancing apparatus may be
connected with the transmitter and the other to earth, whilst the sheets
of tinfoil have a direct earth connection. This is the arrangement we
prefer when the cable has a direct connection with the transmitter and
with the receiving instrument; or if, as is now very usual, condensers
are interposed at both ends between the cable and the instruments, we
make similar arrangements in respect to the artificial or balancing line.
When the cable is worked on other systems the connections will be
varied to suit the particular system in use, as will be well understood by
electricians, the object being in all cases to assimilate as closely as
possible the conditions under which the actual and the imitation cable
are worked.
If we desire to make an artificial line or balancing apparatus to work
with an existing telegraph cable of which the resistance and capacity
are known we can so construct our unit as to represent both in resistance
and capacity a given length of the cable, and then it is only necessary to
couple up these units in continuous circuit to correspond to the entire
length of the cable, but in other cases it is convenient to make the units
with comparatively high resistance as compared with the capacity, and
then by arranging the units in parallel circuit a balancing arrangement

page_text: The construction of the balancing apparatus or imitation telegraph 1
line or cable to be used in duplex or other telegraphy.
Also of electric condensers and resistances with paper with which a
conducting material is incorporated, substantially as described.
In witness whereof, I, the said Herbert Arnaud Taylor, have here-
unto set my hand and seal, this Twenty-fourth day of August, 1
in the year of our Lord One thousand eight hundred and seventy-
five.