IMPROVEMENTS IN THE MEANS AND APPARATUS EMPLOYED INSULATING ELECTRO-TELEGRAPHIC OVERLAND LINE FOR SUSTAINING WIRES
Year: 1869

page_text: LETTERS PATENT to William Alexander Lyttle, of The Grove,
Hammersmith, in the County of Middlesex, Engineer, for the
Invention of IMPROVEMENTS IN THE MEANS AND APPARATUS EMPLOYED
INSULATING ELECTRO-TELEGRAPHIC OVERLAND LINE
FOR SUSTAINING
WIRES."
Sealed the 17th August 1869, and dated the 16th March 1869.
PROVISIONAL SPECIFICATION left by the said William Alexander
Lyttle at the Office of the Commissioners of Patents, with his
Petition, on the 16th March 1869.
I, WILLIAM ALEXANDER LYTTLE, of The Grove, Hammersmith, in the
County of Middlesex, Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE MEANS AND APPARATUS EMPLOYED FOR
SUSTAINING AND INSULATING ELECTRO-TELEGRAPHIC OVERLAND LINE WIRES," to
be as follows :-
I use enamelled iron either wrought or cast in forming the stems
which support. the "inverts" or other insulating caps such as are now
[Price 8d.]

page_text: employed; of course if such enamelled stems are properly insulated at
the end where they are cemented to the invert or or other insulator the
total increase of insulation realized by the enamelling of the iron will
depend on the length of the stem from the aforesaid cap to the point
where the surface of the stem comes in contact with the wood or iron of
the arm or post to which the enamelled stem is secured. At the latter
point it may be found desirable to wrap the stem with leather, felt, cloth,
or paper well saturated with india-rubber or other insulating solution,
and also to interpose an insulating washer between the nut screwed to
the lower end of the stem and the wood or iron of the arm or post. If
the latter precautions are adopted it may be found practicable, at least
on short lines, to dispense wholly with insulating caps, the top of each
enamelled stem being directly secured to the line wire without the
intervention of any cap by any of the plaus now in use for securing the
line wires to the insulators, or by the top of the stem being provided
with a clamping screw and transverse slot like those generally employed
in making the connexions of voltaic batteries when copper strips are
used instead of wires. The telegraph wire should when stretched be
inserted laterally or rather transversely into the slot, and a few turns of
the clamping screw would secure it against all risk of slipping. Before,
however, inserting the wire in the slot I prefer, especially in the case of
long lines, to wrap the wire with paper thoroughly saturated with india-
rubber or paraffine. That peculiar paper now well known to telegraph
engineers as cotton felt tape will answer the purpose admirably. The
plan best suited for wrapping the paper round the wire, when the paper
is not in the form of tape, is as follows:-Take a square sheet of the
paper and wrap it tightly round the wire, beginning at one of the corners
of the sheet and winding it so that the wire shall lie in a diagonal of the
sheet when half the sheet is wound; the opposite corner will thus come
to overlie that at which the folding commenced. A thin slip of zinc
may then be wound round the paper at this point, and at this point the
clamping screw or other fastening of the insulating stem should grip the
covered wire. The paper may then, if desired, be painted or varnished.
Another plan of employing the enamelled iron for the purpose of
insulation will in some circumstances, especially where each post has
many wires to carry, be found still more desirable. It is as follows:-
Make a square or circle of enamelled iron either tubular or solid, and of
any desired form of cross section, the size of the circle or square being

page_text: wires
То
such that, when it is bolted or otherwise secured to the telegraph post at
two diametrically or diagonally opposite points, it may be capabable of
carrying on its outer edge, at convenient distances apart, all the wires
required for the several lines. Before the iron is enamelled its outer
edge may be provided with notches or saddle-like projections at the
several points where the line wires are to lie, and at these points the line
may each be bound down either by being simply secured with
lapping wire to the enamelled iron, or by means of a saddle clamp with
one or more clamping screws. This clamp should embrace the inner or
under surface and the sides of the enamelled iron, and should then be
secured to the line wire. Wherever a screw is mentioned in this Speci-
fication a wedge or key may be made to answer equally well.
prevent the chipping of the enamel from pressure or friction an
intervening packing of leather, felt, paper, or cloth, saturated in some
waterproofing solution, should be used to separate the binding wire or
clamp from the enamelled iron. Of course, enamelled iron can also be
employed in the form of a simple cress arm or as a vertical bar on the
side of the post, or else the upper part of the post, if not its entire length,
may consist of enamelled iron. When the line wire is secured to the
enamelled iron arm, circle, or square, without the intervention of a pro-
jecting stem for each wire, the wire may be wrapped, if desired, with
insulating paper before being bound as already described, and it may
have an insulating saddle of pottery, glass, or any other of the substances
Dow used as insulators inserted between it and the enamelled iron.
Anything hard attached to enamelled iron had better be provided at
the point or surface of contact with some packing to prevent the enamel
being scaled off.
I do not confine myself to any particular description of enamel. The
enamel may be white or of any other colour, and that which possesses
the highest gloss is the best. A glaze or enamel liable to crack under
atmospheric changes of temperature will not answer, and the thinnest
coating of enamel will suffice if its surface forms an unbroken insulating
covering for the iron. The thinner the enamel the less liable it is to
crack under heat or cold. With some kinds of enamel it will be found
that two or more separate coats of very thin enamel laid on in succession
will give a more certainly uniform insulating covering than when all
the enamel is applied in a single coat.
When iron telegraph posts are required I prefer to construct them of

page_text: very thin tubular metal, and to ram the interior full of good hydraulic
cement or concrete to impart the requisite solidity and rigidity. Plaster
of Paris mixed into a thin pasty concrete with small gravel can be easily
poured into the post with the help of a funnel, and it quickly hardens
into a stoney mass.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Alexander Lyttle in the Great Seal Patent
Office on the 11th September 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ALEXANDER LYTTLE, of The Grove, Hammersmith, in the County of
Middlesex, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of March, in the year of
our Lord One thousand eight hundred and sixty-nine, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Alexander Lyttle, Her
special licence that I, the said William Alexander Lyttle, my executors,
administrators, and assigns, or such others as I, the said William
Alexander Lyttle, 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 Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
for "IMPROVEMENTS IN THE MEANS AND APPARATUS EMPLOYED POR SUSTAINING
AND INSULATING ELECTRO-TELEGRAPHIC OVERLAND LINE, WIRES," upon the
condition (amongst others) that I, the said William Alexander Lyttle,
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 William Alexander Lyttle, do hereby
declare the nature of the said Invention, and in what manner the same

page_text: is to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say:-
I use enamelled iron either wrought or cast in forming the stems
which support the "inverts" or other insulating caps such as are now
employed; of course,
if such enamelled stems are properly insulated at
the end where they are cemented to the invert or other insulator the
total increase of insulation realized by the enamelling of the iron will
depend on the length of the stem from the aforesaid cap to the point
where the surface of the stem comes in contact with the wood or iron of
the arm or post to which the enamelled stem is secured. At the latter
point it may be found desirable to wrap the stem with leather, felt,
cloth, or paper well saturated with india-rubber or other insulating
solution, and also to interpose an insulating washer between the nut
screwed to the lower end of the stem, and the wood or iron of the arm
or post. If the latter precautions are adopted it may be found practi-
cable, at least on short lines, to dispense wholly with insulating caps, the
top of each enamelled stem being directly secured to the line wire
without the intervention of any cap by any of the plans now in use for
securing the line wires to the insulators. Before, however, attaching the
wire I prefer, especially in the case of long lines, to wrap the wire with
paper thoroughly saturated with india-rubber or paraffine. That
peculiar paper now well known to telegraph engineers as cotton felt
tape will answer the purpose admirably. The plan best suited for
wrapping the paper round the wire when the paper is not in the form of
tape is as follows:-Take a square sheet of the paper and wrap it tightly
round the wire, beginning at one of the corners of the sheet and winding
it so that the wire shall lie in a diagonal of the sheet when half the
sheet is wound. The opposite corner will thus come to overlie that at
which the folding commenced. A thin slip of zinc may then be wound
round the paper at this point, and at this point the fastening of the
insulating stem should grip the covered wire. The paper may then, if
desired, be painted or varnished.
Another plan of employing the enamelled iron for the purpose of
insulation will in some circumstances, especially where each post has
many wires to carry, be found still more desirable; it is as follows:-
Make a square or circle of enamelled iron, either tubular or solid, and of
any desired form of cross section, the size of the circle or square being
such that, when it is bolted or otherwise secured to the telegraph post at

page_text: two diametrically or diagonally opposite points, it may be capable of
carrying on its outer edge, at convenient distances apart, all the wires
required for the several lines. Before the iron is enamelled its outer
edge may be provided with notches or saddle-like projections at the
several points where the line wires are to lie, aud at these points the
line wires may each be bound down either by being simply secured with
lapping wire to the enamelled iron, or by means of a saddle clamp with
one or more clamping screws. This clamp should embrace the inner or
under surface and the sides of the enamelled iron, and should then be
secured to the line wire. Instead of a screw a wedge or key may be
made to answer equally well. To prevent the chipping of the enamel
from pressure or friction an intervening packing of leather, felt, paper, or
cloth, saturated in some waterproofing solution, should always be used
to separate the binding wire or clamp from the enamelled iron. Of
course enamelled iron can also be employed in the form of a simple cross
arm or as a vertical bar on the side of the post, or else the upper part of
the post, if not its entire length, may consist of enamelled iron. It is
necessary, however, to have the upper part of the post perfectly insulated
from the remainder of the post. When the line wire is secured to the
enamelled iron arm, circle, or square without the intervention of a
projecting stem for each wire, the wire may be wrapped, if desired, with
insulating paper before being bound, as already described, and it may
have an insulating saddle of pottery, glass, or any other of the sub-
stances now used as insulators, inserted between it and the enamelled
iron.
Anything hard attached to enamelled iron had better always be
provided at the point or surface of contact with some packing to prevent
the enamel being scaled off.
I do not confine myself to any particular description of enamel.
The enamel may be white or of any other color, and that which
possesses the highest gloss is the best. A glaze or enamel liable to
crack under atmospheric changes of temperature will not answer, and
the thinnest coating of enamel will suffice if its surface forms an
unbroken insulating covering for the iron. The thinner the enamel the
less liable it is to crack under heat or cold. With some kinds of enamel
it will be found that two or more separate coats of very thin enamel laid
on in succession will give a more certainly uniform insulating covering
than when all the enamel is applied in a single coat.

page_text: When iron telegraph posts are required I prefer to construct them of
very thin tubular metal, and to ram the interior full of good hydraulic
cement or concrete to impart the requisite solidity and rigidity. Plaster
of Paris mixed into a thin pasty concrete with small gravel can be easily
poured into the post with the help of a funnel, and it quickly hardens
into a stony mass.
Having now described the nature of my Invention, and some of the
best means known to me for carrying the same into effect, I wish it to
be understood that what I claim is, the employment of glazed,
enamelled, or porcelain surfaced iron as an insulating supporter for
telegraphic wires, the enamelled iron being itself insulated by the
intervention of a separate non-conductor of electricity from the telegraph
line wire or wires, or from the post, or from both.
In witness whereof, I, the said William Alexander Lyttle, have
hereunto set my hand and seal, this 11th day of September, in
the year of our Lord One thousand eight hundred and sixty-
nine.