Improvements in Electric Telegraph and Telephone Conductors and in the Means of Insulating, Laying, Uniting, and Securing the same.
Year: 1887

page_text: Date of Application, 25th Jan., 1887.
Complete Left, 30th Mar., 1887.
Complete Accepted, 6th May, 1887.
PROVISIONAL SPECIFICATION.
Improvements in Electric Telegraph and Telephone Conductors and
in the Means of Insulating, Laying, Uniting, and Securing the
same.
I, DONALD NICOLL of Buckingham Street, Strand in the City of Westminster, Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to certain improvements in electric conductors to be mainly
used as underground lines and in the means or method of insulating, laying, uniting
and securing them when laid, more particularly in thickly populated towns.
The conductors may be first prepared in the manner or manners described in
my former Patents dated Feb. 15th 1866 No. 480, March 11th 1867 No. 694 and
August 31st 1867 No. 2480 but I prefer to take wires covered in the usual way,
and in order further to insulate the same, and to protect their gutta percha or other
covering from decomposition, I twist in a spiral form, tape as it passes from a bath of
a molten compound which for easy reference I will call Nicoll's insulating compound;
I prepare this compound mainly from bitumen, chiefly obtained from Trinidad W.I.
that is to say, after the bitumen has been there made free from earthy matter or other
impurity (when it is known as "épurée" of Trinidad pitch), I add to 75 parts by
weight thereof 25 parts by weight of a substance now known as "cotton foots pitch,"
being the residuum or waste produced in the manufacture of cake, or cattle food
from cotton seeds. I find the introduction of this substance in combination with the
épurée to be a great improvement as diminishing the brittleness of épurée and its
consequent liability to be damaged in transit.
Before laying the conductors I usually form, two, four or more into a cable,
by passing round them a covering of tape saturated or covered with the said Nicoll's
insulating compound.
For laying and securing these conductors or cables in crowded districts I chiefly
use the edge of footways or pavements where I place cases or hollow curbs of cast iron
of an inverted trough shape, the upper surface of which is formed with projections"
that improve the footing for passengers and allow water to better drain therefrom
into gutters or gullies. These cases or hollow curbs are formed in lengths so as to
dovetail into each other when laid as a covering over a continuous line of insulated
conductors or wires.
Before placing the insulated wires or cables beneath the said dovetailed cases or
hollow curbs I usually lay a flooring of concrete in a trench formed for their reception
beneath the same, with perforations therein beneath which I place drain pipes to
provide for accidental flooding of the said cases or hollow curbs.
In order properly to lay and unite lengths of insulated wires before covering or

page_text: securing same
prepare of glass, earthenware or of some suitable material separators
to be used for a similar purpose to that set forth in one or more of the specifications
of my patents hereinbefore referred to, the said separators where there described as of a
dise form and were used for keeping wires equidistant from each other by threading
these through perforations in the said discs.
According to my present improvements I employ for this purpose oblong or square
blocks or slabs formed of any suitable substance but by preference of Victoria stone
these slabs or blocks have upon an upper and a lower surface indentations or grooves
which I coat with Nicoll's insulating compound before mentioned and in each of
these I lay a length of wire or cable placed in a position to be ultimately covered with
the cases or hollow curbs herein before described and when the lengths of insulated
wire are placed in the said indentations I place over same a corresponding block or
slab and so continue to build up layer upon layer of wires or cables as may be required
to be laid. I then place over the said layers of wires or cables the several lengths of
cases or hollow curbs which in dovetailing into each other require but little extraneous
support or surrounding concrete in order to form footway or pavement curbs as
capable to resist the percussion of cartwheels as the granite usually used for curbing
purposes.
These cases or hollow curbs it should be observed can with case be lifted clear from
each other so as to expose the several wires or cables for their inspection or repair or
for occasionally testing their insulation, and this can be effected at any desired point
and further to facilitate these latter purposes I employ the method of forming the
junction of the conductors described in one or more of the Specifications of my
patents hereinbefore mentioned which junction I then cover by means of a capsule of
gutta percha.
The junction is by preference made by forming a helical twist at the sharpened end
of the one length of wire and I insert the sharpened end of the other wire into the
said twist; the capsule is hermetically sealed up and joined to the cover of the wire
or cable by blowpipe heat, from a wax-light or other torch flame, when this is done,
I twist over the gutta-percha capsule the tape covered with the beforementioned
Nicoll's insulating compound which adheres thereto. The main advantages derived
from these methods are the diminished liability of damage by friction in the course of
laying, testing, and repairing conductors in crowded thoroughfares.
The cases or curbs, can be so formed that they may make the conductors serve for
any bend, or angle, and under, or over, any obstruction; the foregoing is a description
of the methods I propose to use in thickly populated districts but in rural districts,
and along railways I propose to dispense with the iron kerbs and to use only blocks of
the Nicoll's insulating compound for covering wires, or to lay same in tubes or semi
tubes in rigid sections, in trenches, and in any of the methods described in my
former patents with the like object.
I do not limit myself to the exact proportions of each of the substances forming
the Nicoll's insulating compound herein before mentioned because I have found in
practice, that the brittleness of the one ingredient, and the pliability of the other will
occasionally vary, and in making a bath for their combination in a molten state, I use
by preference a steam jacketted cauldron, and of sufficient length to serve for dragging
tape or covered wires through the heated compound, so as to avoid charring the fibre
intended to assist in the insulation of wires; for many purposes I also cover the wires
with the Nicoll's insulating compound alone and by mixing tar with the said com-
pound in a heated condition, I can provide for the cases of iron or wood used for the
foregoing purposes, a strong preservative coating against rust or decay.
I also prefer to crush up the two substances herein before described, and roll them
together before placing them in the bath herewith described.
1 1
1007
ABEL & IMRAY,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Electric Telegraph and Telephone Conductors and
in the Means of Insulating, Laying, Uniting, and Securing the
same.
I, DONALD NICOLL, of Buckingham Street Strand in the City of Westminster
Civil Engineer, do hereby delare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by the
following statement:―
This invention relates to certain improvements in electric conductors to be mainly
used as underground lines for electric purposes and in the means or method of laying,
insulating, uniting and securing them, more particularly in thickly populated towns.
The conductors may be first prepared in the manner or manners described in my
former Patents dated February 15th, 1866, No. 480, March 11th 1867, No. 694 and
August 31st 1867 No. 2480, but I prefer to take, for crowded thoroughfares, wires
covered in the usual way, and, in order further to insulate the same, and to protect
gutta percha or other coverings from decomposition, I twist in a helical form tape or
paper as such may pass in the form of a ribbon from a bath of a molten compound,
which, for easy reference I will call Nicoll's insulating compound. I produce the
compound from bitumen, chiefly obtained from Trinidad, W.I., that is to say, after
the bitumen has been there made free from earthy matter or other impurity (when it
is known as épurée of Trinidad pitch) I add to 75 parts by weight thereof 25 parts
by weight of a substance commonly known as cotton foots pitch being the residuum
or waste produced in the manufacture of cake, or cattle food from cotton seed. I find
the introduction of this substance in combination with the épurée to be a great
improvement as diminishing the brittleness of épurée and its consequent liability to
be damaged by percussion or in transit.
Before laying the conductors 1 usually form five or more into a cable, by passing
round a covering of tape or paper saturated or covered with the said Nicoll's insulating
compound.
For laying and securing these conductors or cables in crowded districts I chiefly
use the edge of footways or pavements where I place cases or hollow kerbs of cast
iron or steel of an inverted trough shape, the upper surfaces of which are formed with
projections that improve the footing for passengers and allow water to better drain
therefrom into gutters or gullies. These cases or hollow kerbs are formed in lengths,
so as to dovetail into and lap over each other when laid as a covering over a continuous
line of insulated conductors or wires; between the said laps or dovetailed parts, I, at
the time of laying the cases or hollow kerbs, apply the molten compound. The said
cases or hollow kerbs have a downward perforation next the roadway, which will allow
gas or foul air to escape.
Before placing the wires or cables beneath the said dovetailed cases or hollow kerbs,
I usually lay a flooring of concrete in a trench formed for their reception beneath the

page_text: same, WILD perforations therein, beneath which I place drain pipes to provide for
accidental flooding of the said cases or hollow kerbs.
In order properly to lay and unite lengths of insulated wires before covering or
securing same prepare, of glass, earthenware or of some suitable material, separators
to be used for a similar purpose to that set forth in one or more of the Specifications
of my Patents hereinbefore referred to the separators are there described as of a
dise form to be used for keeping wires equidistant from each other by threading them
through perforations in the said discs.
According to my present invention I employ for this purpose oblong or square
bricks, blocks or slabs, formed of any suitable substance, but, by preference, of
Victoria or ordinary glazed stoneware. These bricks, slabs or blocks have upon an
upper and a lower surface indentations or grooves which I coat or partially fill with
the Nicoll's insulating compound before mentioned alone or in combination with
grease or other substances used by me for insulating purposes and, in each of the said
indentations, I lay a length of wire or cable placed in a position to be ultimately
covered with the cases or hollow kerbs hereinbefore described, and when the lengthis
of insulated wire are placed in the said indentations, I place over same a corresponding
block or slab and so continue to build up layer upon layer of wires or cables in
number as may be required to be laid.
These blocks or slabs, for passing through swampy or wet land. I prefer to make in
long lengths, and I prepare, near to their edges and centres. ridges and furrows, the
furrows allowing the ridges to fit loosely into them so that they may receive a small
quantity of the aforesaid compound and to hold firm the ridged part of the blocks
when placed therein, and which then completely enclose the cables or wires herein
before described, and in such instances I prefer to embed the said cables or wires
in grease, alone or in combination with other substances described in this and my
previous Patents for the like object, so that if a settlement of the blocks or their
foundation should ensue, the insulation of the cables or wires is not effected, as
the grease or softened compound will not crack. I also make the slabs or blocks
to fill up the entire space within cases or kerbs in which they may be placed,
especially where gas or foul air is likely to accumulate, and when these blocks or
slabs are laid in places where much traffic does not exist, I do not require to use cases
or kerbs but can use open trenches 1,000 feet or more in length and lay the blocks
or slabs continuously and in the notches I lay the said wires or cables embedded and
insulated as may require; they are then covered with further layers of blocks or
slabs to contain wires or cables in any required number and as before described.
Lengths of wires of 1,000 feet or more, I first insulate by drawing through
the aforesaid bath containing my compound, and I then cover them with any
suitable fibrous substance by a plaiting machine of the kind set forth in my
patent No. 2480, 31st August 1867, but as an improvement on the process then used
by me I now cause the wires, as they come from the bath of molien compound, to
pass through a chamber kept at a temperature not exceeding 50° Fahrenheit so that
the compound is rapidly cooled into a plastic condition, and may thus be easily made
to surround equally the wire and to a given gauge; after this is done, the insulated
wire passes to another chamber which is kept at a temperature of noi less than
80° Fahrenheit, and there it is plaited over by the machine hereinbefore described, and
as a further improvement upon that process, I use fibres, by preference jute,
previously heated as much as possible, (i.e. without becoming charred), and thus the
plaiting becomes firmly attached to the compound, and further serves to secure the
insulation of the wires. I then pass them, while still warm, over a drum, measuring
by preference three feet in diameter, and previous to uncoiling same therefrom,
I cause the coil to be heated by any suitable means, especially in cold weather,
and in this condition it is ready in any length for comparatively temporary use,
and without requiring further protection will serve for a long period beneath the
surface, and in hot climates it will resist the white ani or other destructive insects,
which object to bitumenous substances. The wires thus secured are specially adapted

page_text: for following the march of an army and to keep up
or base of operations.
ommunication with the seaboard
In crowded thoroughfares I place over the said blocks holding or supporting layers
of wires or cables, the several lengths of cases or hollow kerbs, which, in dovetailing
into and overlapping each other, require but little extraneous support or surrounding
concrete, in order to form footway or pavement kerbs as capable to resist the
percussion of cartwheels as the granite usually used for kerbing purposes.
These cases or hollow kerbs, it should be observed, can with ease be lifted clear
from each other so as to expose the several wires or cables for their inspection
or repair, or for occasionally testing their insulation, and this can be effected at
any desired point and further to facilitate these latter purposes I employ the
method of forming the junction of the conductors described in one or more of the
Specifications to my patents herein before mentioned, which junction I then cover
by means of a capsule or ribbon of gutta percha, but before using the gutta
percha I prefer to cover the junctions with thin metal, to prevent the said gutta
percha interfering with the insulation of the wires.
The junction, has been, by preference, hitherto made by forming a helical twist at
the sharpened end of the one length of wire and I have inserted the sharpened
or tapered end of the other wire into the said twist but I now improve thereon by
twisting a short length of wire over the junction so as to bring the two aforesaid
points of junction into closer contact and one end of the short length of wire,
when necessary, 1 partially uncoil so that it may serve as a branch conductor
for telegraphic, telephonic, or other electrical conduit to any dwelling or other
object. The capsule or ribbon of gutta percha which I usually apply at points of
junction is then scaled up and joined to the cover of the wire or cable by blow
pipe heat or from a wax light or other torch flame, and when this is done, I
iwist over the gutta percha slips tape or paper covered with the before mentioned
Nicoll's insulating compound, and which adheres thereto.
The main advantages derived from the use of the cases or hollow kerbs above
described is the diminished liability of damage by friction in the course of laying,
testing, repairing and to connect or disconnect branch services to or from conductors
in crowded thoroughfares..
The cases or kerbs can be so formed that they may make the conductors serve
for any bend or angle or to pass under or over any obstruction.
The foregoing is a description of the methods I propose to use in thickly
populated districts, but in rural districts and along railways I propose to dispense
with the iron kerbs and to use only blocks of the Nicoll's insulating compound
for covering wires or to lay same in tubes or semi tubes in rigid sections, or to
cover the same with glass or earthenware, or to lay the same in trenches in any
of the methods described in my former Patents. with the like objects, but with
the several improvements for junction or service wholly or in part as herein
set forth.
I do not limit myself to the exact proportions of the substances forming the
Nicoll's insulating compound hereinbefore mentioned, because I have found in
practice that their brittleness and pliability will, in the course of manufacture,
occasionally vary.
In making a bath for their combination in a molten state, I use, by preference,
a steam jacketted bath, and of sufficient length to serve for dragging tape, paper
or fibre covered wires through the heated compound, or for dipping same in
suitable lengths; for many purposes I also cover the wires with Nicoll's insulating
compound alone, that is to say, without the intervention of gutta percha or
any other covering, also by mixing tar, or sand with the said compound in a
heated condition I can provide for the cases of iron or wood used for the foregoing
purposes a strong preservative coating against rust or decay. I also cover lead
piping with this preparation or with tape or paper coated with the compound. I
prefer to use leaden piping so covered for the purposes of conveying conductors into

page_text: dwellings as the means of protection against fire, or of persons from injury by any
accidental exposure of the said conductors when strongly charged with a current of
electricity, especially for illuminating purposes. Moreover the lead can thus better
serve for cutting off communication.
As a further improvement of the method described in one of my former Patents
whereby strands of wire are paid off from a drum upon a layer of insulating compound,
I now cause the said wires, in the course of being so paid off, to be thoroughly heated
so that they may be more readily embedded into the insulating compound.
Fig. 1 of the accompanying drawings shows a plan, Fig. 2 shews a sectional plan,
and Fig. 3 a cross-section of my above described arrangement of cases or hollow kerbs
containing electrical conductors.
The hollow cast iron or steel cases or kerbs A A A are laid at the edge of the foot
pavement B, flush therewith, with a grooved upper surface, and an outward inclination,
so that water will run over them into the gutter C of the roadway. The kerbs are
made in suitable lengths for convenient handling, and have apertures as shewn at K,
Fig. 3, for ventilation, and there may be provided at intervals a short length such
as A, that may be readily removed, by preference situated at the point where the
junction of the conductors are, so that these can be readily examined.
The ends of the lengths are, by preference, made with bevelled edged projections a a
dovetailing into corresponding notches, (also with bevelled edges,) in the other
lengths.
The base D on which the kerbs rest is of concrete or other suitable material in
which may be embedded a drain pipe. E for carrying off any water thai may drain
into the cases or kerbs. Upon the base D are placed the supports for the conductors
consisting of blocks or slabs shewn separately at Figs. 4 and 5, fitting over each
other and having notches in their meeting surfaces, forming together holes through
which the conductors G pass as shown.
By this arrangement the conductors are readily laid in position in the kerbs or
removed therefrom without having to be drawn through manholes.
For better holding the several blocks in position one upon the other, I prefer to
form projecting beads or ridges on the one side of each block and corresponding
grooves on the opposite side, as shewn, so that the beads on the one block will fit into
the grooves of the other when placed upon each other. Also, when such blocks are
made of greater length so as to fit closely end to end when they are used for entirely
enclosing the conductors as previously described, I form similar projections and
grooves on the vertical meeting faces of the block, as indicated at Figs. 5, 5 and 5,
the grooves being made somewhat larger than the projections, so that waterproof
compound may be introduced between the two to form a water tight joint.
Figs. 6, 7 and 8 shew the mode of forming the joints of the conductors which I
prefer to employ. The end of the one length H is formed with a helical twist of such
a size that the tapered straight end of the other length I will fit into it. tightly when
inserted as shown at Fig. 7, after which the joint is bound round with thin wire as at
Fig. 8, and is then covered with thin sheet metal pressed thereon in the manner
described in my before mentioned patents, and it is further covered by a gutta percha
ribbon or capsule. At certain intervals in the length of the conductors provide
thereon branch wires J, which I attach at the joints of the conductors in the manner
indicated at Fig. 9 namely by twisting the end of the branch wire round the straight
end I, in the spaces between the coil of the twisted end H so as to be in contact with
the coils and with the straight tapered end, the branch wire, suitably insulated, being
passed through a hole in the inner side of the kerb and led under ground to any
house or locality where a communication with the conductor is desired to be
established.
By preference I provide each joint with such additional coil of wire which is twisted
on some distance beyond the joint so that when a branch conductor is to be established
at any point, this is readily and quickly done by simply uncoiling the extended end of
such additional wire.
.

page_text: Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed I declare that what I claim is :-
1. The use for protecting electrical conductors of a compound consisting of pure
bitumen mixed with cotton foots pitch, substantially as herein described.
2. Constructing conduits for the electrical conductors of hollow kerbs of an inverted
trough form substantially as herein described.
3. The method of laying electrical conductors by fixing them in or by suspending
them on supports or separators formed of notched slabs or blocks placed one above the
other so that the meeting notches form holes through which the conductors pass, and
then, when needful, by enclosing them by means of hollow kerbs of an inverted
trough shape substantially as herein described.
4. Constructing insulating supports or separators for electrical conductors of notched
slabs or blocks placed one above the other so that the meeting notches form holes
through which the conductors are passed substantially as herein described.
5. Constructing joints for electrical conducting wires of a helically coiled end of
wire into the coils of which a straight tapered end of wire is introduced so as to fit
tightly therein, a separate length of wire being then coiled round the straight wire in
the spaces between the convolutions of the first coil, so that the one end of such length
of wire may serve to establish a branch service when required, substantially as herein
described.
ABEL & IMRAY,
Agents for the Applicant.