IMPROVEMENTS IN THE CONSTRUCTION OF CHANNELS OR COURSES SUITABLE FORM AND MATERIALS THROUGH WHICH WIRES TO BE USED FOR ELECTRICAL, MAGNETIC, TELEGRAPHIC AND TELEPHONIC PURPOSES MAY BE PASSED, SECURED AND PROTECTED AND ALSO WHEN NEEDED FOR INSULATING SUCH WIRES AND FOR OTHER ITSERIIL PURPOSE
Year: 1882

page_text: LETTERS PATENT to George Middleton Edwards of No 54 Gresham Street
OF
in the City of London EC Public Accountant, for an Invention of
IMPROVEMENTS IN THE CONSTRUCTION OF CHANNELS OR COURSES
SUITABLE FORM AND MATERIALS THROUGH WHICH WIRES TO BE USED FOR
ELECTRICAL, MAGNETIC, TELEGRAPHIC AND TELEPHONIC PURPOSES MAY BE
PASSED, SECURED AND PROTECTED AND ALSO WHEN NEEDED FOR INSULATING
SUCH WIRES AND FOR OTHER ITSERIIL PURPOSE
PROVISIONAL SPECIFICATION left by the said George Middleton Edwards
at the Office of the Commissioners of Patents on the 2nd August 1882.
GEORGE MIDDLETON EDWARDS of N° 54 Gresham Street, in the City of London,
"IMPROVEMENTS IN THE CONSTRUCTION OF CHANNELS OR COURSES OF SUITABLE
FORM AND MATERIALS THROUGH WHICH WIRES TO BE USED FOR ELECTRICAL,
MAGNETIC, TELEGRAPHIC AND TELEPHONIC PURPOSES MAY BE PASSED, SECURED
AND PROTECTED, AND ALSO WHEN NEEDED FOR INSULATING SUCH WIRES, AND
FOR OTHER USEFUL PURPOSES
"
My Invention has for its object the formation of Channels or Courses, through
which Wires for conveying the Electric current can be passed and which from
their character and the method pursued in their construction will afford increased
facilities for the testing and regulation of the electric current and the protection of
the wires.
For the purpose of my Invention, I use Sheet Iron or other Sheet Metal of
suitable strength and guage which has been previously crinilated or corrugated in
such form that each fold or corrugation shall present the form of a dovetail and bo
capable of retaining in its grip plastic materials such as Cements, Concretes,
Asphaltes or any other suitable material or composition, which, being inserted in a
soft or pliable condition, will set or harden and so be retained by the Sheet Metal
within and upon its dovetailed corrugations in such a manner as to cause the two
to net together as one under compression or tension.
These corrugated Sheets of Metal when rivetted or otherwise connected together
by the ends parallel to the corrugations, will become of sufficient length to permit
79

page_text: of their being curved around a moveable core of an oblate or lozenge form and be
thus formed into an Elliptical Tube or Channel, which can be lengthened to any
extent desirable by the insertion of the corrugated end of one tube within the
corrugations of another formed to receive it, and so make a good and well fitting
joint, the two joined ends being rivetted or fastened together if necessary
and the outside of the Tubes being encircled with Metal bands, if needful, for
stability.
These Tubes whilst in process of construction, will be sunk longitudinally in a
channel excavated to the requisite depth in a street or road or elsewhere and be
held in position whilst the portion of the channel unfilled by the Metal Tube is
flooded with cement or concrete, which will thereupon enter into the dovetailed
corrugations whose openings are on the outer face of the metal tubes and set and
harden therein, and thus hold the tubes firmly and form a construction of great
strength.
The interior of the Tunnel or Subway thus formed will have a grooved or
channelled metallic surface, every groove being in the shape of a dovetail open at
its narrow end.
These interior grooves will be filled with plastic materials around the surface of
the Tubes, only to the extent which may be desired to give strength and rigidity
to resist pressure from without, or the interior of the Subway may be
sustained by a hollow metal or timber core, in sections, or both systems may be
utilized in cases where the conduit of the wires may need such arrangement.
The height and breadth as also the form of these Channels or Subways may
differ as circumstances may demand, but they will advantageously be constructed
of sufficient height to allow of a man walking therein and of breadth enough to
admit of one person passing another without either coming into contact with the
wires.
My invention has also for its object, the insulation of the wires used for
conducting the Electric current by means of Insulators constructed in various
forms and materials, but with a dovetailed base for insertion into the metal grooves
before alluded to in the interior of the Subway.
By constructing these Insulators of a width sufficiently less than the opening of
the dovetailed groove to admit of their being inserted therein sideways, and after
insertion, turning them to an upright position within the groove they will be held
locked therein and be unable to be extracted until again turned sideways.
Increased facilities for the speedy fixing and unfixing of Insulators without any.
other fastening will be thus afforded.
I construct Man-holes or Doors set in Iron or other framework for ingress and
egress to and from the Subway, as part of the structure, and use stands of Slate
or other incombustible material therein for electrical purposes, for the support of
which the metal grooves above named will afford great facilities and for other
useful purposes incident to my Invention.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said George Middleton Edwards in the Great Seal Patent Office on the
2nd February 1883.
OF
GEORGE MIDDLETON EDWARDS of N° 54 Gresham Street in the City of London.
E.C. IMPROVEMENTS IN THE CONSTRUCTION OF CHANNELS OR COURSES
SUITABLE FORM AND MATERIALS, THROUGH WHICH WIRES TO BE USED FOR
ELECTRICAL, MAGNETIC, TELEGRAPHIC AND TELEPHONIC PURPOSES MAY BE
PASSED, SECURED AND PROTECTED, AND ALSO, WHEN NEEDED, FOR INSULATING
SUCH WIRES, AND FOR OTHER USEFUL PURPOSES.
My Invention has for its object the formation of Channels or Courses through
which Wires for conveying the Electric or other current can be passed, secured and
protected, such Channels or Courses being formed either beneath or on or above
the surface of the ground.
For the purpose of my Invention, I use Sheet Iron or other Sheet Metal of
suitable strength and guage, which has been previously corrugated in such form
that each fold or corrugation shall be in the form of a dovetail open at its narrow
end, to be capable of retaining in its grip plastic materials such as Cements,
Concretes, Asphaltes or any other suitable material or composition which, being
inserted in a soft or pliable condition, will set or harden and so be retained by the
Metal Sheet within and upon its corrugations and surfaces in such a manner as to
cause the two classes of materials, namely, Sheet Metal and Plastic Materials to act
together as one under compression.
These corrugated Sheets of Metal, when rivetted or fastened together or otherwise
connected by the ends parallel to the corrugations, will become of sufficient length
to permit of their being curved around a moveable core of an oblate or lozenge form,
and be thus formed into an Elliptical Tube or Channel, which can be lengthened
to any extent desirable by the insertion of the corrugated end of one Tube within
the corrugations of another formed to receive it, and so make a good and well
fitting joint, the two joined ends being rivetted or fastened together if necessary.
The method of constructing these Channels according to my Invention is as
follows.
First. To excavate a trench or channel in the earth of sufficient depth to permit
of the corrugated Metal Cylinders or Tubes being put together therein, by adding
Sheet to Sheet of corrugated Metal, in the manner before described, and fitting
them upon the above mentioned moveable core, which may, for convenience of
moving it forward as the work proceeds, be constructed in Sections and be screwed
together.
Secondly. To place bands of Hoop Iron or other metal around the outside surface
of the corrugated Metal Tubes thus formed, to cause them to fit close to tho
moveable core.
Thirdly. To fill in the whole space in the trench, left unfilled by the Tubes, with
Cement, Cement concretes or other suitable plastic materials and cause them to
sink into and fill up the open ends of the corrugations around the whole outer
circumference of the Tubes.
The effect thus caused, will be that the corrugated Metal Tubing will be held
firmly bedded or dovetailed in the Plastic Materials when the latter shall presently
set or harden.
These materials will then form a solid wall on each side of and in combination
with the metal Tube, and a strong foundation underneath it, the thickness of the
walls and of the foundation being regulated as may be necessary, according to the

page_text: nature of the ground and of the weight either of street traffic or otherwise, which
the Tubes or Subways may be subjected to..
The bulk of plastic materials above the corrugated Tubes may be shaped in any
form desired, but the arched form is advantageously employed.
If the corrugated Tubes are only partially embedded in the earth, or are placed
entirely above ground, the foregoing process of construction is modified only to the
extent which such deviation from the above description renders necessary tho use
of well known appliances for building up concrete walls. For the purpose of
ingress and egress to and from the Channel or Subway thus formed, and for
ventilation, I construct Man-holes or Doors set in metal or other frame work, as
part of the structure, the said Man-holes opening either directly above the crown
of the Subway or slanting downwards at the necessary angle when the entrance to
the Man-hole is on a footway, and the Subway to the right or left hand under the
street or roadway.
Although the Subways formed as herein described can be most advantageously
constructed in the elliptical form, that shape not only giving great strength and
height but occupying a comparatively small space relatively to its weight bearing
capabilities, my Invention has also for its object to afford increased facilities for
altering the form and dimensions of the Channels or Courses, to meet circumstances
under which the full size or any particular shape of the Channel would be either
inconvenient or inapplicable.
These facilities are afforded by the Tubes being easily forced into various con-
figurations cither of extension or reduction of diameter or of height, before the
plastic materials are inserted. Thus they can be made to assume a Cylindrical,
Elliptical, Square, Oblong or kindred forms without departing from the general
principle of their construction. Obstacles met with in what would be the direct
course of the Subway can, by my Invention, thus be avoided by altering its shapo
and combining in its construction some of the common and well known methods of
building, my Invention readily permitting of combination with Iron or other
metal tubes commonly used for the conduit of Wires for Electrical and other
purposes.
"
Thus, for instance, if it became necessary for the Subway to come to a dead stop
in consequence of having to pass through a Sewer or similar obstacle, the end of
the Subway could be blocked by Concrete or Masonry and the wires carried through
an Iron Pipe or several pipes, over, under or through the obstacle, and the Subway
would then again be enlarged to its required size. Whore necessary also it could
be carried over the obstacle above ground, as an arched tube full size.
The interior of the Channel or Subway thus formed will have a grooved or
channelled metallic surface, every groove being in the form of a dovetail about one
inch deep, open at its narrow end. These interior grooves I fill with plastic
materials around the surface of the Tubes, only to the extent which may be
necessary to give strength and rigidity to resist pressure from without, as it is
desirable to leave enough open grooved surface to hold mechanical contrivances for
supporting the Wires, or the Wires themselves in some cases. The interior of the
Subway may, if circumstances render it needful, be still further sustained or
strengtliened to resist pressure from without, by a hollow metal or timber core, in
sections, and the exposed metal can be protected from rust or oxidization by
various well known appliances.
The height and breadth of the Channels or Subways may differ as circum-
stances may demand but they are advantageously constructed of sufficient
height to allow of a man walking therein, and of breadth enough to admit
of one person passing another without either coming into contact with the Wires.
My Invention has also for its object the insulation of the wires used for con-
ducting the Electric current by known means of Insulators, constructed in various
forms and materials but with a dove-tailed or semi-dovetailed base, for insertion
into the metal grooves before alluded to as forming the inner face of the Channel
or Subway.

page_text: By constructing these Insulators of a width sufficiently less than the opening of
the dovetailed groove to admit of their being inserted therein sideways, and after
insertion turning them to an upright position within the groove, they will be held
locked therein and be unable to be extracted until again turned sideways.
Increased facilities for the speedy. fixing and unfixing of Insulators will be
afforded by this system of fixing them in dovetailed grooves. To give increased
area for the conduit and support of Wires used for Electric and other purposes and
for the purpose of straining the wires, I place in the interior of the Subway upright
posts or pillars of wood or other suitable material, which are utilized for the further
purpose of carrying wires in insulators fixed thereto, and of sustaining slabs or
stands of Slate or other incombustible material, one end of which will be in the
metal groove of the Subway or Channel and the other will be supported by these
uprights. By these means great facilities will be afforded for the conduit of a very
large number of Wires and for keeping wires used for different purposes apart from
each other, also for personal inspection of the Wires and insulation thereof, as well
as for rapid fixing and repairing of the Wires and Insulation, without the wear
and tear caused by the present system of dragging them through small iron pipes.
The corrugation of the Metal Sheets can be performed in various ways, but I
advantageously employ the system for which I have obtained Provisional Protection
under date of 5th December 1882 N° 5780.
With respect to the accompanying Drawings.
Figure 1. Represents one form of Insulators, as an illustration of the principle
adopted for fixing them in the metal grooves, A being the Insulator semi-dovetailed,
and B the wedge driven in to fix it securely in the Metal groove.
Figure II, is an end view of the same.
Figure 1II, is an end view of an elliptical form of Subway, A being the corrugated
Metal sheet, C the plastic materials set around and within the corrugations.
E the uprights for sustaining one end of the slabs for carrying the Wires, F the
Slabs, and D the boarding at the bottom of the Subway forming a moveable
walking surface.
Figure IV. Represents a Section of a Subway opened out to view shewing the
inner face of the corrugated Metal Sheet, C being the plastic materials set around
the Subway on the outside. H the cement or concrete filling in the inner surface of
the Subway. I being the cover to and G the Man-hole or ontrance to the Subway
from the pathway, and D the moveable boarding at the bottom of the Subway, for
a walking surface.
Having thus described the nature of my invention and in what manner the
same can be performed, I wish it to be understood that what I claim as my
Invention is, the general arrangements and combinations for the purposes and in
the modes herein before described and illustrated by my Drawings.
In Witness whereof I the said George Middleton Edwards have hereunto
set my hand and seal this Second day of February in the year of Our Lord
One thousand eight hundred and eighty three.
GEORGE MIDDLETON EDWARDS (L.S.)