IMPROVEMENTS IN INSULATORS FOR TELEGRAPH WIRES
Year: 1861

page_text: LETTERS PATENT to William Andrews, of Woburn Chambers, Henrietta
Street, Strand, and of 58, Threadneedle Street, in the City of London, for
the Invention of "IMPROVEMENTS IN INSULATORS FOR TELEGRAPH WIRES."
-Sealed the 12th September 1861, and dated the 21st March 1861.
PROVISIONAL SPECIFICATION left by the said William Andrews at the
Office of the Commissioners of Patents, with his Petition, on the 21st
March 1861.
I, WILLIAM ANDREWS, of Woburn Chambers, Henrietta Street, Strand, and
of 58, Threadneedle Street, in the City of London, do hereby declare the
nature of the Invention for "IMPROVEMENTS IN INSULATORS FOR TELEGRAPH
WIRES," to be as follows:-
This Invention has for its object improvements in insulators for telegraph
wires. For this purpose the wire is supported at the upper part of the insu-
lator, which is made by preference of porcelain, and all around the point of
support is formed a gutter or ditch; the exterior of the insulator forms the
outer side or wall of the ditch; and rises by preference as high as the point of
support of the wire, and is notched at two points opposite the one to the other
to allow the wire to pass to the point of support without touching the walls;
over the whole a cover, also by preference of porcelain, is placed, and cemented
down. At the bottom of the gutter or ditch holes are formed to allow any
water which may enter through the notches in the sides or walls to run out.
Price Sd 1

page_text: The insulator has a hole formed in it at its lower part to receive the end of an
iron stem or rod, on to which the insulator is fixed by cement. It is preferred
also to make the lower part of the insulator around the iron stem or rod bell-
shaped, as is usual, to assist the insulator. By this means an improved insu-
lation is obtained, as the sides of the gutter or ditch, being protected by the
cover, will not be liable to have water deposited or condensed upon them in
wet or damp weather. In place of fixing the wire on a point of support
surrounded by a gutter or ditch, the supporting stem or rod of metal which
carries the insulator may be cemented or fixed thereto, the said stem or rod
passing through a notch in the sides or walls, and a cover being used as before;
the wire is in this case either bound to the exterior or body of the insulator
or suspended from the lower part thereof, the point of suspension being, if
desired, surrounded by a bell-shaped projection from the bottom of the insu-
lator, as is common. Other arrangements may also be made so long as the
essential part of my Invention is employed, which is the interposing a gutter
or ditch fitted with a cover between the wire and the stem rod or other instru-
ment which carries the insulator. I also effect this purpose by taking an
insulator approximating to the ordinary form, and with the hole for the bolt
cast larger at the opening than at the end. Into this I cement the bolt. I
then pass the other end of the bolt through a hole in a centre piece, of porce-
lain or other material, surrounded by a ditch, as before described, so that,
however, the top of the exterior rim or bank of the ditch clears the top
insulator, and this 1 cement by the centre piece to the top or insulator of
ordinary form; I then fix thus or suspend the insulator by arranging the
ditch for the suspension form. By these means I always secure a dry shel-
tered chamber between the wire and the arm, or bracket, and post. I also
pass an inverted funnel-shaped piece of metal (sharp at bottom to be driven
into the wood of the arm) or of other material round the iron bolt, supporting
or suspending this or any form of insulator, and passing into the interior or
covered part of the insulator, but not in contact with it; and I bore holes in
the arm, as described in the Provisional Specification of my Patent dated the
18th October 1860 (No. 2548), of similar or other form, as the case may be,
and pour an insulating substance round the bolt; by this means the bolt is
insulated from the arm, and the funnel-shaped covering and the counter
sinking or boring of the. arm keep the motal bolt dry at its point of junction
with the insulating substance between it and the arm; and I cover the insu-
lator, where I use brittle materials, with a cover of the same form as the
insulator and hollowed like an ordinary insulator, which cover bears the wire.
This cover may be made of hard wood boiled in oil, or of metal partly filled

page_text: with a soft substance inside, or of other material; but I do not claim this as
part of my Invention, nor do I claim the insulated bolt, although I may use
that instead of the ordinary bolt.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Andrews in the Great Seal Patent Office on the
21st September 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ANDREWS, of Woburn Chambers, Henrietta Street, Strand, and of 58, Thread-
needle Street, in the City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of March, in the year of our Lord
One thousand eight hundred and sixty-one, in the twenty-fourth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Andrews, Her special licence that I, the said William
Andrews, my executors, administrators, and assigns, or such others as
I, the said William Andrews, 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 INSULATORS FOR TELEGRAPH WIBES," upon the condition
(amongst others) that I, the said William Andrews, my executors or adminis-
trators, 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 Andrews, 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 fol-
lowing statement thereof, that is to say :---
This Invention has for its object improvements in insulators for telegraph
wires. For this purpose the wire is supported at the upper part of the insu-
lator, which is made by preference of porcelain, and all around the point of
support is formed a gutter or ditch; the exterior of the insulator forms the
outer side or wall of the ditch, and rises by preference as high as the point of

page_text: support of the wire, and is notched at two points opposite the one to the other
to allow the wire to pass to the point of support without touching the walls;
over the whole a cover, also by preference of ebonite or porcelain, is placed
and cemented down. At the bottom of the gutter or ditch holes are formed
to allow any water which may enter through the notches in the sides or walls
to run out. The insulator has a hole formed in it at its lower part to receive
the end of an iron stem or rod, on to which the insulator is fixed by cement.
It is preferred also to make the lower part of the insulator around the iron
stem or rod bell-shaped, as is usual, to assist the insulation. By this means
an improved insulation is obtained, as the sides of the gutter or ditch, being
protected by the cover, will not be liable to have water deposited or condensed
upon them in wet or damp weather.
Figure 1 shews a transverse section of an insulator constructed as above
described; a being the point of support of the wire surrounded by a gutter or
ditch b, over which a cover c is cemented; the insulator is supported by the
iron stem or rod d from a wooden arm, as shewn, the stem or rod being
cemented into the bottom of the insulator. The insulator may, however, be
supported in any other convenient manner. In place of fixing the wire on a
point of support surrounded by a gutter or ditch, the supporting stem or rod
of metal which carries the insulator nray be cemented or fixed thereto, and be
surrounded by a gutter or ditch, a cover being used as before. The wire is
in this case either bound to the exterior or body of the insulator, or suspended
from the lower part thereof, the point of suspension being, if desired, surrounded
by a bell-shaped projection from the bottom of the insulator, as is common.
Figure 2 shews a section of an insulator thus constructed; in this Figure, a is
a hook for supporting the wire; this hook is cemented to the under side of the
insulator, but the wire may be otherwise supported from the insulator; b is
the rod by which the insulator is suspended from a wooden arm c, as shewn;
this rod is cemented to the upper part of the insulator; the part of the
insulator to which the rod b is connected is surrounded by a ditch d; over this
a cover e is placed, the rod b passing through a hole in the cover; the cover is
retained in its place by means of a nut screwing on a screw thread cut on the
rod b, a washer being placed between the nut and the cover; in addition cement
is also used to make the joint between the rod and the cover water-tight.
In place of the arrangements above described other arrangements may be
made, so long as the essential part of my Invention is employed, which is the
interposing a gutter or ditch fitted with a cover between the wire and the stem
rod or other instrument which carries the insulator. This object I also effect
by taking an insulator approximating to the ordinary form; into this I cement

page_text: the bolt; I then pass the other end of the bolt through a hole in a centre piece
of porcelain or other material surrounded by a ditch, as before described, so
that, however, the top of the exterior rim or bank of the ditch clears the top
insulator, and this I cement by the centre piece to the top or insulator of
ordinary form.
Figure 3 shews an insulator having a gutter or ditch combined with it, as
above described. a is an earthenware or porcelain insulator of the ordinary
form, having a notch at its top to receive a wire; into the interior of this
insular is cemented the piece b, also of earthenware or porcelain; this piece
is cemented, as shewn by the Drawing, on to the top of the rod or stem c; the
piece b has a gutter or ditch formed around it; the rim of this ditch does not,
however, touch the top insulator a; by this means a dry sheltered chamber is
secured between the wire and the arm d which carries the insulator.
Figure 4 shows another insulator combined with a gutter or ditch; the
exterior pari a of the insulator which supports the wire is in this case made of
ebonite, into this part the end of the stem or rod b is cemented; the upper
part of the rod is coated with ebonite, and is surrounded by a cup c, also of
ebonite, the rod passing through a hole in the bottom of the cup; the cup c is
cemented at its lower end to the ebonite covering of the rod b, and when so
cemented forms a ditch of insulating material around the rod. In place of
cementing a cup e to the ebonite covering of the rod, the cup may be made in
one piece with the covering.
The insulator shewn at Figure 5 is made of porcelain or earthenware, and
is supported on a rod or stem of like material, a gutter or ditch a being
formed around the rod or stem, as shewn.
Figure 6 shews a gutter or ditch combined with that description of insulator
where the wire is supported by a hook projecting from the under side of the
insulator. a is the hook for supporting the wire, the upper end of the stem of
which is cemented to the under side of the insulator, the insulator shewn in
the Drawing being made of porcelain. The stem of the hook is coated with
ebonite, and around the stem is formed a ditch or gutter of ebonite in like
manner to that shewn at Figure 4. I also pass an inverted funnel-shaped
piece of metal (sharp at bottom. to be driven into the wood of the arm) or of
other material round the iron bolt, supporting or suspending the above or any
other forms of insulators passing into the interior or covered part of the
insulator, but not in contact with it, and I bore holes in the arm as described
in the Specification of my Patent, dated the 18th October 1860 (No. 2548).
of similar or other form as the case may be, and pour an insulating substance
round the bolt. By this means the bolt is insulated from the arm, and the

page_text: funnel-shaped covering and the countersinking or boring of the arm keep the
metal bolt dry at its point of junction with the insulating substance between it
and the arm. This object may also be attained in the manner shewn at
Figure 7; this Figure shews a stem or rod supporting an insulator, which may
be of any suitable construction; the rod passes through a hole in a wooden
arm; it may also, if desired, be insulated from the arm by means of sulphur or
suitable cenient, as described in the Specification of the Patent above referred
to. Around the stem or bolt is a cone a, which I prefer to form of ebonite;
this cone is closed at the bottom, and the bolt passes through a hole in the
bottom. At the top of the cone is a hole, the diameter of which is greater
than the diameter of the bolt, so that a space is left between the stem or bolt
and the hole in the top of the cone through which it passes; the top of the
cone passes up into the insulator, so that its interior is kept dry: a washer is
placed between a collar on the stem or rod and the bottom of the cone, and
the washer is nipped between the cone and the collar by screwing up the screw
nut b.
I cover the insulator, when I use brittle materials, with a cover of the same
form as the insulator, and hollowed like an ordinary insulator, which cover
bears the wire. This cover may be made of hard wood boiled in oil, or of
metal partly filled with a soft substance inside, or of other material, but I do
not claim this as part of my Invention, nor do I claim the insulated bolt,
although I may use that instead of the ordinary bolt.
Figures 8, 9, and 10 shew different forms of insulators surrounded by covers
of hard wood boiled in oil, but to the making covers for insulators of this
material I lay no claim.
In witness whereof, I, the said William Andrews, have hereunto set my
hand and seal, this Twentieth day of September, in the year of our
Lord One thousand eight hundred and sixty-one.
W. ANDREWS. (L.S.)