IMPROVEMENTS IN FOG AND DANGER SIGNALS, AND IN THE METHOD OF FURNISHING SUCH SIGNALS TO RAILWAYS, CLEARING THEM AWAY
Year: 1871

page_text: LETTERS PATENT to Edward Keirby, of Vine Works, Rochdale, in the
County of Lancaster, Manufacturer of India-rubber Packing, for the
Invention of
IMPROVEMENTS IN FOG AND DANGER SIGNALS, AND IN THE
METHOD OF FURNISHING SUCH SIGNALS TO RAILWAYS, CLEARING THEM AWAY
Sealed the 14th July 1871, and dated the 19th January 1871.
COMPLETE SPECIFICATION filed by the said Edward Keirby at the
Office of the Commissioners of Patents, with his Petition and
Declaration, on the 19th January 1871, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
KEIRBY, of Vine Works, Rochdale, in the County of Lancaster, Manu-
facturer of India-rubber Packing, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS IN
FOG AND DANGER SIGNALS, AND IN THE METHOD OF FURNISHING SUCH SIGNALS TO
RAILWAYS, CLEARING THEM AWAY WHEN NOT USED, AND THE DEBRIS WHEN THEY
ARE DISCHARGED," and have petitioned Her Majesty to grant unto me,

page_text: my executors, administrators, and assigns, Her Royal Letters Patent for
the same, and have made solemn Declaration that I am the first and
true Inventor thereof, and that the same is not in use by any other
person or persons to the best of my knowledge and belief.
NOW KNOW YE, that I, the said Edward Keirby, do hereby declare
that the following Complete Specification, under my hand and seal, fully
describes and ascertains the nature of the said Invention, and in what
manner the same is to be performed, in and by the following statement,
that is to say:―
I remove a length of the common rail and place instead thereof a
broader and deeper rail made sufficient to receive one side of and to
strengthen a frame, which I prefer to make rectangular, so as to fasten
to the rail above mentioned and to a building fixed in the soil. Into
this frame I place an upright shaft in the middle thereof in suitable
bearings, so as to revolve casily, and in the bottom bearing thereof I
place an adjusting upright scrow, so as the shaft and its appurtenances
herein-after described may be adjusted in a convenient and accurate
manner. On the top of the before-mentioned shaft I fasten a plate truly
made, which fits accurately and easily a hollow plate, part of which is
the rail above mentioned; which I place so as its inner edge will be in
line with the inner line of the rails, but being broader its outer edge
projects beyond the outer edge of the line of rails. This broad inserted
rail, which, as above described, I substitute for the common rail, I hollow
where the plate occurs above described, so as it is level or flush with the
top of the line of rails. In the plate on the top of the upright shaft
just described I drill a hole sufficient to receive an explosion ball, the
top of which projects above the plate, so that the engine wheels in
passing over it will compress it and cause it to explode. To the plate I
impart motion for three purposes; firstly, to charge the plate with an
explosive ball; secondly, to place the charge underneath the engine
wheels; thirdly, to carry the debris of the exploded ball past the line of
rail so far that it may be dropped; fourthly, this last motion is also
used when the danger being past the explosion of the ball becomes
unnecessary, in this case it is simply moved clear of the rail entire for
future use.
To charge the plate I place on the top of the upright shaft
which carries the plate a bevil wheel which gears with another bevil on
a short horizontal shaft passing into the charge box or tube, having on
it a wheel or pulley having in its periphery a hole or hollow just deep

page_text: enough to receive an explosive ball. The wheels adjust and retain the
plate and this pulley, so that the pulley is charged with a fresh explosive
ball when the plate is discharging the debris of an exploded one, and
when the plate is in position to be charged the hollow of the pulley
is opposite the hole drilled in the plate. The reciprocating motion
necessary to effect the work is obtained from the signal lever worked in
the ordinary manner.
By the arrangement I am enabled to place an explosive ball` of
requisite power on a rail on which an engine in danger is passing,
and to give notice of such danger by its explosion to the engineer
thereof and to the people on the train from any station where danger
exists immediately and certainly without the necessity of any one
running along the line to give such notice, and to remove the ball if
the danger has passed before it has been necessary to use it. I also
make the cover of the balls used of a substance which drops easily
when exploded, as some well-known substances would adhere to the
hole.
And in order that my Invention may be more fully understood and
more readily carried into effect, I will now proceed to describe the same,
reference being had to the accompanying Drawings, in which Fig. 1 is
an elevation, Fig. 2 is a plan, Fig. 3 shows a detail of the pulley d for
feeding explosive balls one by one.
a is the rail I substitute for the common rail; b, b¹, are two frames,
which I fasten together by two cross bars 62, 63. The frames b, b¹, at
the top I fasten to the rail a by suitable bolts against a flexible material:
Through the bearings 6º, 6º, in the cross bars 62, 63, I pass the upright
shaft c, having the chain pulley c¹ on it below, and the plate c³ fastened
to it above, as also the bevil d² which gives motion to the bevil d³ on
the horizontal shaft d³, to which is also fastened the pulley d for receiving
and conveying the balls. The lower bearing 6 has a screw 66 in its
lower side, so as to be capable of adjustment. By means of this screw
I am enabled to adjust the shaft c, so as the plate c² is exactly clear of
the hollow in the rail in which it turns round. The upper cross bar 6³
I furnish with a hollow plate, the lower edge of which is in line with the
hollow in the rail which receives the plate c², so that when the frame is
bolted to the rail the plate c² turns in a hollow, by which it is completely
surrounded. I give the shaft c and the pulley and plate fastened thereon
with the bevils and shaft d², d³, and pulley d and done half revolution,

page_text: and I drill the hole in the plate c² so that it is over the rail or in mid
travel when the ball is to be exploded, see Fig. 2. When it is charged
with ball it is at one end of its travel, and the pulley d has its hollow d¹
immediately over it, and when at the other end of its travel its hole
corresponds with the hole in the cross bar by, which the debris are
discharged (dotted in Fig. 2). Non-used balls are not discharged, but
merely moved past the edge of the rail for future use. In this position
also the hole or hollow d in the pulley d receives a ball from those
placed in position for use in the charge box or tube e. To turn the
pulley d one-half revolution, so as to accord with the plate and chain
wheel described, I make the bevils d², d³, of equal sizes. To the
pulley c¹ I fasten the chain ƒ by means of the set screw f¹, and conduct
it over the guide pulleys f², f³, on one side, and f', f³, on the other to
the signal lever or pulley h at any convenient. distance, so that the lever
at one side charges the plate c² at mid travel, or when upright places the
ball in position for explosion, and at the other discharges the debris, or
shifts the non-used ball, as the case may be, and at the same time the
pulley d by the hollow d' receives a fresh ball to be placed on the plate c³
for a future explosion. To enable me to move the pulley d to any
distance I take away the wheel driving by the bevils d² and d³, and in
place thereof I substitute chain driving, as shown in Fig. 4, Sheet 2.
The pulley d and case being made as in the former view, but the tube
leading from it to the plate being longer the pulley is farther removed
from the rails. On the end of the shaft d³ I fasten the chain pulley do,
which I connect to the hand signal pulleys or levers by an independant
chain or chains. For this purpose I place two large hand signal
pulleys h, h¹, of which the pulley h is connected, as in the Fig. 2, with
the chain pulley c', and the pulley / connected by another chain to the
pulley do on the shaft do to which the pulley d is affixed. By means of
this chain and pulley I am enabled to shift the position of the pulley d,
and so to keep it perfectly clear of the line of rails, whilst still fulfilling
the conditions maintained in my former Figure, as shown with reference
to Sheet 1, Fig 2.
The next part of my Invention refers to the formation of the fog
signal itself, see Fig. 5, Sheet 2. In this I place in the centre of the
ball a spherical core of wood, in which I fasten a series of studs which
receive a series of percussion caps. Around these caps and within an
outer shell I place a portion of gunpowder, so that when the outer shell

page_text: is compressed the caps explode, and the signal also gives its report to a
passing train. The core above described may be either wood or metal,
but if made of metal I elect to make the core of hollow material. It is
obvious by the above Drawing and description that either the pulleys h
and or the signal lever itself may be carried to the distance required
by the position of the signal box; but I prefer that the parts remain as
arranged and shown, and the connection to the signal box should be by
independant chains, weight, and lever, and that the working chains j, j',
(Fig. 4, Sheet 2,) should not be altered, as thereby the position of
explosion might be unconsciously tampered with. I prefer to use the
weight as a plumb-bob to keep the ball in position for explosion.
Having now described the nature of my Invention, and the manner
in which it is to be performed, I declare that I claim as secured to me
thereby,-
Firstly. The plate c³, described and shown, by which an explosive ball
is received and carried definitely for explosion under the engine wheels.
Secondly. The method described and shown by which explosive balls
are formed.
Thirdly. The pulley d and its hollow d³, by which an explosive ball is
received from a tube or charge box e and conveyed to the plate c³.
Fourthly. The definite manner in which balls exploded have the
debris carried away, or unused balls are set on one side of the rail
for future usc.
In witness whereof, I, the said Edward Keirby, have hercunto set
my hand and seal, this Seventeenth day of January One thousand
eight hundred and seventy-one.