IMPROVED SAFETY APPARATUS FOR RAILWAY TRAINS
Year: 1873

page_text: LETTERS PATENT to William Thomas Cassel Pratt, of Lansdown
Place, Newport, in the County of Monmouth, for the Invention of
"IMPROVED SAFETY APPARATUS FOR RAILWAY TRAINS."
Sealed the 22nd May 1874, and dated the 29th November 1873.
PROVISIONAL SPECIFICATION left by the said William Thomas
Cassel Pratt at the Office of the Commissioners of Patents, with his
Petition, on the 29th November 1873.
I, WILLIAM THOMAS CASSEL PRATT, of Lansdown Place, Newport, in
the County of Monmouth, do hereby declare the nature of the said
Invention for "IMPROVED SAFETY APPARATUS FOR RAILWAY TRAINS," to be as
follows:-
This apparatus is intended to supersede the use of fog or detonating
signals, which so frequently through damp and other causes fail to act
as a timely warning to the driver of an approaching train when in thick
and foggy weather the danger signal may not be visible to him. It
consists of an arrangement by which the whistle on the engine is caused
to sound by means of a wire being severed when coming into contact

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Thomas Cassel Pratt in the Great Seal
Patent Office on the 29th May 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
THOMAS CASSEL PRATT, of Lansdown Place, Newport, in the County of
Monmouth, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-ninth day of November, in the
year of our Lord One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said William Thomas Cassel
Pratt, Her special licence that I, the said William Thomas Cassel
Pratt, my executors, administrators, and assigns, or such others as I,
the said William Thomas Cassel Pratt, 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 "IMPROVED SAFETY APPARATUS FOR
RAILWAY TRAINS," upon the condition (amongst others) that I, the said
William Thomas Cassel Pratt, 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 Thomas Cassel Pratt, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, reference being had to the
Drawings hereunto annexed, that is to say:-
This apparatus is intended to supersede the use of fog or detonating
signals, which so frequently through damp and other causes fail to act
as a timely warning to the driver of an approaching train, when in thick
and foggy weather the danger signal may not be visible to him. It

page_text: consists of an arrangement by which the whistle on the engine is caused
to sound, by means of a wire being severed or drawn out from a holder
when coming into contact with a blade placed alongside the rails on the
permanent way. The moment this wire through the momentum of the
train has been cut or drawn from its holder a cock placed on the top of
the fire-box is opened by an arrangement of rods and levers to admit
steam to the whistle which will go on sounding until the severed or
drawn wire has been replaced by a fresh one or the cock turned off.
The readjustment of a fresh wire can be done by the driver without
the least inconvenience or loss of time from the foot plate, and while the
engine is in motion; he has only to pull a rod or chain attached to the
actuating lever which rests on the wire, but falls down directly the
latter is cut or drawn out of its holder in order to bring the said lever
into a perpendicular position so as to clear the fresh wire which is
dropped down, a suitable guide made of iron or otherwise, and fixed
on the trailing end of the engine between the footstep plates. When'
this guide is placed on the outside of the buffer plate, as may be
necessary in some cases, the buffer plate should have two projecting
pieces placed at the same distance from the centre as the buffers on the
tender, to prevent the latter from coming into contact with the
apparatus.
The blades on the permanent way are placed at such a distance from
the signal box as that the ordinary danger light (which is to be used in
conjunction with the apparatus) can be seen in clear weather. When
not used these blades will be held down by rods or wires worked from_
the signal box, and they only assume a perpendicular position for the
cutting or withdrawal of the wire in the event of the said rods being
slackened. Separate blades independent of those worked from the
signal box can be employed.
First. Near to stations for the protection of the trains while there in
case of mistake being made by the signalman.
Second. Near to places of shunting to be used by the guard to protect
the train he is shunting.
Third. Near to level crossings and bridges where the blades could
be caused to act simultaneously with the opening and closing in case of
neglect on the part of the attendant, and in general in such places along
the line where it may be deemed necessary to use them.

page_text: The whistle is so arranged as to admit of its being used also by the
driver in the ordinary way independent of its functions connected with
this apparatus.
The Invention will be well understood by reference to the accom-
panying Sheet of Drawings in which Figure 1 is a side view of the
fire-box end of a locomotive, and Figure 2 a face view of the same end
with my patented apparatus applied thereto.
a is the foot plate of an engine, to either side of which is fitted a
vertical T iron 6 forming one of two guide pieces down which a short
length of wire c can be dropped, after a lever d has been drawn back to
permit the wire to do so and to take up a position for the lower end of
the lever d to bear upon or against to hold the lever back; e is another
vertical T iron as a guide and holder for the wire which also takes into
it when in a horizontal position across the gap between the two guide
irons. The lever d is centred at fand has a handle at its upper end
by which it can be readily moved when a fresh wire has to be dropped
or fitted in the guide irons. The lower end of the lever d is weighted
at h, which, when the wire is removed from any cause drops and compels
the upper portion of the lever to fall forward or backward according to
the fitting of the lever on the pin f, and thus draws a lever rod or wire i
whose opposite end is connected to one arm of a bell crank j, the other
arm having also a rod, lever, or wire k attached to the handle of a
whistle m, so that the steam passage is opened and the whistle sounded,
the sounding going on for any length of time unless closed by the driver
or fireman in charge. The wire c is arranged in the lower part of the
guide irons b, e, and is struck by a blade n which may either sever the
wire c or only draw it out from the guide irons, the blade n being upon
a cross rod p in connection with the signal pull, and raised into a vertical
position when the pull is intended to set the signal at danger, and to
assume a horizontal position when the signal (semaphore or lamp) is
shifted to "all clear," in which case the engine would pass on without
affecting the wire.
It will be understood that the wire may be nipped at one end by the
guide, say the inside one, so that the other end of it which is only held
in place by the pressure of the lever d to ensure that end only being
drawn out from contact to permit of the lever acting as described.
I prefer to fit my outside guide irons to the step plates as shown, or to
fit the step plates to the irons, and to carry my inside guide irons round

page_text: from one horn plate to the other across the engine to which as one piece
it would form a stay or brace.
And having now described the nature of my said Invention and in
what manner the same is to be performed, I declare that I claim,-
The improved safety apparatus by which sound signals can be opened 5
on railway engines as and for the purposes set forth.
Secondly. I claim the combination of appliances forming an
apparatus by or through the severing or withdrawal of a wire can be
caused to operate a sound signal, substantially as set forth and shown.
Thirdly. I claim the severing or cutting of a wire by a moveable blade 1
in the manner and for the purposes set forth.
In witness whereof I, the said William Thomas Cassel Pratt,
have hereunto set my hand and seal, this 26th day of May,
One thousand eight hundred and seventy-four.