IMPROVEMENTS IN APPLYING ELECTRICITY
Year: 1855

page_text: LETTERS PATENT to Thomas Allan, of Adelphi Terrace, in the City of
Westminster, Civil Engineer, for the Invention of IMPROVEMENTS IN
APPLYING ELECTRICITY."
Sealed the 16th May 1856, and dated the 27th November 1855.
PROVISIONAL SPECIFICATION left by the said Thomas Allan at the
Office of the Commissioners of Patents, with his Petition, on the 27th
November 1855.
I, THOMAS ALLAN, of Adelphi Terrace, in the City of Westminster, Civil
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN APPLYING ELECTRICITY" to be as follows:-
To effect an electrical communication between different parts of a train and
the engine driver, I employ an electro-magnetic apparatus adapted for a short
circuit, with a constant battery (as patented by me, February 8th, 1853,) placed
on the engine at the side of it, with one line of communication through the train
to the guard's van, the circuit being completed by the earth. The electro-magnetic
apparatus will act on a bell and indicator at the same time if required, and so
give the necessary signals to the eye and ear simultaneously. This apparatus
will have to be put into action by another or relay. instrument, which may be
formed of a multipoled magnet, as described in the Specification of my former
Patent, dated Twenty-fourth of June 1852, suitable for a long circuit, and

page_text: capable of being worked with certainty from the guard's van, or any other part
of the train, if thought desirable. I further apply or adapt this principle of a
relay in another mode, when by means of a reversing apparatus in the guard's
van I work a needle apparatus, and so signalize to the engine driver the three
common railway signals, white, green, and red, while at the same time it will
work the relay, which will keep the bell ringing, and so draw attention to the
signals. These plans and arrangements may likewise be applied to signalizing
trains from station to station; and all the general signal work of a railway.
The line of communication may be effected in various ways; but if by one line
run out along the foot boards or otherwise, in order to provide against
breakage and disruption, I employ a strand wire of mixed metals formed and
insulated, as described in the Specification of my Patent of 12th August
1853
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Allan in the Great Scal Patent Office on the
27th May 1856.
TO ALL TO WHOM THESE PRESENTS .SHALL COME, I, THOMAS
ALLAN, of Adelphi Terrace, in the City of Westminster, Civil Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of November, in the year of our
Lord One thousand eight hundred and fifty-five, in the nineteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Thomas Allan, Her special licence that I, the said Thomas Allan,
my executors, administrators, and assigns, or such others as I, the said Thomas
Allan, 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
APPLYING ELECTRICITY," upon the condition (amongst others) that I, the
said Thomas Allan, my executors or administrators, by an instrument in
writing under our, or their, or one of their hands and seals, should par-
ticularly 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.

page_text: NOW KNOW YE, that I, the said Thomas Allan, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
My Invention consists in the application of electricity by the employment
of a relay and two separate circuits to produce signals to the eye and car
simultaneously.
One particular application of my Invention is communicating between
guard and engine driver upon a railway train, and the manner in which I
proceed is as follows:-For the purpose of communicating between guard and
driver, I place on the engine a relay, local battery, gong or bell, and indicator,
with one line of communication through the train to the guard's van (the
circuit being completed by the earth). In the guard's van I place a contact
maker to put the relay on the engine into action. The relay (by means of the
local circuit or battery) will set in action the bell and indicator, and so draw
attention, and give the required signals to the eye and ear simultaneously.
The relay most suitable for such purposes is one formed of a many-poled
magnet. I further adapt a relay in another manner, when, by means of a
reversing apparatus in the guard's van, I work a needle apparatus placed on
the engine, and so signalize to the engine driver the three common railway
signals, white, green, and red, or other analogous signals, at the same time the
relay on the same circuit will, by means of the local circuit or battery, set the
bell into action, and so draw attention to the signals. I prefer. this latter
system, as it is next to impossible to make any wrong signal, which might
occur with the former arrangement if the relay were to act of its own accord,
by any excessive jolting of the engine or otherwise.
The foregoing plans and arrangements may likewise be applied to signalling
trains from station to station, and all the general signal work of a railway, and
also for signalling purposes in general where it is desirable to draw attention
to the eye and the ear simultaneously. The line of communication may be
effected in various ways; but if by one line run out along the foot boards or
otherwise, in order to provide against breakage and disruption, I employ a
conductor made of a strand of wires of mixed metals, formed and insulated
as described in the Specification of Letters Patent granted to me the Twelfth
day of August, One thousand eight hundred and fifty-three.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that I. claim,-
First, the employment of a relay and two separate circuits for producing

page_text: the necessary signals to the eye and ear simultaneously through any length of
train, whether stationary or in motion, in the manner herein-before described.
Second, I claim the employment of two circuits and of a relay and index
needle acted on by a reversing instrument or pole changer in the guard's
van or other part of a train, for the purposes and in the manner herein-before
described.
And, third, I claim either of the arrangements and combinations before
described for all signalling purposes in general.
In witness whereof, I, the said Thomas Allan, have hereunto set my
hand and seal, this Twenty-seventh day of May, One thousand eight
hundred and fifty-six.
THOMAS ALLAN. (L.S.)