IMPROVEMENTS IN ELECTRIC TELEGRAPH APPARATUS POR TRAIN SIGNALLING AND Working the TRAFFIC ON RAILWAYS UPON THE BLOCK OR SPACE SYSTEM; PARTS OF WHICH APPARATUS ARE APPLICABLE TO AND FOR OTHER PURPOSES
Year: 1875

page_text: LETTERS PATENT to Richard Robert Harper, of No. 19, Salisbury
Street, Adelphi, W.C., Electric Telegraph Engineer, for the Inven-
tion of "IMPROVEMENTS IN ELECTRIC TELEGRAPH APPARATUS POR TRAIN
SIGNALLING AND Working the TRAFFIC ON RAILWAYS UPON THE BLOCK OR
SPACE SYSTEM; PARTS OF WHICH APPARATUS ARE APPLICABLE TO AND FOR
OTHER PURPOSES."
Scaled the 1st June 1875, and dated the 28th January 1875.
PROVISIONAL SPECIFICATION left by the said Richard Robert Harper
at the Office of the Commissioners of Patents, with his Petition,
on the 28th January 1875.
I, RICHARD ROBERT HARPER, of No. 19, Salisbury Street, Adelphi,
W.C., Electric Telegraph Engineer, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN ELECTRIC TELEGRAPH Apparatus for
TRAIN SIGNALLING AND WORKING THE TRAFFIC ON RAILWAYS UPON THE BLOCK OR
SPACE SYSTEM, PARTS OF WHICH APPARATUS ARE APPLICABLE TO. AND FOR OTHER
PURPOSES," to bo as follows:-
'
The first part of my Invention relates to that part or portion of the
signalling instrument intended to be used or employed for working.the
A

page_text: "block
"
"
or space" system of sigualling, and it consists in a con-
trivance fitted or applied to the front of the instrument case, in
connection with the exterior portions of the plunger or tapper by which
only one of any two (or more) such plungers or tappers can be worked
or actuated at the same time, and whereby or by the use or employ-
ment of my Invention no accidental or other confliction of signalling
can take place. This I effect by making a sliding guard plate and
screen piece for sliding over and covering up one of the engraved faces
or indicating dials alternately, which are employed to shew the last
signal sent, and thus before such guard plate or sliding screen leaves the
one plunger or tapper free to be moved, it has secured the other upon
which it is made to slide, and so to retain it or hold it fast and prevent
the operator acting upon it. Instead of sliding horizontally such guard
or screen plate, it may be mounted as a vibrating or suspended rocking
arm, or double fork piece, the slots or grooves therein alternately taking
on to (or over) the one or the other of the external projecting portions of
the plunger or tapper, or on to, upon, or over a collar or other fixed
.projection thereon provided.
$$
"
The second part of my Invention relates to improvements in the dial
portion of such (or other) signalling instruments, whether employed for
the purpose of actuating a pointer or pointers, or the miniature
semaphore arms (as used in block or space signalling on railways),
and it relates to a certain novel form, arrangement, and disposition of a
soft iron curved and combined double needle (or armature of the form
described), which is magnetised by induction having two poles of the
same name" employed with (or in conjunction with) a needle of the
opposite polarity, the armature being of a circular form is composed of
two portions of iron or steel combined together. I use or employ such
last mentioned portion of the apparatus (as fitted in such Instrument.
cases) by mounting a permanent magnet centrally with its poles
vertically one above the other, and on cach side thereof I mount one
pole of an electro-magnet, the needle described being hung freely in
front of the poles of the permanent magnet, and beneath the terminals
of the electro-magnet or the face of the electro-magnet poles which are
slightly in advance of or above (or before) the poles of the permanent
magnet. The axle of the armature or needle has fitted upon the
exterior and visible portion thereof, outside the dial, the miniature
semaphore arm, or the index or pointer (as before-mentioned), which is
.

page_text: mounted thercon.
The current ou traversing the electro-magnet
magnetises the compound armature attached thereto; one pole thereof
attracts the curved moveable armature, the other pole in like manner
repels the other end of the same armature, whilst the pole of the electro-
magnet which is repelling the said armature is at the same time
attracting the inner needle (which is mounted upon the same axle),
and the reverse pole of the electro-magnet at the same time repels it.
.
The third portion of my Invention relates to a novel arrangement of
"key," whereby the instrument is kept entirely free from the disturbing
effects of lightning, earth currents, line contacts, and such like disturbing
causes, and this I effect by à novel apparatus, which is as follows:-
When a call signal is received from the distant end (upon a bell or gong
in connexion with such apparatus) I cause the insulated end of the
plunger or tapper to come in contact with and press backward a spring.
connected with the line and bell, which causes it to leave contact with,
the connexion against which the first-mentioned spring (when in its
normal position) rests, and so make contact with a spring contact piece.
(or pieces) behind it, which is (or arc) in connexion with the clectro-
magnet of the receiving index and earth. In order to render this part.
of the apparatus complete and effective, I provide and mount four.
springs, two on each side of the line and bell spring, but each pair is
mounted upon separate blocks, and each pair of springs has (at their:
respective vibrating ends) an insulated plate to which they are attached,
the objects of which arrangement is as follows:-In all other arrange-.
ments of apparatus the receiver of a signal has heretofore been liable to
receive the incoming signal on the sending portion of his instrument.
Now to prevent this and the consequent derangement to which it would
be liable, I also arrange, dispose, and employ two springs in or in con-
nection with a bell or relay, which upon an incoming current attracting.
the armature of the said bell (or relay), the springs are both caused to
be brought into metallic contact, so that one of such springs is attached
to the incoming wire of the said bell or relay, the other is connected to
one of the couples of the 4 springs from whence it passes direct to the
line wire block of the sending apparatus. The armature of the bell (or
relay) when at rest in its normal position rests against a stop, which stop.
is in connexion with one of the springs of the other couple in the.
receiving instrument, and which in turn is connected to the electro-
magnet of the sending coils of apparatus. It will thus be understood
0
1
L

page_text: :
that upon the plunger or key of the receiving portion of the instrument
being pressed in, the earth wire of the sending portion is severed, and
also the line circuit of the other couple, one of which is in direct contact
with the line wire and receiving coil; and this arrangement is to
prevent any error being made if the receiver uses both the sending and
receiving portions of the apparatus at the same time, or if they are
operated upon at the same time.
The fourth part of my Invention relates to a system of "interlocking "
or preventing the signals or directions for working the traffic between
branch lines and the main line (and vice versa); and this arrangement
is also applicable to single lines of railway to prevent two trains being
taken or admitted on to one section of the line at the same time. It
consists in so mounting (within the instrument case as to be alternately
acted upon by one or the other of the plungers, keys, or tappers), à
double ended lever arm or "yoke" which shall alternately disconnect
or connect (by means of a spring), the battery or carth connections as
between two or more instruments or sets of apparatus, so that the signals
and working directions shall be consonant, consistent, and harmonious,
and in no case be conflicting or contradictory; and this I prefer to
apply or mount upon the interior bottom of the case, and the position
of such "yoke" is changed from one side to the other by such move-
ment, and the "tail piece" of the "yoke" is either brought into or
removed from contact with the metallic spring.
The fifth part or portion of my Invention relates to an improved
battery (employed for working such apparatus or instruments), or a
modification of the form and arrangement of the cells of batteries of
that kind or description known as the "Smee" battery, in which a plate.
of silver is used or employed in combination with zinc plates and
mercury: It consists, first, in making and forming the silver plates
with vertical corrugations, to give them structural stability to resist the
tendency vertically, to buckle, bend, or bulge out and come in contact
with the zine; and secondly, in so forming the cells with a small pocket
on the inner surface at the bottom of the inside for receiving a limited
quantity of mercury, into which the ends of the zinc plates dip, and are
maintained in a "malgamated". (or an amalgamated) condition. Thus,
instead, of. a large quantity of mercury being diffused over the entire
bottom of the cell or in and over an annular space or portion thereof, I
limit the mercury holding portion and requirements by my improvement

page_text: to a small cell on each side only, slightly in excess of the width and
thickness of each zinc plate or thereabouts, and of a height or depth, say
of inch or more, and such pockets may form the feet upon which the
jar or cell may stand,
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Richard Robert Harper in the Great Seal Patent
Office on the 28th July 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
ROBERT HARPER, of No. 19, Salisbury Street, Adelphi, W.C., Electric
Telegraph Engineeer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of January, in the year of
our Lord One thousand eight hundred and seventy-five, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Richard Robert Harper, Her special
licence that I, the said Richard Robert Harper, my executors, admini-
strators, and assigns, or such others as I, the said. Richard Robert
Harper, my executors, administrators, and assigns, should at any time.
agree with, and no others; from time to time and at all times there-
after 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 Inven-
tion for "IMPROVEMENTS IN ELECTRIC TELEGRAPH APPARATUS FOR TRAIN
SIGNALLING AND WORKING THE TRAFFIC ON RAILWAYS UPON THE BLOCK OR SPACE
SYSTEM, PARTS OF WHICH APPARATUS ARE APPLICABLE TO AND FOR OTHER
PURPOSES," upon the condition. (amongst others) that I, the said Richard
Robert Harper, 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 Richard Robert Harper, do hereby
declare the nature of my said Invention, and in what manner the

page_text: same is to be performed, to be particularly described and ascertained in
and by the following statement and accompanying three Sheets of
Drawings.
"
The first part of my Invention relates to that part or portion of the
signalling instruments intended to be used or employed for working the
"block
«
or space" system of signalling, and it consists in a contrivance
fitted or applied to the front of the instrument case, the moving screen
piece or guard plate of which may be fitted either before or behind the
door, or the moveable lever piece (in a single plunger instrument) may
be fitted behind the door or the opening front of the instrument case,
and such interior fittings are in connection with the exterior portions
of the plunger or tapper, by which only one of any two (or more) such
plungers or tappers (when there are two or more) can be worked or
actuated at the same time, and whereby or by the use or employment of
my Invention no accidental or other confliction of signalling can take
place. This I effect by making a sliding guard plate or screen piece for
sliding (either externally or internally) on the door or cover of the
instrument, and so thereby covering up or exposing one of the engraved.
faces or indicating dials (alternately); the exposed dial or face is
employed to show the last signal sent, and by this meas also before such
guard plate or sliding screen leaves the one plunger or tapper free to be
moved it has secured the other upon or over which it is made to slide
and so to retain it or hold it fast and prevent the operator acting upon it.
Instead of sliding horizontally such guard or screen plate it may be
mounted as a vibrating or suspended rocking arm or double fork piece,
the slots or grooves therein alternately taking on to (or over) the one or
the other of the external or internal projecting portions of the plunger
or tapper, or on to, upon, or over a collar or other fixed projection thereon
provided.
Where two plungers are employed on the front of the instrument case
the screen plate may be mounted inside and be operated from the
outside by means of a knob or handle, by which it may be made to
vibrate from right to left and vice versa, and the Jocking screen piece
has engraved upon it or mounted upon the face thereof, one, two, or
more signals or directions, one only of which at a time can be seen
through a central opening provided for that purpose (and which opening
may be glazed in the ordinary manner), so that where it is engraved
with two signals only; on its being moved to the right it will lock the left-
・

page_text: hand plunger and leave the outer free, or vice versû, and when it-is
vertical or in a neutral position it will lock both plungers, and will then
show the neutral signal or other indication upon the dial (where 3 dials
are used), and where two signals only are engraved the signal last sent.
will be exhibited centrally. In this arrangement only the two plungers;
and the knob or handle of the locking plate project externally, whilst;
the locking plate itself is fitted behind the door or within the case..
And instead of the vibrating or suspending rocking arm or double ended
lever taking on to or over a fixed projection near the knob or by the
slots, groove, or collars, the rocking arm may be made to slide in front of,
intervene and interpose alternately between the points of pistons or
plungers and the "line spring" or springs. This arrangement being
applied beyond the point of the plunger or piston, will cause one or
other of the plungers or pistons to be blocked or stopped, whilst the other:
is free, and vice versa.
In some cases, as where I employ a single plunger only in connection
with a pointer which is made to point to the last signal sent on the
engraved face of a dial plate, and also for the purpose of sending
alternate currents and signals as hereafter described, I mount tho
plunger in any convenient position on the case; the plunger has a lever
or tail piece attached thereto and fitted thereon, which alternately*
passes or vibrates from one side to the other for the purpose of acting
upon the "line spring" or springs in connection therewith; and in
order to prevent the position of the tail picce from being changed
inadvertently, and thereby altering the signal upon the depressing of'
the plunger, I use an improved form of plunger which must have
communicated to it in addition to its partial rotation, an inward and an
outward, or a backward and a forward movement in connection with a
recessed or notched cock or bracket which acts as a lock to the plunger,
so that to change the position of the plunger it must, firstly, be pulled
forward to unlock it; secondly, turned from right to left or vice versà;
thirdly, after turning the required distance so that the projection
coincides with the slot of or in the cock or bracket (or other suitable
form of lock), the plunger is then depressed to make the required.
signal, when the index of the dial will coincide with the position of the
pointer..
-
}
)

page_text: " name
"
for the purpose of working a pointer or pointers or miniature "semaphore
arms"(as used in block or space signalling on railways), and it relates
to a certain novel form, arrangement, and disposition of a soft iron
curved and combined double needle (or armature) of the form described
and as illustrated on Figure 2, Sheet 1, applied to an index or pointer,
and also by Figure 12, in Sheet 3 (as modified to adapt it to the working
of a miniature semaphore arm and double needle or armature), which is
magnetised by induction, having two poles of the same
employed with (or in conjunction with) a needle of the opposite polarity.
The armature or needle being of a circular form is composed of two
portions of iron or steel combined together. I use or employ such last-
mentioned portion of the apparatus, as fitted in such instrument cases,
by mounting a permanent magnet centrally with its poles vertically one.
above the other, and on each side thereof I mount one pole of an electro-
magnet, the needle or armature described being hung freely in front of
the poles of the permanent magnet, and beneath the terminals or arma-
tures of the electro-magnet or the face of the electro-magnetic poles, which
are slightly in advance of or above or before the poles of the permanent
magnet. The axle of the armature or needle has fitted upon the exterior
and visible portion thereof, outside the dial, the miniature semaphore
arm or the index or pointer (as before mentioned), which is fitted or
mounted thereon. The current or traversing the electro-magnet mag-
netises the armature or poles attached thereto; one pole thereof attracts
the curved moveable armature, the other pole in like menner repels the
other end of the same armature, whilst the pole of the electro-magnet,
which is repelling the said armature, is at the same time attracting the
inner needle (which is mounted upon the same axle), and the reverse
pole of the electro-magnet at the same time repels it.
3.
To illustrate this part of my Invention, as applied to a distant signal
repeater, in order to make the same more effective and complete, and in
order to show the actual position or exact state of the distant semaphore
arm (or other form of signal), I mount and apply (in addition to those
employed for the purpose as before described) a second pair of coils
inside the case, in or upon which is the miniature semaphore arm
(or other signal in miniature); which is shown in such a position
that immediately the semaphore of the distant signal (for example)
drops or falls in the slightest degree from the angle of 90° contact .is
made, and the current traverses through these coils (as well as through
:

page_text: the coils before mentioned), and an armature having a lever attached
thereto working on a detent depresses a tail piece or counterpoise
attached to the axle connected to the miniature semaphore arm on the
dial, and thereby depresses the miniature semaphore arm on the dial
from a right angle to, say 45° or less, which indicates at once that the
distant semaphore has fallen, whatever may be the minuteness of the
amount of such motion. When using this arrangement of distant signal
repeater I prefer to employ, in combination therewith, a "commutator"
(as herein-after described) for sending alternate currents, and which I
prefer to apply and attach to the lever or rod of the distant signal
within the operator's cabin.
The following is a further explanation of the instrument herein lasť
mentioned, and of the mode of working it :-I employ in connection
with the repeater a commutator of an improved form and arrangement
for reversing the battery poles; and this commutator, as, before stated, I
prefer to fix to the lever or rod that works the distant semaphore (or
other distant signal) from the signalman's cabin. In addition to the
two springs usually employed from the battery in connection with such
like commutators I employ four springs, that is, two on each side, one of
each being connected to a local battery or portion of the line battery,
and the other two are connected direct to the second pair of coils
attached to the miniature repeater.
The action and working of such commutator is as follows:-Upon
the operator pulling over or otherwiśc altering the position of the lever
in the signal cabin the distant arm begins to fall, and electric com-
munication is thus established at the distant signal arm (or other
signal), and the miniature signal falls likewise, although the current is
then in the same direction as it was when it raised the miniature arm,
inasmuch as the tail piece attached to the armature of the second pair
of coils. has a preponderance of power over the magnetic force of the
electro-magnet that actuates the soft iron needles or armatures. On
pulling over or altering the distant signal to its central or half-way
position the ordinary forms of commutator would fail by reason of the
battery poles in such commutators having to be insulated from cach
other, as the spring from the battery in such case would be resting on
the insulation between the poles, and therefore no current could pass to
the line circuit. Now in my improved form of commutator when the
lever. of the signal arm is brought to the half-way position a current is

page_text: '
made to pass locally through the extra coils by employing the extra
springs before mentioned, and thereby the "half-way position" of the
distant signal is correctly shown on the miniature arm or signal.
Although I prefer to use two extra coils for actuating an armature in
connection with such before-mentioned repeater yet in some cases it
may be found more convenient, and I intend hereby to claim the use or
employment for this purpose of one pair of coils, but when one pair
only is applied they are wound with two circuits and connected in the
usual way, so that the two circuits work together when contact is made
with the line circuit, and one circuit only when contact is made to show
the half-way signal. Thus by the use of the apparatus and the arrange-
ment just described I am enabled to show on the instrument the actual
position of the distant signal without a continuous waste of battery
power on either side, as the battery power is only used during the
passage of the distant signal through its arc. At the same time it
becomes impossible for the operator or any other person to reverse the
miniature signal without first pulling over the distant signal lever in
the signal box, and thereby changing the poles of the commutator, as
the magnetic induction is cach time reversed in the armatures attached
to the electro-magnet of the line circuit. This part or portion of my
Invention also provides a check and means of indicating the state of
tension or elongation of the distant signal wire and the resulting action
upon the signal itself, and it thus meets a requirement hitherto
unprovided for as affecting a relation and accord between the mechanical
movement and action of the signal lever upon the signal wire, and the
signal itself, and the electric or electro-magnetic indicating apparatus or
instruments in the signal box.
66
The third portion of my Invention relates to a novel arrangement of
"key" whereby the receiving portion of electro-magnetic instruments
is kept entirely free from the disturbing effects of lightning, earth
currents, line contacts, and such like disturbing causes. And this I
effect by a novel apparatus and mode of working, substantially as
follows: When a "call" signal is received from the distant end upon
a bell or gong in connection with such apparatus the operator in
response to such call signal presses a plunger or tapper in connection
therewith which causes the insulated end of such plunger or tapper to
come in contact with and press backwards a spring (which I call the
line spring) having an insulated cross bar attached thereto. The cross

page_text: "
bar having two insulator plates, one on each side of its upper surface,
and the line spring having a small and. weaker spring attached to its
vibrating end, which is interposed between the said line spring and the
stop against which the line spring rests when in its normal position, the
stop being in connection with the bell or relay, and thence to earth.
On pressing the plunger or tapper in responding to the "call" signal
the insulated end of the plunger or tapper presses the line-wire spring
away from the stop and the small spring attached thereto being weaker
remains in contact with the stop, the line-wire spring is thus brought
into metallic contact with the spring or springs placed beneath, and
which in turn conduct the incoming current to. the receiving index of
the apparatus while the weaker spring attached to the line spring
conducts a portion of the incoming current through the bell or relay to
carth. As the coils of the bell or relay are wound with a wire of greater
resistance than the receiving index the bell or relay acts as a "shunt
until the plunger or tapper is still further depressed, when the weaker
spring leaves the stop and the whole of the incoming current passes
through the receiving index and thence to earth. It will thus be under-
stood that the line wire makes contact with the receiving spring or
springs of the index before contact is broken with the line wire stop.
On each side of the line spring I mount two springs on separate blocks.
with their vibrating ends resting on the upper side of the before-
mentioned insulated cross bar, and the block of a spring of one couple is
connected to the coils of the sending index of the apparatus, and the
other spring of the said couple is likewise connected to the-stop against
which the armature of the bell or relay rests when in its normal position,
the stop being insulated from the other portion of the bell or relay, and'
the armature being connected through the plate to earth. In like'
manner one of the blocks of the other couple is in connection with the
line wire block of the sending portion of the apparatus, and the other to
a spring mounted on the plate of the bell or relay, and which upon the
armature being attracted is connected to the incoming wire of the bell'
or relay by an insulated plate attached to the armature. Thus when the
armature of the bell or relay is attracted the earth wire of the sending
portion is disconnected and the incoming current is made to pass in two
directions to the bell or relay, so that the operator depressing the key of
the sending portion does not "break down" the incoming current, and
therefore has no effect on the sending portion of the apparatus, and as
the two or more couples of springs are disconnected when the plunger
t

page_text: of the receiving key is depressed it becomes impossible for the receiver
of a signal to make a contradictory signal or signals should he attempt
to use both the sending and receiving keys or portions of the apparatus
at the same time, or if the "sending" portion is operated upon for
"receiving."
In all other arrangements of apparatus heretofore used the receiver of
a signal has been able to receive the incoming signal on the sending
portions of his apparatus; now, to prevent this and the consequent
derangement to which it would be liable I have provided the novel
arrangement of apparatus last herein described.
On busy circuits or where considerable traffic has to be regulated or
controlled, should the operator not receive an immediato reply to his
"call" signal in giving "a train on " to the distant end, I arrange for a
slide or cover to be brought over the necessary key, or the plunger or
tapper, and by so doing forces in or makes the circuit of the plunger,
key, or tapper of the receiving portions of the apparatus, and thereby
leave the operator free to perform his other functions or duties till such
signal is responded to, when he must in the first place restore the slide to
its "proper" position before he can acknowledge the correctness of the
signal sent to him.
The fourth part of my Invention relates to a system of "interlocking"
or preventing a confliction of or between the signals or the directions for
working the traffic between branch lines and the main line and vice
versâ, and this arrangement is also applicable to single lines of railway
or on sidings to prevent two trains being taken upon or admitted on to
one section of the line at the same time. It consists in so mounting
(within the instrument case) as to be alternately acted upon by one or
the other of the plungers, keys, or tappers a double-ended lever arm or
"yoke," which shall alternately disconnect or connect (by means of a
spring or springs) the battery or earth connections, as between two or more.
instruments or sets of apparatus, so that the signals and working direc-
tions shall be consonsonant, consistent, and harmonious, and in no case be
conflicting or contradictory, and this lever arm or yoke I prefer to apply
or mount upon the interior bottom of the case, and the position of such
"yoke" is changed from one side to the other by such movement, and
the "
tail-piece" of the "yoke” or double-ended lever arm is either
brought into or removed from contact with the metallic spring.. In

page_text: relation to this portion of my Invention in some cases the absolute block
system is used, and what is turned a "permission signal" is (or may be).
given on the block instrument to the signalman at the first station
removed from a junction, and the line is "given as cleared during the
passage of a train between the first and second stations removed from
the junction. Now in order to render this part of my Invention effective
while the train is between the first and second stations from the junction.
I use or employ the above-mentioned lever, yoke piece, or other suitable
contrivance fitted in the instrument case for the purpose of disconnecting
the other instruments in the junction box. And I use a lever and a disc
of ebonite or other non-conducting material fitted with metallic studs or
plates combined with a spring or springs attached to and worked by the
lever rod or arm of the junction semaphore during the passage of a train
between the junction and the first station or signal cabin from the
junction; thus the other instruments are disconnected during the passage
of a train travelling over the two sections of line from the junction, firstly,
by the instrument, and secondly, by the lever rod or semaphore arm.
In using a single plunger or rocking lever instrument for interlocking
junctions, sidings, or single lines of railways, I prefer in some cases to
apply a circular plate or disc of ebonite or other non-conducting material
fitted with metallic studs or plates combined and applied within the
instrument case for the purpose of alternately connecting or discon-
necting the spring or springs in connection therewith so as to connect
or disconnect thereby one or more instruments, and thus prevent con-
Hiction in signalling, as herein-before described.
The fifth part or portion of my Invention relates to an improved
battery (intended to be employed for working such or like apparatus or
instruments and for other purposes), and is a modification of the form
and arrangement of the cells of batteries of that kind or description
known as the "Smee" battery, in which a plate of silver is used or
employed in combination with zinc plates and mercury.
My improvements in batterics consist, first, in making and forming
the silver plates with vertical corrugations to give them structural
stability, to resist the tendency (vertically) to buckle, bend, or bulge
out and come in contact with the zine; and secondly, in so forming the
cells with a small pocket or pockets on the inner surface at the bottom*
on the inside for. receiving a limited quantity of mercury, into which

page_text: <<
the ends of the zinc plates dip and are maintained in a malgamated"
(or an amalgamated) condition. Thus, instead of a large quantity of
mercury being diffused over the entire bottom of the cell, or in and over
an annular space or portion thereof, I limit the mercury-holding portion
and requirements by my improvements to a small cell on each side only
of a size slightly in excess of the width and thickness of cach zinc plate
or thereabouts, and of a height or depth, say, of half an inch or more;
and such pockets may form the feet upon which the jar or cell may
stand.
In the accompanying three Sheets of illustrative Drawings I have
shown some of the modes and methods in which I prefer to apply the
several parts of my Invention.
In Sheet 1 Figure 1 is an external, front view of the instrument case
and its several exterior parts, and it shows the index or pointers resting
against the stops upon the dial, indicating the last signal sent on each
portion; and it also shows the horizontally moving arrangement of a
sliding guard plate or screen piece with the slots therein for alternately
locking one or other of the plungers, keys, or tappers; and in the
position thus shown it has covered up the "line clear" engraved face,
and likewise locked the plunger corresponding to such engraved face,
leaving the other key (say "train on line "free) to be acted upon.
-
Figure 2 is a vertical sectional view, or a view of the interior portion
of an instrument case, as in Figure 1, and it shows at the lower portion
thereof the door of the instrument case thrown back upon its hinges,
exposing the cock or bracket which guides the pistons or plungers for
actuating the commutator or commutators; whilst the upper portion of
such view exhibits, by the dotted lines, the soft iron curved needle or
armature, and the disposition of the electro-magnets and their armatures
respectively.
Figure 3 is a plan view of the sliding guard plate and screen as
applied in Figures 1 and 2.
Figure 4 is a plan view of the door or front of the instrument case
fitted with two plungers or keys, and a sliding guard plate and screen
piece on the external face thereof; the double-ended lever arm or
"yoke" piece is mounted by means of a central pivot upon a plate, and
it is acted upon alternately by means of a stud on a tail-piece attached
to cach plunger, key, or tapper, and so is moved on or off the contact.

page_text: .
plate. In this Figure the right-hand plunger or key is held by the
guard plate, and the contact spring is shown as resting upon the contact
plate; and when the guard plate is drawn across over the left-hand
plunger it secures it; and by pressing the right-hand plunger the
contact spring is made to leave the contact plate, thereby disconnecting
the earth or battery of the corresponding instrument.
⚫ In Sheet 2, Figure 5, shows a portion, of the front of an instrument
with a single plunger and pointer combined, of which Figure 6 is a side
view of the front portion, which carries the whole of the mechanism in
connection therewith. In this case the plunger or tapper has the
compound motion and action herein-before referred to in connection
with this portion of my Invention, and this will be readily understood,
as will also the mode in which it operates upon the pointer, by reference
to those Figures, whilst the angular notch or recess in the cock is shown
by dotted lines on the front of the case, Figure 5.
Figure 7 is a front elevation of the lower part of the instrument case,
in which the two plungers are mounted onc above the other, as
used in semaphore block or space telegraph instruments, and it exhibits
a modification of the sliding guard or screen plate, which is there shown
as being moved vertically in its arc, the notches or slots therein taking
on to or engaging with one or other of the plungers or keys.
Figure 8 exhibits a similar portion of an instrument case, in which the
two plungers or keys are mounted horizontally, and the screen plate is
mounted and fitted behind or at the back of the door (or front) of the
casc. The lower central opening is a glazed opening or "sight piece."
By the knob or handle projecting externally the position of the guard or
screen piece is moved from one position to the other, and unlocks
alternately one plunger or key.
Figure 9 shows the details of my improved "receiving key" apparatus
as herein described without its cover, and it may be fitted or worked
vertically or horizontally. The line spring which is secured to a metal
block at one end has at its lower end a weaker spring (1a) which remains
in contact with the line spring stop (6) which permits of the motion of
the spring (1) behind it. On the right side are shown two separate and
independent springs (2, 2*,) mounted upon separate blocks, with their
lower or free ends-resting upon the insulated plate (4) and so connecting
the two together when in their normal position. On the left side are

page_text: L
two similar springs (3, 3ª,) similarly mounted and in like manner acting
upon the insulated plate (4). A spring (5) is mounted behind the spring
(1) but upon a flat plate, the free end of which spring (5) makes
· contact with (1) when it (1) is pressed by the key, plunger, or tapper.
The pressure of the (single) plunger is received upon spring (1) at a
point below the insulated cross bar and above the spring (1ª).
.
Figure 10 exhibits a view of a pair of coils and apparatus for a relay
or bell to be worked in connection with the receiving key, Figure 9 (and
also Figure 2, Sheet 1), in the manner herein-before described, the one
contact spring being connected to the incoming wire of the coils, and the
other being connected to 2ª (on Figure 9), while (2, Figure 9) is in
connection with 2, Figure 2 (Sheet 1). The insulated cock (x) has its
connection with (3) Figure 9, and 3ª, Figure 9, being connected with Y,
Figure 2 (Sheet 1), whilst 1, Figure 9, is connected to Z, Figure 2
(Sheet 1), and thus the connection between the receiving and sending
portions is shown. The block making contact with the incoming coil
wire of Figure 10 is connected to (6) Figure 9.
In Sheet 3 Figure 11 is a front elevation of a miniature semaphore
repeater connected with the distant signal, the semaphore arm being
shown by the firm lines in its half-way position, showing that the distant
signal arm has dropped. The action of this instrument has already been
explained.
Figure 12 is a view similar to Figure 11, but the right-hand portion of
the front is removed to exhibit the electro-magnetic arrangement; the
'position of the combined needle and armature is there shown dotted in
centrally, and the armature of the small coils is there shown as being
attracted, the tail picce bringing the combined needle or armature into a
central position, which leaves the semaphore arm in its half-way
position..
Figure 13 is a detached view of the magnetic arrangement and of the
'curved needle or armature with the magnetic poles of the permanent
magnet placed behind it, as herein-before explained.
Figure 14 is a plan view of my improved commutator, a description of
which and its action having been given, it is unnecessary to further
explain it here, except that the commutator is shown with the battery
springs resting on the insulation, the two springs C. and Z being connected

page_text: to the local battery, the other two springs (L, C,) being connected to the
local or small coils shown in Figure 12.
Figures 15 and 16 are views of my improved battery in which the
corrugated plate is shown, whilst the zinc plates Z, Z, are shown with
their lower ends in the pockets containing the mercury and the wires
dipping into the same, as herein-before described.
Instead of sliding horizontally the sliding guard or screen picce may
be made to slide vertically over the plungers, knobs, keys, or tappers, or
it may be made to take into, over, or under a fixed stud, collar, or other
projection or groove provided on or in the piston or lever of the plungers,
keys, or tappers.
j
The slide, sliding guard plate, or screen piece, as also the yoke piece,
for disconnecting the circuit may be used or employed whenever and
wherever a continuous vibratory action is desired to be produced,
whether for electric telegraphic purposes or as, a brake or circuit closer
or as a "switch" also where continuous currents are employed, are
employed such as, for instance, where a two or three wire system is used
in block signalling.
The soft iron or steel needles or curved armatures may be employed. in
speaking instruments and in polarized relays.
My batteries as described may be used for various other purposes than
for working the instruments, as herein set forth.
Having now described my Invention of improvements in electric
telegraph apparatus for train signalling and working the traffic on
railways upon the block or space system, parts of which apparatus aro
applicable to and for other purposes, I wish it to be understood that I
am perfectly familiar with all that has been done and published up to
this date by other Patentees of electric signalling apparatus for working
railway traffic upon the block or space system, and also with such
instruments as are in use on the various railways of this country. Also
that I am aware that certain apparatus has been used in certain kinds of
instruments for locking and also for covering, and both for locking and
covering the "signal off" key, and furthermore that a hinged flap has
heretofore been used or employed for alternately covering up one or other
of the engraved dials of certain telegraph instruments, and which flap
is simply turned over by hand and has no locking or interlocking action,
but I also wish it to be understood that those portions of my Invention
B

page_text: which relate to the sliding guard plate or screen pieces as herein
described differ essentially from and perform other functions than those
instruments or apparatus which have heretofore been used or employed
or patented and described, but what I claim is,―
First. The improvements in electric telegraph apparatus for train
signalling and working the traffic on railways upon the block or space
system, as herein limited and defined.
Secondly. The novel contrivances and apparatus and the mode of
applying and working the same for the purposes set forth in the
description of the first part of my Invention, and as herein set forth in
connection therewith.
Thirdly. The novel contrivance of electro-magnetic apparatus
described as in connection with the second part of my Invention, for the
purposes set forth and as illustrated in Figures 2, 12, and 13.
Fourthly. The novel mechanical arrangement and disposition of the 1
magnetic portions of block or space telegraph. instruments, and of
miniature semaphore and other signal indicating dial instruments, as
herein described and set forth.
Fifthly. The improved commutator as described in and in connection
with the second part of my Invention, and as hercin set forth.
Sixthly. The use and employment of the improved commutator, as
herein described and as illustrated by Figure 14 in the accompanying
Sheets of Drawings in connection with semaphore and other distant
signals, and with semaphore and other distant signal repeaters.
Seventhly. The novel arrangement of key instrument and apparatus, 2
as herein described under the third part or portion of my Invention and
the mode of applying and working the same, as set forth herein.
Eighthly. The improved arrangement, and disposition of the bell
and (or) rclay connections, as herein described and as illustrated by
Figure 10.
Ninthly. The novel arrangement and disposition of spring insulators
and contact makers and connections shown in Figure 9, and as herein
described.
Tenthly. The novel arrangement and mode of constructing the
internal mechanism of receiving keys, herein described and set forth.
2
3
3

page_text: Eleventhly. The apparatus and mode or method herein described for
interlocking or disconnecting, having reference to the fourth part or
portion of my Invention, as herein set forth.
Twelfthly. The improvements in batterics herein described and set
forth as forming the fifth part or portion of my Invention.
-
Thirteenthly. The locking of one or more plungers, keys, or tappers,
by the act of unlocking and setting free the one to be operated upon, as
herein described and set forth.
Fourteenthly. The locking or disconnecting of one or more instru-
ments at junctions or sidings by the use and employment of an
insulated disc fitted with metallic studs or plates, substantially as herein
described and set forth.
In witness whereof, I, the said Richard Robert Harper, have
hereunto set my hand and scal, this 27th day of July, in the year
of our Lord 1875.
RICHARD ROBERT HARPER. (L.S.).
Witness,
H. H. M. SMITH,
19, Salisbury Street,
Strand.
W.C.