IMPROVEMENTS IN ELECTRO-TELEGRAPHIC APPARATUS
Year: 1869

page_text: LETTERS PATENT to William Alexander Lyttle, of The Grove, Ham-.
mersmith, in the County of Middlesex, Engineer, for the Invention
of "IMPROVEMENTS IN ELECTRO-TELEGRAPHIC APPARATUS."
Sealed the 29th October 1869, and dated the 11th June 1869.
PROVISIONAL SPECIFICATION left by the said William Alexander
Lyttle at the Office of the Commissioners of Patents, with his
"Petition, on the 11th June 1869.
I, WILLIAM ALEXANDER LYTTLE, of The Grove, Hammersmith, in
the County of Middlesex, Engineer, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN ELECTRO-TELEGRAPHIC APPARATUS," to be
as follows:-
I mount two levers with magnetized steel armatures, so that their
armatures shall be within reach of the magnetic influence of a set of
electro-magnet coils. The armatures are so arranged that a current.
circulating through the coils which will attract one armature to one side.
shall tend to drive the other armature to the other side. Each armature

page_text: is, however, only free to move in one direction, so that a current which
will attract one will not move the other. One of these levers, to be
called number 1 lever, engages at its end furthest from the coils and
axis of motion into the ratchet cut teeth of a metal disc or plate. A
ratchet, spring catch, or detent also engages into the teeth of the same
disc. The disc moves on an axis and is retained when at rest by a spiral
or other spring pressing back a projection on its side or circumference
against a stop pin. When number 1 lever makes, say, four strokes, the
disc is drawn four teeth forward. If the detent catch is now forced back
from the disc, the latter, by the action of the spiral spring flies back
till it strikes against the stop pin from which it started. This function
of liberating the detent by forcing it back is effected by the lever
number 2 of the aforesaid levers when that lever is attracted.
A lever of light construction, to be called number 3 lever, working.
on an axis, and in a plane at right angles to that of the lever number 2,
is first pressed into motion in the following manner, before the No. 2
lever liberates the detent catch. At right angles across the end of
number 2 lever, and in the plane of its motion is fixed a piece of flat
spring, which when the lever moves rubs against a small friction roller
fixed on the axis of number 3 lever, and so makes that lever rise or fall.
There is a hole, slot, or other recess in the face of the ratchet disc into
which when the disc is in proper position the pin or free end of the
number 3 lever can pass. This movement of the number 3 lever I shall
designate "threading," from its bearing some resemblance to the action
of threading a needle. When the hole or opening in the disc is brought
over the point of the number 3 lever at the tenth ratchet tooth or tenth
movement of number 1 lever, "threading i
"is effected by simply
reversing the current, and so bringing number 2 lever into action.
66
°
When threading is effected the number 3 lever has moved through
an angle sufficient to enable it either to liberate a clockwork escapement
or to complete a local battery circuit, so as to ring a trembler or
other alarum bell. Immediately on the cessation of the reversed or
threading" current, the number 3 lever falls back by the action of the
friction spring of number 2 lever. When the disc is advanced, so as to
move the hole in the disc from the threading position, the friction spring
at the end of the number 2 lever merely slips over the friction wheel
on the axis of number 3 lever, pressing that lever first against the face
of the disc, and then, in its further advance, pressing out and so liberating

page_text: the detent or ratchet catch. The disc is then free to fly back to its stop
pin.
I use this arrangement as the means of calling any one telegraph
station without disturbing any of the others as follows:-At one station
of the series in circuit I adjust the ratchet disc of this alarum, so that
the "threading" can be effected after say, the tenth stroke of number 1
lever. The next station instrument is adjusted for "threading" only
to take place at the eleventh stroke of number 1 lever. The third
station instrument will "thread" only at the twelfth stroke of number 1
lever, and so on. It is evident that the imovements of number 1 lever,
which will prepare for "threading" at the first station, will not suffice for
that purpose at any of the others, and that if after sending ten currents
to move the number 1 lever of each instrument in circuit the current is.
reversed" threading," and consequently ringing the alarum, will result
at the first station only.
When an electrical alarum bell is to be set in motion, instead of a.
clockwork alarum, any kind of electrical alarum can be used, but I
prefer one arranged as follows for continuous ringing when once.
started :-
In a line with the vibrating armature of a common electrical trembler
alarum I place a magnetized steel lever moving on an axis, and in the
same plane as the armature. Its arms are of unequal length, the shorter
one resting against the face of the free extremity of the aforesaid
vibrating armature. When, however, the vibrating armature is attracted
by the trembler coils it moves the short arm of the magnetised lever and
so causes, the longer arm of that lever to strike its end or pole against a
piece of iron or magnetized steel (with opposite polarity at the point
of contact). Once the magnetized lever is brought by the vibrating
armature into this position it of course clings in its new position by
the sperior attraction at the end of its longer arm, and at the latter
point it becomes the channel for the current from a local battery, which
will keep the trembler bell ringing till the long arm of the magnetized
lever in question is pushed back, and the circuit is so broken. The
short arm should have opposite polarity to that developed in the nearest
bell coil. The circuit closed by number 3 lever to ring the electric
bell should be a branch of the same battery circuit as that which
is to be closed by the action of the vibrating bell armature and its
magnetised lever with the unequal arms.

page_text: Of course this arrangement of auxiliary magnetized lever to be moved
by the vibrating armature can be applied to any ordinary railway or
other alarums, without the foregoing "threading" mechanism, and in
that case the line current commences the alarum, and the local current
keeps it up through the circuit of the new auxiliary or relay magnet
lever.
The aforesaid lever armatures, designated numbers 1 and 2, which work
the ratchet disc, may also be made to serve for telegraph signalling by-
causing them to actuate the hammers of two: bells or other sounding
media, either by direct impact or by acting as relay levers for laying on a
local current by which to work an acoustic telegraph like that well known
as "Bright's bell telegraph."
A single needle telegraph can also be worked by means of the same
numbers 1 and 2 levers by forming into a hooked curve that end of each
lever which is furthest from the ratchet disc, and by arranging a single
needle pointer so that it shall be tilted over to the right or the left
accordingly as either lever hook is brought into play. The curve of
each hook is in the same plane as that in which the lever moves, and
the concave side of the hook is turned in the direction in which the lever
is free to move. If a vertical needle pointer is arranged so. that it stands
on an axis placed above the plane of motion of the armature levers
numbers 1 and 2, and with two laterally divergent forks or projections
below its axis which shall stand so close to the end of each lever hook as
to almost touch, any movement of a lever hook will of course cause
the needle to tilt over like the cock of a balance. The distance of the
needle pointer axis from the lower extremity of each of the last-
mentioned divergent forks must be such (compared with the distance
between the lever hooks) that when one of the latter moves the needle
fork next the other hook shall describe a circle which will not be touched
or intersected by the stationary fork. The armature hooks and needle
forks may (either or both) be made elastic. If the needle is kept
vertical by a weak spring arrangement, or by the attraction of a
magnet, it will be less likely to oscillate when recovering its
vertical position, and can be regulated to obviate the effect of disturbing
currents.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Alexander Lyttle in the Great Seal Patent
Office on the 9th December 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ALEXANDER LYTTLE, of The Grove, Hammersmith, in the County of
Middlesex, Engineer, send grecting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of June, in the year of our Lord
One thousand eight hundred and sixty-nine, in the thirty-second year
of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said William Alexander Lyttle, Her special licence that I,
the said William Alexander Lyttle, my executors, administrators, and
assigns, or such others as I, the said William Alexander Lyttle, 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 "IM-
PROVEMENTS IN ELECTRO-TELEGRAPHIC APPARATUS." upon the condition (amongst
others) that I, the said William Alexander Lyttle, 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 Scal
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 Alexander. Lyttle, 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:-
I mount two levers with magnetized steel armatures so that their
armatures shall be within reach of the magnetic influence of a set of
electro-magnetic coils. The armatures are so arranged that a current
circulating through the coils which will attract one armature shall
Each armature is, however,
tend to drive the other armature away.
only free to move in one direction, so that a current which will attract

page_text: one will not move the other, except in the event of using the balanced
back stop described below. One of these levers, to be called number 1
lever, engages at its end furthest from the coils and axis of motion
into the ratchet cut teeth of a metal disc or plate. A metal spring
catch or detent also engages into the teeth of the same disc. The
disc moves on an axis and is retained when at rest by a spiral or other
spring pressing back a projection on its side or circumference against
a stop pin. When number 1 lever makes, say, four strokes the disc
is drawn four teeth forward. If the detent catch is now forced back
from the disc, the latter by the action of the spiral spring flies back
till it strikes against the stop pin from which it started. This function
of liberating the detent by forcing it back is effected by the lever
number 2 of the aforesaid levers when that lever is attracted.
A lever of light construction, to be called number 3 lever, working
on an axis and in a plane at right angles to that of the lever number 2,
is first pressed into motion, either by a simple bell-crank movement
or in the following manner before the number 2 lever liberates the detent
catch. At right angles across the end of number 2 lever and in the
plane of its motion is fixed a piece of flat spring which when the
lever moves rubs against a small friction roller fixed on the axis of
number 3 lever, and so makes that lever rise or fall. There is a hole,
slot, or other recess in the face of the ratchet disc into which when the
disc is in proper position the pin or free end of the number 3 lever
can pass. This movement of the number 3 lever I shall designate
"threading," from its bearing some resemblance to the action threading
a needle. When the hole or opening in the disc is brought over the
point of the number 3 lever at the tenth ratchet tooth or tenth move-
ment of number 1 lever " threading" is effected by simply reversing
the current, and so bringing number 2 lever into action.
When "threading" is effected the number 3 lever has moved through
an angle sufficient to enable it either to liberate a clockwork escape-
ment or to complete a local battery circuit so as to ring a trembler or
other alarum bell. Immediately on the cessation of the reversed or
"threading" current the number 3 lever falls back by the action of
the friction spring of number 2 lever. When the disc is advanced, so
the "threading" position, the
as to move the hole in the disc from
friction spring at the end of number 2 lever merely slips over the
friction wheel on the axis of number 3 lever, or the bell crank of that,

page_text: When
lever moves, pressing that lever first against the face of the disc,
and then, in its further advance, pressing out and so liberating the
detent or ratchet catch. The disc is then free to fly back to its stop
pin. If lever number 1 is provided with a click tooth or toe for
engaging into the ratchet teeth of the wheel lever, number 2 must
then be provided with a spur so adjusted as to tilt the click tooth out of
gear when lever number 3 is driven home by lever number 2.
levers numbers 1 and 2 move in parallel planes they may be fitted
with a transverse lever working on an axis between them. One end
of this cross lever should intervene between lever number 2 and its
back stop, such back stop being arranged precisely as in the Morse
printer telegraph. The other end of the cross lever should be free
and should itself carry the back stop adjustment of lever No. 1. This I
call a balanced back stop because when number 2 lever moves then
the cross lever tilts up and allows number 1 lever to go clean out of
gear with the ratchet wheel.
I use this arrangement as the means of calling any one telegraph
station without disturbing any of the others as follows: At one station
of the series in circuit I adjust the ratchet disc of this alarum so that
the "threading" can be effected after, say, the tenth stroke of number 1
lever. The next station instrument is adjusted for "threading" only
The third
to take place at the eleventh stroke of number 1 lever.
station instrument will "thread" only at the twelfth stroke of number 1
lever and so on. It is evident that the movements of number 1 lever,
which will prepare for threading at the first station, will not suffice
for that purpose at any of the others, and that if after sending ten
currents to move the number 1 lever of each instrument in circuit the
current is reversed, threading, and consequently ringing the alarum
will result at the first station only.
When an electrical alarum bell is to be set in motion instead of a
clockwork alarum any kind of electrical alarum can be used, but I
prefer one arranged as follows for continuous ringing when
started:
once
In a line with the vibrating armature of a common electrical trembler
alarum I place a magnetized steel lever, moving on an axis and in the
same plane as the armature. Its arms are of unequal length, the shorter
one resting against the face of the free extremity of the aforesaid
vibrating armature. When, however, the vibrating armature is attracted

page_text: by the trembler coils it moves the short arm of the magnetized lever,
and so causes the longer arm of that lever to strike its end or pole
against a piece of iron or magnetized steel (with opposite polarity
at the point of contact). Once the magnetized lever is brought by
the vibrating armature into this position it of course clings in its new
position by the superior attraction at the end of its longer arm, and
at the latter point it becomes the channel for the current from a local
battery which will keep the trembler bell ringing till the long arm
of the magnetized lever in question is pushed back and the circuit is
so broken. This magnetized lever may also be a simple crank, and
whatever its form it may stand in any convenient position, provided
it is tilted over easily by the first movement of the vibrating armature.
The short arm should have opposite polarity to that developed in the
nearest bell coil. The circuit closed by number 3 lever to ring the
electric bell should be a branch of the same battery circuit as that which
is to be closed by the action of the vibrating bell armature and its
magnetized lever with the unequal arms.
Of course this arrangement of auxiliary magnetized lever to be moved
by the vibrating armature can be applied to any ordinary railway or
other alarums without the foregoing "threading" mechanism, and in
that case the line current commences the alarum and the local current
keeps it up through the circuit of the new auxiliary or relay magnet
lever.
The aforesaid lever armatures, designated numbers 1 and 2, which
work the ratchet disc, may also be made to serve for telegraph signalling
by causing them to actuate the hammers of two bells or other sounding
media, either by direct impact or by acting as relay levers for laying
on a local current by which to work an acoustic telegraph like that
well known as "Bright's bell telegraph."
A single needle telegraph can also be worked by means of the same
numbers 1 and 2 levers by arranging a single needle pointer so that
it shall be tilted over to the right or left accordingly as either lever
is brought into play. If a vertical needle pointer is arranged so that
it stands on an axis placed above the ends of the armature levers
numbers 1 and 2, and with a cross arm of thin spring metal which
shall stand over and so close to the end of each lever hook as to
almost touch, any movement of a lever hook will, of course, cause the
needle to tilt over like the cock of a balance. If the needle is kept

page_text: vertical by a weak spring arrangement, or by the attraction of a magnet,
it will be less likely to oscillate when recovering its vertical position
and can be regulated to obviate the effect of disturbing currents.
Having now described the nature of my Invention, and some of the
best means known to me for carrying it into effect, I wish it to be
understood that what I claim is,―
Firstly. The threading" arrangement as described, to act as a
distinctive telegraph call by starting a bell at the particular station
called.
Secondly. The combination of this call arrangement as described,
with the means of signalling by sound or sight for ordinary telegraphic
purposes.
Thirdly. The means specified for laying on by a telegraph line
current a continuous and independent local current to an ordinary
trembler electric bell.
In witness whereof, I, the said William Alexander Lyttle, have
hereunto set my hand and seal, this Seventh day of December, in
the year of our Lord One thousand eight hundred and sixty-
nine.