IMPROVEMENTS IN m
Year: 1873

page_text: LETTERS PATENT to Sir William Thomson, Knight, of Glasgow
College, Doctor of Laws and Professor of Natural Philosophy in the
University and College of Glasgow, and Fleeming Jenkin, of No. 5,
Fettes Row, Edinburgh, for the Invention of "IMPROVEMENTS IN
m
PROVISIONAL SPECIFICATION left by the said Sir William Thomson
and Fleeming Jenkin at the Office of the Commissioners of Patents,
with their Petition, on the 12th June 1873.
We, Sir WILLIAM THOMSON, Knight, of Glasgow College, Doctor of
Laws and Professor of Natural Philosophy in the University and College
of Glasgow, and FLEEMING JENKIN, of No. 5, Fettes Row, Edinburgh,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
TELEGRAPHIC APPARATUS," to be as follows:-
:—
Our improvements relate to the apparatus by which telegraphic
signals are sent and received, the object of the Invention being to
increase speed and to diminish the risk of error.

page_text: We effect our object by constructing improved sending apparatus, by
which we can with greater ease and certainty make the contacts required
for many of the compensated signals described in our joint Patent, No.
2047, in the year 1860, and in the Patent No. 329, in the year 1858,
taken out by one of us, and in the Patent No. 1784, in the year 1865,
taken out by one of us in conjunction with Mr. Varley, and in Patents
No. 2, and 3483, granted to the said Mr. Varley, and we introduce
an improvement in the receiving apparatus described in the Patents
taken out by one of us, No. 2147, in the year 1867, and No. 252, in the
year 1871, by which it is simplified and rendered more suitable for use
on land lines or short submarine lines where great sensibility is not
required.
860
Our improvement in the receiving instrument now known as the
siphon recorder consists in binding a small brush, such as is used for
very fine water-colour painting, to the end of the siphon, which will then
paint the signals on the paper, leaving a continuous trace without the
spurting of fine drops by electricity. The same end is attained by
grinding the end of the siphon smooth and parallel to the paper. The
siphon thus prepared will indicate such currents as are sent on land
lines of moderate length. This improvement renders unnecessary for
these cases the mouse mill and electro-static arrangements hitherto used
with the siphon recorder.
In order to send the signals we prepare the message in type or in
punched paper. When punched paper is used we employ holes on the
right and left hand sides for positive and negative signals in a well
known manner, and in some forms we employ a row of central holes.
When type is used we employ similarly a row of right and left hand
projections for positive and negative signals, and in some forms a central
row of projections for spaces.
When we desire to send the curb key contacts or similar groups of
contacts described in the Patent dated July 6th, 1865, No. 1784, we use
the holes or projections to throw the line into connection with the
mechanism used to make the dot contacts, dash contacts, and space
contacts if these are used according to the hole punched or type set, and
we do this in such a manner that the beginning and end of each group
of contacts required for a signal does not depend on the perfect spacing
of the holes or type; the hole or projection determines which contact or

page_text: group of contacts shall be made, but the length and arrangement of
each group of contacts depends only on the cam or other arrangement
used to make the contacts; thus any required group of contacts may be
sent by one and the same strip of paper and by the same machine. We
effect this by causing the hole or projection to throw a portion of the
machinery connected electrically with the line into mechanical gear
with the particular cam or other mechanism required to be in action.
The commencement of the mechanical interlocking is not limited to
one exact position of the cam, but will take place correctly though the
types or holes be not very uniformly spaced. The electrical contacts
determined by the cam or mechanical gearing begin at a perfectly
definite point, which is exactly that at which the group of contacts
determined by the cam or mechanical gearing previously in use end.
We employ a new mode of adjusting the lengths of the contacts made
by cams, so that one projection on one cam may be made use of to give
a succession of contacts of any length; this we effect by making the
length of the contact pieces which rest on the cam adjustable so that if
the projection wire ½ inch long, and the contact piece resting on it ¾
inch long, the length of contact would be that given by a cam 1 inch
long, and a sharp contact edge resting on it.
Instead of making the length of one contact piece adjustable we effect
the same object by a succession of two or more contact pieces making the
same contact, and one beginning its function before the previous one
leaves off; the distance between these contact pieces can also be
adjusted.
Where less perfect compensation is required than is given by the above
arrangement we allow the projections of the type to make the contacts
required by moving a succession of springs, and adjust the relative
length of the groups of contacts by the mode above described, so that a
single projection of the type will send a whole series of curb key contacts
precisely as one projection on the cam will send the group of contacts.
When we employ type we prefer to use a wheel or endless band, and
set it up by touching keys on the wheel or band when in motion; the
message is obliterated by suitable rollers after the contacts have been
made, and each part of the wheel or band comes round to the operator
ready to have the message set up. In this plan there are no loose types,
and a whole letter or more than one letter where these are simple can

page_text: be set up by one motion of the hand or hands as a chord is played on
the piano; this saves labour in keying and obviates all necessity for paper.
Keys may be arranged so as to be worked in exactly the manner
practiced with the present positive and negative keys, and so that each
motion sets one type, but we prefer the simple direct action. The wheel
may be driven by a treadle or otherwise.
When we employ punched paper, which is necessary where the speed
required is so great that the above ring sender cannot be manipulated,
we use an improvement in the puncher described in the Patent No. 252,
in the year 1871, this improvement consists in a plan by which the fly
wheel there described is rendered unnecessary, the crank being carried
past the dead points by a spring which acts as an alternative accumulator
and restorer of the work employed to turn the crank.
The final position of the roller drawing forward the paper is determined
by a catch which secures the roller at the proper point of its revolution,
the catch being lifted out of gear by a cam when the roller is required
to be free.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Sir William Thomson and Fleeming Jenkin in
the Great Seal Patent Office on the 12th December 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, Sir
WILLIAM THOMSON, Knight, of Glasgow College, Doctor of Laws and
Professor of Natural Philosophy in the University and College of
Glasgow, and FLEEMING JENKIN, of No. 5, Fettes Row, Edinburgh, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of June, in the year of our
Lord One thousand eight hundred and seventy-three, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said Sir William Thomson and Fleeming Jenkin,
Her special license that we, the said Sir William Thomson and Fleeming
Jenkin, our executors, administrators, and assigns, or such others as
we, the said Sir William Thomson and Fleeming Jenkin, our executors,
administrators, and assigns, should at any time agree with, and no

page_text: 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
TELEGRAPHIC APPARATUS," upon the condition (amongst others) that we,
the said Sir William Thomson and Fleeming Jenkin, our executors or
administrators, by an instrument in writing under our, or their hands and
seals, or under the hand and seal of one of us or them, 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 we, the said Sir William Thomson, and
Fleeming Jenkin, do hereby declare the nature of the 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,
that is to say :-
Our improvements relate to the apparatus by which telegraphic signals
are sent and received, the object of the Invention being to increase speed
and to diminish the risk of error.
We effect our object by constructing improved sending apparatus by
which we can with greater ease and certainty make the contacts required
for many of the compensated signals described in our joint Patent,
No. 2047, in the year 1860; and in the Patent No. 329, in the year 1858,
taken out by one of us; and in the Patent No. 1784, in the year 1865,
taken out by one of us in conjunction with Mr. Varley; and in Patents
No. and 14, granted to the said Mr. Varley; and we introduce.
an improvement in the receiving apparatus described in the Patents.
taken out by one of us, No. 2147, in the year 1867, and No. 252 in the
year 1871, by which it is simplified and rendered more suitable for use
on land lines or short submarine lines where great sensibility is not
required.
200
53
Our improvement in the receiving instrument now known as the
siphon recorder consists in binding a small brush such as is used for
very fine water colour painting to the end of the siphon, which will then
paint the signals on the paper, leaving a continuous trace without the
spurting of fine drops by electricity. The same end is attained by

page_text: grinding the end of the siphon smooth and parallel to the paper. The
siphon thus prepared will indicate such currents as are sent on land lines
of moderate length. This improvement renders unnecessary for these
cases the mouse mill and electro-static arrangements hitherto used with
the siphon recorder.
In order to send the signals we prepare the message in type or in
punched paper. When punched paper is used we employ holes in the
right and left hand sides for positive and negative signals in a well
known manner, and in some forms we employ a row of central holes.
When type is used we employ similarly a row of right and left hand
projections for positive and negative signals, and in some forms a central
row of projections for spaces.
When we desire to send the curb key contacts or similar groups of
contacts described in the Patent dated July 6th, 1865, No. 1784, we use
the holes or projections to throw the line into connection with the
mechanism used to make the dot contacts, dash contacts, and space
contacts if these are used according to the hole punched or type set, and
we do this in such a manner that the beginning and end of each group
of contacts required for a signal does not depend on the perfect spacing
of the holes or type. The hole or projection determines which contact
or group of contacts shall be made, but the length and arrangement of
each group of contacts depends only on the cam or other arrangement
used to make the contacts. Thus any required group of contacts may
be sent by one and the same strip of paper and by the same machine.
We effect this by causing the hole or projection to throw a portion of
the machinery connected clectrically with the line into mechanical
gear with the particular cam or other mechanism required to be in
action.
The commencement of the mechanical interlocking is not limited to
one exact position of the cam, but will take place correctly though the
types or holes be not very uniformly spaced. The electrical contacts
determined by the cam or mechanical gearing begin at a perfectly
definite point, which is exactly that at which the group of contacts
determined by the cam or mechanical gearing previously in use end.
We employ a new mode of adjusting the lengths of the contacts made
by cams so that one projection on one cam may be made use of to give

page_text: The final position of the roller drawing forward the paper is de-
termined by a catch which secures the roller at the proper point of its
revolution, the catch being lifted out of gear by a cam when the roller
is required to be free.
Our improvement in the recorder requires no further description than
that given above.
We will first describe more fully one portion of our Invention which
we call the ring sender, consisting of the wheel or endless band above
mentioned, in which type is set up by touching keys on the wheel when
in motion.
Figures 1 and 2, Sheet 1, shew the front and side elevation of one
form of the ring sender. The wheel or ring A, A, is driven by a treadle B
through spur wheel gearing at C and D and E, the ring may be driven
at a uniform speed of about 2 revolutions per minute to send 20 words
per minute. On the periphery of the ring A are arranged about 130 uni-
formly spaced and similar type keys "a, a, a, etc;" each key can slide
in V grooves, Figure 3, Sheet II. in a direction parallel to the axis of
the wheel A. Each key has a projection at the centre of its length which
serves to make the necessary contacts in one of the ways to be hereafter
described. Each key has a little head at each end which may be made
of vulcanite, and by which it can be pressed backwards or forwards by
the hand while being set. When the projection of a is opposite the
centre of the groove H in the periphery of A, no signal is produced at
the further end of the line. When the projection of a is at the right
extreme of its range a dot or positive signal is sent into the line, and
when at the left extreme of its range a negative signal is sent which for
brevity we may call a dash, although it is of equal length with the dot,
the projection in fact plays a part analogous to the well-known holes
punched in a strip of paper by which spaces, dots, and dashes are pro-
duced, the central row of holes giving spaces, the holes on the one side
positive dots, and the holes on the other side negative dots, which we call
dashes.
The type is set up by the operator with both hands, one on each side
of the ring A. As the periphery of the wheel comes up to him he
finds all the keys in their central position, having been brought into this
position by passing the rollers R and R', then to send the letter a with
one finger of the left hand he presses back a type and simultaneously

page_text: a succession of contacts of any length. This we effect by making the
length of the contact pieces which rest on the cam adjustable, so that if
the projection were ½ inch long and the contact piece resting on it
3 inch long the length of contact would be that given by a cam 1'/, inch
long, and a sharp contact edge resting on it.
Instead of making the length of one contact piece adjustable we effect
the same object by a succession of two or more contact pieces making
the same contact, and one beginning its function before the previous one
leaves off. The distance between these contact picces can also be
adjusted.
Where less perfect compensation is required then is given by the
above arrangement we allow the projections of the type to make the
contacts required by moving a succession of springs, and adjust the
relative length of the groups of contacts by the mode above described,
so that a single projection of the type will send a whole series of curb
key contacts precisely as one projection on the cam will send the group
of contacts.
When we employ type we prefer to use a wheel or endless band, and
set it up by touching keys on the wheel or band when in motion. The
message is obliterated by suitable rollers after the contacts have been
made, and each part of the wheel or band comes round to the operator
ready to have the message set up. In this plan there are no loose types,
and a whole letter or more than one letter where these are simple can
be set up by one motion of the hand or hands as a chord is played on
the piano. This saves labor in keying, and obviates all necessity for
paper. Keys may be arranged so as to be worked in exactly the manner
practised with the present positive and negative keys, and so that each
motion sets one type, but we prefer the simple direct action. The wheel
may be driven by a treadle or otherwise.
When we employ punched paper, which is necessary where the speed
required is so great that the above ring sender cannot be manipulated,
we use an improvement in the puncher described in the Patent No. 252,
in the year 1871. This improvement consists in a plan by which the
fly wheel there described is rendered unnecessary, the crank being
carried past the dead points by a spring which acts as an alternative
accumulator and restorer of the work employed to turn the crank.

page_text: with one finger of the right hand he presses back the following type in
the opposite direction. If the letter a is to be followed by the letter S he
lets one type pass unmoved and then presses the three following types
back with his left hand. In this way one or more letters can be set up
at once by a simultaneous motion of the two hands as a cord or cords
are played on the piano; the advantage of the instrument consists in
the accurate spacing which it gives, together with simple methods of
producing the groups of contacts required for perfect signals through
long submarine lines. These contacts may be produced in three distinct
ways,―
Firstly, we use cach type to produce a series or group of contacts by
allowing the projection of the type to make electrical contact succes-
sively with a series of adjustable springs ranged with the contact pieces
one after the other, as shewn in Figure 7, where three adjustable
springs b, c, d, having adjustable contact pieces b¹, c, d, are ranged so as
successively to make contact with the projection of a. b and d may bo
connected with the positive pole of a battery, and c with the negative
pole of an equal battery; the other poles being to earth; then if the
projection a is in connection with the line and otherwise insulated, the
three springs as the type passes under them, will send the group of three
contacts required for the curb key described in the Patent No. 1784,
A.D. 1865, granted to Messrs. Thomson and Varley, the length of the
contacts made by b, c, and d, can be adjusted by adjusting the distance
between the pairs of conical nuts at b', c¹, and d; the springs which
can be secured in their places by pinching nuts b, c, and d, must be so
adjusted longitudinally that the first contact made by 6¹ coincides with
the last made by d¹, as a succession of keys pass under the contact
pieces, and moreover the last contact of 6 must coincide with the first
of c¹, and the last of c¹ with the first of d¹; it is clear that the same
plan might be adopted either to send single contacts or series of four or
five, or more contacts with the same or different batteries for each
signal. Adjustable pairs of springs opposite one another, and electrically
connected may be used instead of the adjustable contact pieces or conical
nuts. The ring sender may be used without our plan of giving varying
lengths of contacts by a single projection, or this plan of making groups
of carefully adjusted contacts by a single projection may be applied to
any cam.

page_text: sender differs from the first only in avoiding rubbing contacts, and is
shewn in detail in Figures 3, 4, 5, and 6, Sheets I. & II. The springs
b and c, with their adjustable contact pieces b and c, make the two
contacts for the dash. The spring e makes the earth contact for spaces,
and the springs ƒ and g make the two contacts for a dot, the series of
five springs being adapted to make the contacts described in the Patent
No. 2047 granted to us in 1860, and more particularly indicated in
Figure 10, Sheet 1 of that Patent. The contact is made not between
the projection a and the contact spring, but between a second pair of
springs, as at b₂, b., or C2, C3, Figure 3, insulated in the usual way. The
terminals of these are shewn at t, t, one being connected to the battery,
and the other to the line. The longitudinal positions of each group of
springs can be adjusted by the screws which move the whole system in
small V grooves v, Figure 5. The lengths of each contact can be
adjusted by the conical nuts as before.
When the contacts are properly adjusted, the beginning of the con-
tacts made by b, e, and f must coincide, that is to say, if the projection
a were prolonged so as to work all three instead of one all three contacts
would begin together. Similarly the end of the contacts made by c, e, g,
must coincide, and the end of these contacts must coincide with the
beginning of the contacts made by b, e, and f, due to the next key;
moreover, the contact pieces of b and c must be so adjusted that the
contact made by b is a little longer than that made by c, and that the
contact made by c begins exactly where that made by 6 ends. Again,
the contact pieces of ƒ and g must be so adjusted that the contact made
by f is a little longer than that made by g, and that the contact made by
g begins exactly where that made by fends. When this has been done
b and c will send dashes, fand 9 will send dots, and e will send spaces,
the motion of the type being in the direction shewn by the arrows.
is easy to adjust the relative lengths of the contacts made by b and c, or
fand g, so as to suit any particular line.
It
The groups of contact springs are all attached to a bracket F, which
can be detached by unscrewing the single nut G for the purpose of
examining or adjusting the contacts. The bracket when replaced
occupies a position perfectly determined by three pins f,f,f, resting in a
hole and a slot; and on a plane, respectively, two brackets F and F¹,
Figure 1, are provided, so as to give a spare set of contacts which may
be differently adjusted.

page_text: by a spring or weight, and the speed is controlled by a suitable governor.
There are two similar levers b, a, and 61, a¹, on the two sides of the
wheel A, A¹, which is fast on the shaft O. The two halves of the
wheel A, A¹, are insulated. These levers are hinged on the axis g, they
are insulated from one another, and the ends b, b¹, are insulated from the
axis g. Two similar insulated cams G, G¹, on opposite sides of A, A',
allow the ends b, b¹, to rise at one portion of the revolution of the
wheel A. Only one cam G is shewn in the Drawings, the second being
precisely similar to it. The ends b, 61, of the levers tend to rise in
consequence of the constant pressure of the springs m, m², Figure 4.
When a hole passes under the end a of the lever, the end is free to
rise, but when solid paper passes under a the end 6 does not rise, the
gearing between the axes N and O is such that the passage of the
punched holes under a corresponds to the passage of the recess in the
cams G past the end b. Thus when a hole passes the end a, corresponding
to a dash, the end 6 tends to rise, whilst the solid paper under 6¹ prevents
b₁ from rising. Similarly, when a hole passes the end a¹ corresponding to
a dot the end b₁ tends to rise, while the solid paper prevents 6 from rising.
Two openings fand f₁ are made in the periphery of the wheel A, A³,
and when the ends 6 or b₁ tend to rise they tend to lift the ends of the
two springs E, and L₂ through for f₁. The passage of a dash hole
under a thus causes E, to be lifted through f, whilst L, remains
depressed. On the contrary the passage of a dot hole under a₁ causes L
to be lifted through f₁, leaving E, depressed. When either L, or E₂ have
been lifted they are caught by the projecting rim of A or A₁, and kept up
during a whole revolution of the shaft O. The ends 6 or 6¹ are however
depressed by the cams G or G¹, immediately after L² or E³ have been
caught by the rim, and a or a¹ are thus lifted out of the hole in the
paper, so as not to impede the progress of the paper. If a succession of
dot holes occur the spring L³ remains up and Es down. If a succession
of dash holes occur the spring L³ remains down and E up, when a dashi
is followed by a dot the instant at which the spring E³ falls, and that at
which L² rises to its full height depends not on the exact position of the
hole in the paper but on the passage of the apertures f. f₁, and the
changes in the position of the springs can consequently only occur at a
perfectly uniform intervals, when the shaft O revolves uniformly.
1
The spring E is in connection with the earth through the terminal E;
the spring L is in connection with the line through the terminal L.

page_text: .
When either L'or E' are up they are in connection with an insulated
bar or junction piece B, B1, B2, B3, B4, B'; when they are down they are
in connection with an insulated bar or junction piece F, F³. The two
cams K, K', each insulated serve to make connections between the poles
of two batteries and the bars B and K. At the instant when E* rises
and L³ drops the cam K lets up the end of the spring C³ in connection
with the copper pole of a battery, while the cam K¹ presses down the
spring Z in connection with the zinc pole, the same battery thus putting
copper to earth through the terminal E, and zinc to the line through B
and L. After rather more than half a revolution the cams K and K'
put the line to copper and earth to zinc, and this action will continue so
long as dash holes continue to pass under a. When however a dot hole
passes under a the positions of L³ and E' are reversed; then the cam K
puts first copper to line for a longer period, and then to earth for a shorter
period; while K¹ puts zinc first to earth for a longer period and then to
the line for a shorter period. If no hole passes under either a or a¹ both
6 and 6¹ remain depressed, and L³ and E² remain in contact with F', thus
the line remains to earth, and the cams K and K¹ put each pole of the
battery alternately to earth, producing no effect on the line.
The series of changes is most easily followed by means of the Diagram,
Figure 7. The cams K and K¹, as described and shewn are suitable to
send the signals already described in connection with the ring sender,
and particularly illustrated by Figure 10, Sheet 1, of the Patent No.
2047, A.D. 1860; but the cams may be arranged to send any groups of
contacts, it being clear that the reversal of the position of the springs L'
and E³ will reverse the sign of the signal sent by the cams, and that the
length of each signal is measured by one revolution of the cams. The
lengths of the contacts made by the cams or by projections on the cams
may be adjusted by the same means as that which has already been
described in connection with the type of the ring sender.
The several bars and springs C, Z, L, B, and F are insulated from one
hhain attached to a muloonito clah M
We punch the paper employed in the paper automatic transmitter by
means of the puncher shewn in Figures 9, 10, and 11, Sheet IV., repre-
senting an improved form of the puncher described in the Patent No.
252, A.D. 1871, granted to one of us.

page_text: Figure 9 is a side elevation; Figure 10, a plan; and Figure 11, an
end elevation. Three keys A, B, C, punch the holes by pressing on
three dies a, b, c. What in the former Patent was termed the revolver
shaft is shewn at R; this shaft is turned by a connecting rod D and
crank E, worked by a lever which rocks when any of the three levers
A, B, or C are depressed.
The revolution of the revolver shaft past the dead points is produced
by the spring G, which alternately stores up the work done by the
operator and restores it to the mechanism by turning the shaft R. A
snail K works with the spring H to force it back, and the spring G is
forced back by the cams F, F; we place these cams on the shaft instead
of the connecting rod. The spring H has a V at the end, which acts as
a clutch, determining by its interlocking with the wheel W the exact
point at which paper roller T on the axis S shall stop. The revolver
shaft during a portion of its revolution drives the paper roller by the
same means as has been described in the above named Patent, No. 252,
1871, so that the paper stops and starts gradually.
In connection with the puncher we claim only the improved arrange-
ment of the parts as shewn in the Drawing, which makes the instrument
WILLIAM THOMSON.
(L.S.)
FLEEMING JENKIN.
(L.S.)