Improvements in and connected with Telegraphy.
Year: 1899

page_text: Date of Application, 6th Mar., 1899
Complete Specification Left, 8th Jan., 1900-Accepted, 6th Mar., 1900
PROVISIONAL SPECIFICATION.
Improvements in and connected with Telegraphy.
▲ communication from abroad by ALBERT CUSHING CREHORE, of Hanover,
Grafton County, State of New Hampshire, United States of America, Pro-
fessor of Physics and GEORGE OWEN SQUIER, of Fortress Monroe, Elizabeth
City County, State of Virginia, United States of America, Lieutenant in
the United States Army.
I, WILLIAM LLOYD WISE, of 46, Lincoln's Inn Fields, in the County of London,
Consulting Engineer and Chartered Patent Agent, do hereby declare the nature
of this invention to be as follows:-
In the Provisional Specification of my application for Letters Patent No. 4931
of 6 March 1899 there is described apparatus which by proper modification may
be made to furnish and to impress upon an electric circuit semi-cycles of electro-
motive force differing in value or amount as well as in sign or polarity for a
purpose to be hereinafter described.
Figs. 1, 2 and 3 of the accompanying drawings represent in skeleton and
diagrammatically such apparatus modified for the purpose mentioned.
Fig. 4 shows graphically the ordinary arrangement and polarity of pulses
of electromotive force impressed in sending a message by the International code.
Figs. 5 and 6 illustrate graphically the manner in which the elements of time
and polarity are combined with the differences of electromotive force to make
up a code that may be used with the apparatus shown in Figs. 1, 2, and 3.
In Fig. 1 four transmitter terminals or brushes like D1, D2 are shown instead
of two only. Electromotive forces of different value from those furnished at 2, 3
are furnished at 1, 4 by connecting 1, 4 with the circuit of coils 61, 2 through
adjustable impedances R1, R2 in the manner shown.
The transmitting tape or paper has four parallel lines of perforations, one for
each of the brushes, thereby permitting the electromotive forces present at
the brushes, two of one sign but different value and two of the opposite sign and
also different value from one another, to be impressed upon the circuit. The
potential difference at the terminals or brushes connected to R1, R2, may obviously
be anything different from that furnished at the brushes connected directly to
the coils 61, 62.
The different electromotive forces or potentials may be obtained without using
impedances by employing additional armature coils a, a, as indicated in Fig. 2,
such coils being adapted to develop the required electromotive forces of greater
or less value than those developed by the coils 61, 62. In this case separate pole
changers C, C would be used for each value of electromotive force as clearly
shown.
Instead of using separate coils the different electromotive forces when less
are chosen may be had by tapping the coils 61, 2, as indicated in Fig. 3, the two
separate commutators being employed as before.
The different values of the electromotive force might be obtained from coils

page_text: operating in different magnetic fields and other variations in the character of
the generating devices are obviously permissible.
It is not necessary that the potentials or electromotive forces on brushes or
terminals 1, 4 should be equal to one another, nor is it necessary that the
potentials at the brushes 2, 3, should be equal to one another.
The apparatus modified as in Figs. 1, 2, and 3 is especially useful in cable
telegraphy, wherein the practice has heretofore been to impress upon the cable
suitable pulses by an electromotive force sometimes positive and sometimes
negative and at the desired times or intervals according to the code employed,
positive pulses of one polarity being ordinarily used for the dashes of an alphabet
or code and opposite pulses for the dots of the alphabet, the messages being read
at the receiving end by the deflections or to-and-fro movement of an arm, stylus
or other device, either directly by observed movements thereof, or else by causing
said device to make a sinuous mark upon a recording sheet or strip. In this
system the times or intervals at which the deflections occur and the direction of
the deflections or movements of the instrument enable the characters of the code
to be distinguished. The minimum number of pulses which it is necessary to
employ in sending a message is then practically determined by the fact that the
two elements only of time and polarity are employed. No attempt is made in
this system to employ a difference in the magnitude of movement of the receiving
instrument.
By using the apparatus shown in Figs. 1 and 2 this difference of magnitude
may be compounded or made to co-exist with differences of direction or polarity
and intervals of time and the total number of pulses which it is necessary to
employ to send all the characters of any code may be largely diminished.
In code telegraphy a siphon recorder is ordinarily used as receiver since that
gives a superior means for reading the variations in the strength and direction of
the received impulses. In the present systems time and polarity are alone used
and interpreted by such a receiver, but the instrument furnishes a means for
indicating differences in magnitude or strength of the current as well, the
amplitude of deflection of the recording siphon showing whether the current wave
received is of one or another strength or value. The additional gain by com-
pounding the time, polarity, and strength may be understood from a comparison
between the present cable or international code in which time and polarity alone
are used and a similar code as used with the improved apparatus as shown in
Figs. 1, 2 and 3.
In the diagrams Figs. 4, 5 and 6, the sinuses or semi-waves projecting from
the horizontal lines indicate pulses of electromotive force as impressed upon
the circuit according to the code employed, the polarity of the impressed electro-
motive forces being shown by the direction in which the sinus is developed or
projects from the normal or horizontal line and the difference in value or strength
of the impulse being shown by the difference in the height of amplitude of each
curve.
Fig. 4 indicates the international code by the collocation and polarity of the
elementary pulses of impressed electromotive forces. In this it will be seen
that there is no difference in the value or strength of the electromotive force or
potential.
In Fig. 5 differences in value or strength of electromotive force in addition
to time and polarity are shown.
Examination of the conditions indicated in Fig. 4 shows that according to the
law of combination and using four as the maximum number of pulses for any
character, there are thirty combinations using four or less pulses each. Twenty
six of these are used for the present alphabet and four are not needed. Twelve
characters have four pulses, eight have three, and four have two, whilst two
characters have one pulse each. With this new system using the three elements
of time, polarity, and electromotive force or magnitude difference, by the law
of combinations eighty-four characters are possible, but as only twenty six

page_text: of these are required it is evident that an alphabet or code with twenty-six
characters may be constructed to have, as indicated in Fig. 5, four characters
with one pulse cach, sixteen with two pulses, and six with three pulses.
In the alphabet shown in Fig. 5 the only characters which have pulses of the
same polarity occurring in succession are eight of the combinations of two
pulses per letter, since when three pulses are employed combinations sufficient
in number to make up the alphabet and which will have their successive pulses
alternating in polarity may be chosen from the sixty-four possible ones of three
pulses each. But by varying the selection and increasing slightly the number
of characters which have three pulses while somewhat diminishing the number
which have two pulses only, it is possible to have a code in which no two successive
waves or pulses for any character shall be of the same polarity and at the same
time to retain that characteristic of the invention which involves the combination
as already explained of the three elements of time, polarity, and differences of
electromotive force or impressed potential. The value of this will readily be
appreciated from the following consideration.
When two successive waves of the same polarity are sent into a cable, the
current does not return to the zero value, and as a consequence there is a
piling up effect which tends to displace the recording siphon off toward the
edge of the paper, and make it harder to read because there is a little distinction
in the record between the successive pulses, they being both merged into one
large one. The reason for this is clearly brought out when this fact is
considered. If a continuous streain of pulses of the same polarity is sent into
the cable in succession, the record shows a wavy line which starts from the centre
of the receiving tape and oscillates about a medial line which is displaced quickly
or at a sharp angle to one side but gradually comes back to the centre of the
tape. After the record has returned to the centre of the tape (the return being
due to the presence of a condenser in the line) its appearance cannot be dis-
tinguished from the records produced by a simple sine wave alternating current.
In fact the same record could be made in two ways, first as above, and second
by using an alternating current of double the frequency of the above.
The conclusion is that the use of pulses of the same polarity successively is
equivalent in record to an alternating current of double the frequency and that
as the first signals to become illegible are those having two successive
waves of the same polarity, the use of characters produced by a succession of
pulses of the same polarity is detrimental to speed and that an alphabet having
no successive waves of the same polarity is superior to one having them, in
legibility at the receiver. A much greater speed of transmission is therefore
allowable before the limit is reached.
This advantage may be secured by selecting from the possible combinations
those combinations only of three or less pulses in which the successive pulses
alternate in polarity. Twenty-eight of these exist in the eighty-four com-
binations which it is possible to produce by using one to three pulses for each
character varying in polarity as well as strength or amplitude of impressed
electromotive force or potential. In other words more than enough exists to make
a complete alphabet as indicated in Fig. 6. An evident relation exists between_
this last alphabet and the international alphabet.
In each of the cases Figs. 5 and 6 it is obvious that the letters of the alphabet
may be assigned to the various characters of the code according to the frequency
with which the letters occur in transmission, so as to give to the letters most
frequently used the least number of pulses.
Dated this Sth day of January 1900.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Chartered Patent Agent.

page_text: Improvements in and connected with Telegraphy.
A communication from abroad by ALBERT CUSILING CREHORE, of Hanover,
Grafton County, State of New Hampshire, U.S.A., Professor of Physics, and
GEORGE OWEN SQUIER, formerly of Fortress Monroe, Elizabeth City County,
State of Virginia, but now of Washington, District of Columbia, U.S.A.,
Captain in the United States Army
I, WILLIAM LLOYD WISE, of 46, Lincoln's Inn Fields, in the County of London,
Consulting Engineer and Chartered Patent Agent, do hereby declare the nature
of this invention and in what manner the same is to be performed to be particu-
larly described and ascertained in and by the following statement:-
In the Specification of my application for Letters Patent No. 4931 of 6 March
1899 there is described apparatus which by proper modification may be adapted to
furnish and to impress upon an electric circuit semi-cycles of electromotive force
differing in value or amount as well as in sign or polarity for a purpose to be
hereinafter described.
Figs. 1, 2 and 3 of the drawings accompanying my Provisional Specification
represent in skeleton and diagrammatically such apparatus modified for the
purpose mentioned.
Fig. 4 shows graphically the ordinary arrangement of and polarity of pulses of
electromotive force impressed in sending a message by the International Code.
Figs. 5 and 6 illustrate graphically the manner in which the elements of time
and polarity are combined with the differences of electromotive force to make
up a code that may be used with the apparatus shown in Figs. 1, 2, and 3.
In Fig. 1 four transmitter terminals or brushes 1, 2, 3 and 4, like the brushes
D and of the apparatus described in the aforesaid specification, are shown
instead of two only. Electromotive forces of different values from those furnished
at 2 and 3 are caused to be furnished at 1 and 4 by connecting 1 and 4 with the
coils and through adjustable impedances R' and R in the manner shown.
The transmitting tape or paper has four parallel lines of perforations, one
for each of the brushes, so that the electromotive forces present at the brushes
of which two are of one sign but of different values and two of the opposite sign
and also of different values from each other, can be impressed upon the circuit
in any desired order. The potential at the terminals or brushes connected to R' and
R2 may obviously have any suitable difference from that furnished at the brushes
connected directly to the coils b' and be.
The different electromotive forces or potentials may be obtained without using
impedances by employing additional armature coils and a¹, as indicated in
Fig. 2, such coils being adapted to develop the required electromotive forces of
greater or less value than those developed by the coils 61 and 62. In this case a
separate pole changer C or C¹ would be used for the electromotive forces of each
value, as clearly shown.
Instead of using separate coils, the different electromotive forces, when less are
chosen, may be had by tapping the coils 61 and 62, as indicated in Fig. 3, the
two separate commutators C and C₁ being employed as before.
The electromotive forces of different values might be obtained from coils
operating in different magnetic fields, and other variations in the character of
the generating devices are obviously permissible.
It is not necessary that the potentials or electromotive forces on the brushes
or terminals 1 and 4 should be equal to one another, nor is it necessary that the
potentials at the brushes 2 and 3 should be equal to one another.
The apparatus modified as in Figs. 1, 2, and 3 is especially useful in cable

page_text: of au
telegraphy, wherein the practice has heretofore been to impress upon the cable
suitable pulses by an electromotive force sometimes positive and sometimes
negative and in the order and at the times required by the code employed, positive
pulses of one polarity being ordinarily used for the dashes
alphabet or code and opposite pulses for the dots of the alphabet, the
messages being read at the receiving end by the deflections or to-and-fro move-
ments of an arm, stylus, or other device, either directly by observed movements
thereof, or else by causing the said device or its equivalent to make a sinuous
mark upon a recording sheet or strip. In this system the times or intervals at
which the deflections or to-and-fro movements occur and the directions
of the deflections or movements of the instrument, enable the characters
of the code to be distinguished. The minimum number of pulses
which it is necessary to employ in sending a message is then practically deter-
mined by the fact that the two elements only of time and polarity are employed.
No attempt has heretofore, so far as my correspondents are aware, been made in
this system to employ a difference in the magnitude of movement of the receiv-
ing instrument.
By using the apparatus shown in Figs. 1 and 2 this difference of magnitude
may be compounded or made to co-exist with differences of direction or polarity
and intervals of time and the total number of pulses which it is necessary to
employ to send all the characters of any code may be largely diminished.
In cable telegraphy a siphon recorder is ordinarily used as the receiver since that
gives a superior means for reading the variations in the strength and direction of
the received impulses. In the present systems time and polarity are alone used
and interpreted by such a receiver, but the instrument furnishes a means for
indicating differences in magnitude or strength of the current as well, the
amplitude of deflection of the recording siphon showing whether the current wave
received is of one or another strength or value. The additional gain by com-
pounding the time, polarity, and strength may be understood from a comparison
between the present cable or international code in which time and polarity alone
are used and a similar code used with the improved apparatus shown in Figs. 1, 2
and 3.
In the diagrams Figs. 4, 5 and 6, the sinuses or semi-waves projecting from
the horizontal lines indicate pulses of clectromotive force as impressed upon
the circuit according to the code employed, the polarity of the impressed electro-
motive forces being shown by the directions in which the sinuses are developed
or project from the normal or horizontal line and the difference in value or
strength of the impulses being shown by the difference in the heights or ampli-
tudes of the curves.
Fig. 4 indicates the international code by the collocation and polarity of the
elementary pulses of impressed electromotive force. In this it will be seen
that there is no difference in the value or strength of the electromotive force or
potential.
In Fig. 5 differences in value or strength of electromotive force in addition
to time and polarity are shown.
Examination of the conditions indicated in Fig. 4 shows that according to the
law of combination, when four is the maximum number of pulses for any
character, there are thirty possible combinations of four pulses or less each.
Twenty-six of these are used for the present alphabet and four are not needed.
Twelve characters have four pulses, eight have three, and four have two, whilst
two characters have one pulse each. With the new system, in which the three
elements of time, polarity, and electromotive force or amplitude difference are
used, by the law of combinations eighty-four characters are possible
but as only twenty-six of these are required. it is evident that an alphabet
or code with twenty-six characters may be constructed to have as indicated in
Fig. 5, four characters with one pulse cach, sixteen with two pulses, and six with
three pulses.

page_text: In the alphabet shown in Fig. 5 the only characters which have pulses of the
same polarity occurring in succession are eight of the combinations of two
pulses per letter, since when three pulses are employed combinations which will
be sufficient in number to make up the alphabet and which will have their
successive pulses alternating in polarity may be chosen from the sixty-four
possible ones of three pulses each. But by varying the selection and increasing
slightly the number of characters which have three pulses while somewhat
diminishing the number which have two pulses only, it is possible to obtain a
code in which no two successive waves or pulses for any character will be of the
same polarity and at the same time to retain that characteristic of the invention
which involves the combination as already explained of the three elements of
time, polarity, and differences of electromotive force or impressed potential.
The value of this will readily be appreciated from the following consideration.
When two successive waves of the same polarity are sent into a cable, the
current does not return to the zero value, and as a consequence there is a
piling up effect which tends to displace the recording siphon toward the
edge of the paper, and make it harder to read because there is little distinction
in the record between the successive pulses, they being, both merged into one
large one. The reason for this is clearly brought out when this fact is
considered. If a continuous stream of pulses of the same polarity is sent into
the cable in succession, the record shows a wavy line which starts from the centre
of the receiving tape and oscillates about a medial line which is displaced quickly
or at a sharp angle to one side but gradually comes back to the centre of the
tape. After the record has returned to the centre of the tape (the return being
due to the presence of a condenser in the line) its appearance cannot be dis-
tinguished from the records produced by a simple sine wave alternating current.
In fact the same record could be made in two ways, first as above, and second
by using an alternating current of double the frequency of the above:
The conclusion is that the use of pulses of the same polarity successively is
equivalent in record to an alternating current of double the frequency and that
as the first signals to become illegible are those having two successive
semi-cycles of the same polarity, the use of characters produced by a succession of
pulses of the same polarity is detrimental to speed and that an alphabet having
no successive waves of the same polarity is superior to one having them, in
legibility at the receiver. A. much greater speed of transmission is therefore
allowable before the limit is reached."
This advantage may be secured by selecting from the possible combinations
those combinations only of three pulses or less in which the successive pulses
alternate in polarity. Twenty-eight of these exist in the eighty-four com-
binations which it is possible to produce by using one to three pulses for each
character varying in polarity as well as strength or magnitude of impressed
electromotive force or potential. In other words, more than enough exist to make
a complete alphabet as indicated in Fig. 6. An evident relation exists between
this last alphabet and the international alphabet.
In each of the cases represented by Figs. 5 and 6 it is obvious that the letters
of the alphabet may be assigned to the various characters of the code according
to the frequency with which the letters occur in transmission, so as to give to the
letters most frequently used the least number of pulses.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is-
1. The hereinbefore described improvement in telegraphy which consists in
impressing upon the circuit for characters of the code, successions of elementary
pulses of electromotive force, differing from one another as to potential and
polarity for different characters in the manner set forth, so as to combine different

page_text: values of electromotive force or potential with the elements of time and polarity
to distinguish the characters of the code from one another.
2. The hereinbefore described improvement in telegraphy which consists in
transmitting for characters of the code successions of elementary signalling
pulses, differing in electromotive force or potential as well as in polarity for
different characters, successive pulsations in each character being of opposite
polarity, thus combining time, polarity, and electromotive force or potential to
distinguish the characters of the code from one another in the manner set forth.
3. In a transmitting apparatus for telegraphy, the combination with an
alternating current generator, of a transmitting tape running in synchronism
therewith and having four rows of perforations, and four transmitting terminals
or brushes adapted to impress upon the circuit four different electromotive forces
or potentials differing in sign and value as described, two being of one sign and
two of an opposite sign.
4. In a transmitting apparatus for code telegraphy, the combination, sub-
stantially as described, of means for generating a continuous and uniform series
of pulses of electromotive force or potential differing in sign and amount, and
a transmitting tape having four rows of perforations and corresponding ter--
minals or brushes adapted to impress successively upon the circuit single pulses
of the said electromotive forces or potentials differing in sign or amount, or
both, as described, to distinguish the characters of a code from one another.
5. In a transmitting apparatus for code telegraphy, the combination of means
for generating or producing continuous series of electromotive forces or potentials
differing in sign and amount, as described, and transmitting or circuit controlling
devices for impressing successively upon the circuit single pulses of the said
series of electromotive forces or potentials differing in sign, or amount, or both,
to distinguish the characters of a code from one another.
:
6. Telegraphic current generating and controlling apparatus constructed,
arranged and operating substantially as herein before described with reference to
and shown respectively in Fig. 1 and in Fig. 2 of the drawings annexed to my
Provisional Specification and the same as modified according to Fig. 3 thereof.
Dated this Sth day of January 1900.
W. LLOYD WISE.
46, Lincoln's Inn Fields, London, W.C.,
Chartered Patent Agent.

page_text: Date of Application, 6th Mar., 1899
Complete Specification Left, 8th Jan., 1900-Accepted, 6th Mar.,
1900
Means for Generating and Impressing Semi-cycles of Electro-motive
Force on Electric Circuits for Telegraphic and other Purposes.
A communication from abroad by ALBERT CUSHING CREHORE, of Hanover, Grafton
County, State of New Hampshire, U.S.A., Professor of Physics, and
LIEUTENANT GEORGE OWEN SQUIER, of Fortress Monroe, Elizabeth City
County, State of Virginia, U.S.A., Lieutenant in U.S.A.
I, WILLIAM LLOYD WISE, of 46, Lincoln's Inn Fields, in the County of
London, Consulting Engineer and Chartered Patent Agent, do hereby declare
the nature of this invention to be as follows:-
The object of this invention is to provide means whereby electro-motive forces
gradually changing in value from zero through a maximum back to zero may be
impressed upon an electric circuit as a series of pulses with any desired time
interval or relation and of any desired polarity successively.
A further object of the invention is to provide a simple and effective means
for developing, in each of two separate circuits, a set of connected semi-cycles
or pulses of electro-motive force, those in each circuit being all of the same sign
and synchronous with but opposite in sign to those in the other.
The invention is especially useful for the transmitting end of a telegraph
employing the code or any other system of transmission, but is not limited to
such use.
The invention consists first, in the combination with alternating current
generating apparatus producing two sets of alternating current electro-motive
forces changing in form or value in the desired manner and of the same perio-
dicity, of circuit making and breaking devices controlling the connection of
said generating apparatus with a circuit and adapted to make and break circuit
at approximately zero instants of current flow so as to impress said electro-motive
forces on the circuit and cause pulses of current in any desired arrangement or
time relation and with immediately succeeding pulses of the same or opposite
polarity as desired.
In carrying out the invention it is preferable to employ a perforated tape as the
means for controlling the times or instants of make and break of circuit, said
tape preferably operating in conjunction with a circuit closing spring or finger
which makes contact through the perforation in the tape and breaks circuit when
riding on the tape, but other forms or construction of devices may be used for
the same purpose.
It is also preferred to employ a dynamo generating apparatus for producing
the electro-motive force since this is a convenient and simple device far superior
to batteries and current reversers, while moreover the natural form of electro-
motive force produced thereby, graphically expressed, is of sine wave form
which has been discovered to be of great value in increasing the practical speed
of code telegraphs, both land and submarine.
The two sets of alternating electro-motive forces which are of the same

page_text: periodicity may be of any relative phase and even of the same phase, but we
prefer to have them differ in phase by one semi-cycle for reasons to be hereinafter
more fully explained.
They may be generated in different portions of the same divided coil or in
different coils operating in the same or different magnetic fields, and wound on
the same or different structures as will be obvious to those skilled in the art of
dynamo construction.
The invention consists further in the combination with an alternating current
dynamo generator developing two sets of electro-motive forces of sine wave type,
preferably differing in phase by a semi-cycle, of commutating or circuit changing
appliances, adapted to change said electro-motive forces into two sets of connected
semi-cycles of the same periodicity, all those in one set being of one polarity
and all those in the other set being of the opposite polarity.
The invention consists further in the novel features and special combinations"
of apparatus hereinafter set forth.
In the accompanying drawings: Fig. 1, represents in skeleton and diagrammati-
cally a form of apparatus embodying the invention as applied to use for a tele-
graph transmitting apparatus. Fig. 2, represents graphically two alternating
electro-motive forces of sine wave type and of the same periodicity but differing
in phase by one semi-cycle as would be the case in the preferred form of the
invention. Fig. 3, shows the same, but with the two waves coinciding in phase.
Fig. 4, shows graphically the electro-motive force conditions in the branches or
circuits leading to the two terminals or electrodes of the circuit controller when
the two waves of electro-motive force shown in Fig. 2. are converted to the form
or conditions employed in this invention when carried out in the preferred
manner. Fig. 5, shows graphically some of the ways in which, by means of the
circuit controller, the electro-motive forces indicated in Fig. 2, may be impressed
upon a circuit as to their time relation or order of succession and as to polarity.
Fig. 6, shows diagrammatically generating coils and circuit changers that might
be used in producing the electro-motive force conditions graphically illustrated
in Figs. 3 and 4. Fig. 7, shows graphically a modification in the electro-motive
force conditions at the two terminals of the circuit controller. Fig. 8, shows
diagrammatically and in skeleton the generating coils, connections and apparatus
that might be used for producing the condition indicated in Fig. 7. Fig. 9;
shows in side elevation a part of the working apparatus embodying the invention
and suited for use in submarine telegraphy. Fig. 10, is an end elevation of the
apparatus. Fig. 11, is a vertical longitudinal section through the parts mechani-
cally connecting the generator and the transmitter or circuit controller. Fig. 12,
is a plan of the transmitting or circuit controlling end of the apparatus. Fig. 13,
shows in side elevation the armature and field of the apparatus as modified for
use on land lines or where very high periodicity is desired. Fig. 14, is a side
elevation and partial vertical section of said modified apparatus. Fig. 15, is a
view of the brush holder in detail. Fig. 16, (Sheet, 4) is a diagram illustrating
the manner of connecting the generator coils to the collector rings and circuit
changer or reverser.
Referring to Fig. 1. 1, 2, indicate two generating coils or sections of gener-
ating coil adapted to produce at the separated or opposite terminals respectively
electro-motive forces of the same periodicity but of opposite sign respectively so
as to differ in phase by a half wave length or one semi-cycle. These electro-
motive force conditions are indicated graphically in Fig. 2. The said coils may
be wound on the same or different structures, operate in the same or different
magnetic fields, and each terminal or coil may alternate in polarity any number
of times in each cycle of operations of the generating apparatus or in each
revolution of the shaft when the said coil is a part of the dynamo machine. They
are here shown as a part of a dynamo generator B, and as adapted to generate.
an alternating electro-motive force of sine wave form or approximately sine wave
form, such as indicated in Fig. 2.

page_text: The coils are shown as wound on a shuttle form of armature which is adapted
to be rotated in a magnetic field which would give one complete wave to each
coil for each whole revolution. While a shuttle form of armature is shown any
other form which will give an electro-motive force more closely following the
sine wave form may be used. The field in which the coils operate is maintained
in any desired way as, for instance, by a local generator M2, supplying a field coil
of the machine. The separate terminals of the two coils of the machine b¹, 2,
connect respectively with the two sides or segments c', c², of a pole changer C,
which operates synchronously with the generated alternating electro-motive
forces in any desired manner as, for instance, by being mounted on the armature
shaft, while the brushes or terminals d', d, for said pole changer connect with the
wires or circuits 1, 2, which terminate respectively in the electrodes, poles or
terminals of any circuit controlling device or circuit making and breaking
appliance by means of which either circuit may be connected for any number of
half wave intervals with the circuit on which the generated pulses of electro-
motive force are to be impressed, and may be disconnected therefrom, the instant
of make and of break, being timed to coincide with the instant the current flow
on said circuit is zero. The opposite terminal of the coils b, b, here shown as
a divided coil or as having a common terminal, joins through a collector
ring and brush H, with the opposite pole of the circuit on which the
pulses of electro-motive force are to be impressed. In the present case and
for purposes of illustration the circuits 1 and 2, are shown as terminating in
the brushes D', D2, for one form of telegraph transmitter in which a perforated
tape is employed and wherein, as well understood in the art, the circuit is closed
through a perforation in the tape and is broken when the contact finger or spring
passes out of the perforation onto the tape. For telegraphic purposes the
terminals 1, 12, could engage through the tape with a contact or contacts con-
nected to earth, as indicated, the opposite terminal of the generator being con-
nected with the line or cable through ring and brush H.
By means of the pole changer the two sets of alternating electro-motive forces
indicated in Fig. 2, are connected into two sets of connected semi-cycles of the
same periodicity on the two circuits or branches 1, 2, respectively, all those in
one set or circuit being of one polarity or sign and all those in the other set
or circuit being of the opposite polarity or sign. This electro-motive force con-
dition of the circuits and their terminals D1, D2, is graphically shown in Fig. 4.
By this means there is continually present at the circuit controller, at each unit
of time or generated half wave of alternating electro-motive force, an electro-
motive force condition of both signs thus furnishing a semi-cycle of either sign
at each instant ready to be impressed on the circuit. Hence said semi-cycles
may be impressed upon the circuit at any instant singly and of either polarity,
or may be impressed as a succession of impulses two or more in number with the
successive pulses all of the same sign or successively alternating in any desired
way throughout the series. Some of the various ways in which this may be done,
are indicated graphically in Fig. 5, which shows the order or relation of pulses
as to the time interval and polarity in the circuit on which they are impressed
The figure shows the order or succession which would be employed in transmitting
some of the characters of the alphabet by the International code, to be recorded
at the receiving end of the line by a siphon recorder or other instrument re-
sponsive to the separate pulses, the unit spaces where no semi-cycle or pulse
appears indicating the suppression of both pulses of generated electro-motive
force at that unit instant of time and corresponding to the space between
characters in the transmitted message.
It is not necessary to use the pole changer whereby semi-cycles of electro-
motive force of one sign only are present at each brush or terminal of the
transmitting tape or other device as said brushes might each be connected
directly with one of the coils 12, through a ring or other continuous connection

page_text: as indicated in Fig. 8, so that the electro-motive force at the two brushes or
terminals would alternate as indicated in Fig. 7. By the former arrangement
if a connected series of semi-cycles of successively opposite sign are to be trans-
mitted they would go to line successively first through one brush or terminal and
then through the other brush or terminal, while in the latter arrangement they
would go through one of the brushes only the other in the meantime riding upon
the paper, the brush selected for the purpose being in any case the one which
would first give an initial semi-cycle of the desired sign.
If the semi-cycles to be transmitted in immediate succession are of the same
polarity, they would in the former case go all by the same brush or terminal,
while in the latter case they would go first by one brush and then by the other.
The former arrangement is, however, preferred in which each brush or terminal
is of a given or the same polarity during every interval of time occupied in the
generation of one semi-cycle and the same brush may, therefore, be used at any
instant to transmit a semi-cycle of the desired or same polarity, whereas in the
latter case it would be sometimes necessary, assuming the same brush or terminal
to be always used for semi-cycles of the same sign in the transmission of a message
to delay one semi-cycle to permit the brush to assume the desired polarity or
else to send the desired combination of semi-cycles by beginning with the opposite
brush which would be obviously objectionable because involving want of uni-
formity in the use of the terminals or the arrangement of perforations for sending
the same character.
By the first named plan the arrangement of perforations is always the same
for the same character while at the same time the utmost possible value is given
to each semi-cycle or unit of time in the transmission of a message.
While it is preferred to organize the generating appliance so that it produces
alternating electro-motive forces displayed in phase by a half wave length, it
may be organized to produce alternating electro-motive forces of the same phase,
with the disadvantage, however, that in order to produce the condition indicated
in Fig. 4 in the two circuits 1, 2, it would be necessary to employ the two pole
changers C, C³, as indicated in Fig. 6, each being provided with two brushes con-
nected respectively to one of the circuits 1ª, 2ª, and to line as shown.
The coils b, b, being connected to the segments of C1, C2, as shown, and the
latter being arranged upon their shaft in phase with one another, an electro-
motive force condition such as indicated in Fig. 4, may be produced at the two
terminals D, Ija.
It will of course be understood that when the circuit is controlled by a per-
forated tape and brushes such as D1, D2, riding thereon, the said tape must be fed
at a speed synchronous with the generation of the alternating electro-motive force
and that the unit of linear space in the tape occupied by perforations should be
the space fed under the brush during the production of one semi-cycle. For
this purpose the tape is provided with a central row of feeding perforations, as
well understood in the art, to be engaged by a toothed wheel F, which runs in
synchronism with the generator B. The length of each perforation being made
to correspond to the number of semi-cycles to be transmitted, the circuit can be
broken at the instant when the current is actually zero for that circuit by
properly adjusting the brush along the tape. This can be done approximately
by adjusting until no spark is visible. The space between perforations being
a unit distance or multiple of unit distance determined as already stated by the
distance of paper fed during the propagation of one semi-cycle of electro-motive
force, the instant of make of circuit will coincide approximately with the natural
zero of current or instant at which it would be zero had it been allowed to flow
uninterruptedly.
Having described the general principles of the invention practical forms of
telegraph transmitting apparatus for submarine cables and for land lines em-
bodying and constituting one application of the invention will now be described.
Referring to Figs. 9 and following, we will first describe a form suited for

page_text: cable use in which the permissible rate of propagation or flow of the distinct
transmitted impulses is comparatively limited.
I, is an armature of a dynamo electric machine wound or provided with two
coils or sections of coil, as already explained, adapted to develope alternating
electro-motive forces of the same periodicity and K, is a field magnet for said
dynamo which field magnet, in an apparatus for submarine cable telegraphs,
might have two poles only so that each coil would develope but one whole wave
of alternating electro-motive force in each revolution.
K, indicates the armature shaft and L', the driving pulley. Upon the armature
shaft and properly insulated therefrom are the four contact rings numbered 1, 2,
3, 4, upon which bear suitable collector brushes supported from a suitable brush
holder H. Ring 4, serves for a connection of the common terminal of the
armature coil system, as shown in Fig. 16, and corresponds to ring H, of the
diagram Fig. 1. Ring 2, is subdivided to furnish the two sides c¹, 2, (Fig. 1,)
of the pole changer upon which bear the two brushes connected to the circuits
leading to the terminals D', D2, or other devices, the halves of said ring consti-
tute in effect parts respectively of the two rings 1, 3, which, in the operation of
the device for the purpose already described, are normally idle, that is to say,
have no collector brushes bearing upon them but have the terminals of the
armature coil system connected directly with them. In the case of a divided coil
like that shown in Fig. 1, it is obvious that by the application of suitable brushes
to the rings 1, 3, an electro-motive force (alternating) which is the sum of that
furnished from the two sections of coils individually may be obtained.
The feed wheel F, for the circuit closing and breaking tape can be driven from
the shaft K, through a suitable intermediate reducing gear comprising pinion H³,
upon the shaft K, arranged to gear with a wheel H', the hub of which carries one
member of the clutch M, the other member of which is carried by the shaft to
which the toothed feed wheel F, is secured. A clutch operating lever M, is
provided and connected with the clutch as clearly shown in Figs. 10, 11 and 12.
The faces of the clutch members which engage are formed with teeth or pro-
jections to interlock as shown, so that the relative position of the feed wheel
and armature coil shall always be the same whenever they are connected together,
thereby causing the circuit controlling devices to be in step or exact phase with
the propagation of the alternating electro-motive forces and insuring a make
and break of circuit at the proper instants, provided that there has been a proper
relative adjustment of the circuit closing fingers to the tape.
The brushes D', D, are carried on a frame or plate T, supported on pins or
studs t, which project from a suitable supporting arm or bracket. The frame T,
is capable of longitudinal adjustment by means of set screws W, carried by it
for the purpose of adjusting the position of the brush tips with relation to the
perforations in the tape and thereby determining the instant at which circuit shall
be broken and made in the alternating current wave produced by the impressed
alternating electro-motive force.
At F, is indicated a pressure wheel which keeps the paper strip engaged by
wheel F. Wheel F1, is supported on a pivoted arm pressed down by a spring as
shown in Fig. 11.
The brushes D1, D2, are carried by a rotatable block or hub of insulation X,
turning on the pin carried by lever P. A spring S, is applied to the hub as
shown, and holds the brushes down upon the perforated tape. By manipulating
lever 1, to raise the hub the brushes may be raised from the paper tape or strip.
The paper feed trough or guide A, is perforated immediately beneath the tips
of the brushes D', 12, to permit them to meet or make contact with other brushes
or contact surfaces beneath the trough, as clearly shown in Fig. 10. Said contact
beneath the trough is supported like contacts or circuit closers D1, D2, by the
frame T.
When the apparatus is to be employed for high speed systems of telegraphy
in which an alternating electro-motive force of higher periodicity is required,

page_text: the construction of the armature and field of the machine may be varied in
obvious fashion to follow the lines of present alternating current dynamo con-
struction as clearly indicated in Figs. 13 and 14, in the former of which is shown
the skeleton of an alternating current dynamo having eighteen armature poles
and adapted to produce nine whole waves of alternating electro-motive force for
cach revolution.
It will be obvious that in the construction of the apparatus previously described
a larger number of alternations might be produced for each revolution of the
armature the speed of the feeding mechanism being changed to the required
degree.
In the case of the apparatus illustrated in Figs. 13 and 14, it is obvious that
the pole changing device would have, if it be secured to the armature shaft as
already explained, a correspondingly increased number of conducting segments
in the ring 2, as clearly indicated in Fig. 14, where each ring 1 and 3, is formed
with segments or projections entering between those of the other and making
in all eighteen segments to correspond to eighteen semi-cycles of electro-motive
force developed in one whole revolution of the armature. The armature may be
wound in the ordinary fashion with its coils connected in continuous series, the
terminals being connected respectively to rings 1 and 3, and the centre of the coil
to ring 4. Feed wheel F, could in this case be made to revolve at the same rate
as the armature shaft K, the two members of the clutch M, being in this case
mounted respectively on the shaft K, and upon the spindle carrying the said
operating wheel of the circuit controlling mechanism. By applying the brushes
to rings 1 and 3, and removing the brushes that bear on rings 2 and 4, it is
obvious that an alternating clectro-motive force of the ordinary type but with
a value equal to the maximum of that developed in the armature is available for
testing or other purposes upon lines or circuits to which the semi-cycles of im-
pressed electro-motive force are to be applied in the manner already described.
In this construction a self-contained machine is available for both purposes.
Dated this 6th day of March 1800
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.
Means for Generating and Impressing Semi-cycles of Electromotive
Force on Electric Circuits for Telegraphic and other Purposes.
A communication from abroad by ALBERT CUSHING CREHORE, of Hanover, Grafton
County, State of New Hampshire, U.S.A., Professor of Physics, and
GEORGE OWEN SQUIER, formerly of Fortress Monroe, Elizabeth City County
State of Virginia, but now of Washington, District of Columbia, U.S.A.,
Captain in the United States Army.
I, WILLIAM LLOYD WISE, of 46, Lincoln's Inn Fields, in the County of
London, Consulting Engineer and Chartered Patent Agent, do hereby declare the
nature of this invention and in what manner the same is to be performed. to be
particularly described and ascertained in and by the following statement:-
This invention relates to means whereby electro-motive forces gradually chang-
ing in value from zero through a maximum back to zero may be impressed upon
an electric circuit as a series of pulses with any desired time intervals or relation
and of any desired polarity successively.
The invention also relates to a simple and effective means for developing, in

page_text: each of two separate circuits, a set of connected semi-cycles or pulses of electro--
motive force, those in each circuit being all of the same sign and synchronous
with but opposite in sign to those in the other.
Such means are especially useful for the transmitting end of a telegraph but
are not limited to such use.
In carrying out the invention there may be used in combination with alter-
nating-current generating-apparatus producing two sets of alternating current
electro-motive forces changing in form or value in the desired manner and of the
same periodicity, circuit making and breaking devices controlling the connexion
of the said generating apparatus with a circuit and adapted to make and break
circuit at approximately zero instants of current flow so as to impress such electro-
motive forces on the circuit and cause pulses of current in any desired arrange-
ment or time relation and with immediately succeeding pulses of the same or
opposite polarity as desired.
It is preferable to employ a perforated tape as the means for controlling the
times or instants of make and break of circuit, the said tape preferably operating
in conjunction with circuit-closing springs or fingers which make contact through
the perforations in the tape and break circuit when riding on the tape, but devices
of other forms or construction may be used for the same purpose.
It is also preferred to employ a dynamo generating apparatus for producing
the electro-motive force since this is a convenient and simple device far superior
to batteries and current reversers, while moreover the natural form of electro-
motive force produced thereby, graphically expressed, is the sine-wave form,
which has been discovered to be of great value in increasing the practical speed
of code telegraphs, both land and submarine.
The two sets of alternating electro-motive forces which are of the same.
periodicity may be of any relative phase and even of the same phase, but it is
preferred to have them differ in phase by one semi-cycle for reasons to be here-
inafter more fully explained. They may be generated in different portions of
the same divided coil or in different coils operating in the same or different
magnetic fields, and wound on the same or different, structures as will be obvious
to those skilled in the art of dynamo construction.
In carrying out the invention there may, however, be used in combination with
an alternating-current dynamo generator developing two sets of electro-motive
forces of sine-wave type, preferably differing in phase by a semi-cycle, commu-
tating or circuit-changing appliances, adapted to change the said electromotive.
forces into two sets of connected semi-cycles of the same periodicity, all those in one
set being of one polarity and all those in the other set being of the opposite.
polarity.
Fig. 1 of the drawings accompanying my Provisional Specification represents.
in skeleton and diagrammatically, telegraphic transmitting-apparatus according.
to this invention. Fig. 2 represents graphically two alternating electromotive
forces of sine-wave type and of the same periodicity but differing in phase by
one semi-cycle, as is preferred. Fig. 3 shows two alternating electromotive forces.
coinciding in phase. Fig. 4 shows graphically the electromotive force conditions
in the branches or circuits leading to the two terminals or electrodes of the
circuit controller when the two electromotive forces shown in Fig. 2 are converted
into the preferred form. Fig. 5 shows graphically some of the ways in which,
by means of the circuit controller electromotive forces indicated in Fig. 4 may be
impressed upon a circuit so as to indicate letters according to code, by their
succession, polarity, and the intervals between them. Fig. 6 shows, diagram-
matically, generating coils and circuit changers that might be used in producing.
the electromotive force conditions graphically illustrated in Figs. 3 and 4. Fig. 7.
shows graphically a modification in the electromotive force conditions at the two
terminals of the circuit controller. Fig. 8 shows diagrammatically and in-
skeleton the generating coils, connexions, and apparatus that might be used for
producing the condition indicated in Fig. 7. Fig. 9 shows in side elevation a

page_text: part of apparatus according to this invention and suited for use in submarine
telegraphy Fig. 10 is an end elevation thereof: Fig. 11 is a vertical longitudinal
section of the parts mechanically connecting the generator and the transmitter
or circuit controller; Fig. 12 is a plan of the transmitting or circuit controlling
end of the apparatus: Fig. 13 shows in side elevation the armature and field of
the apparatus as modified for use on land lines or where very high periodicity
is desired; Fig. 14 is a side elevation and partial vertical section of the apparatus"
so modified; Fig. 15 is a view of the brush holder in detail; and Fig. 16 (Sheet 4)
is a diagram illustrating the manner of connecting the generator coils to the
collector rings and circuit changer or reverser.
In Fig. 1, and 62 indicate two generating coils or sections of generating
coil adapted to produce at the separated or opposite terminals respectively
electromotive forces of the same periodicity but of opposite signs-i.e., electro-
motive forces that differ in phase by a half wave length or one semi-cvcle.
These electromotive force conditions are indicated graphically in Fig. 2. Such
coils may be wound on the same or different structures, and operate in the same
or different magnetic fields, and each terminal or coil may alternate in polarity
any number of times in each cycle of operations of the generating apparatus or
in each revolution of the shaft when the coil or coils is or are a part of the
dynamo machine. They are here shown as a part of a dynamo generator B and
as adapted to generate alternately electromotive force of sine-wave form or ap-
proximately sine-wave form. such as indicated in Fig. 2. The coils are shown
as wound on an armature of shuttle-form, which is adapted to be rotated in a
magnetic field which would give one complete wave to each coil for each whole
revolution. While an armature of shuttle form is shown, it is preferred to use
one of such a form that it will give an electromotive force more closely following
the sine-wave form-for example, a drum-wound armature with a two-segment
commutator and a single collector ring connected to the centre of the winding.
The field in which the coils operate may be maintained in any desired way, as,
for instance, by a local generator M2 supplying a field coil of the machine. The
separate terminals of the two coils of the machine 61, 62, are connected respectively
with the two sides or segments c¹², of a pole changer C, which may be operated
synchronously with the production of the alternating electromotive force in any
desired manner-for instance, the pole-changer C may be mounted on the armature
shaft while the brushes or terminals and 2 for the said pole changer may be
connected with the wires 1 and 2ª which terminate respectively in the electrodes,
poles, or terminals of any circuit-controlling device or circuit making and break-
ing appliance by means of which either circuit may be connected for any number
of half wave intervals with the circuit on which the generated pulses of electro-
motive force are to be impressed, and may be disconnected therefrom, the instants
of make and of break being timed to coincide with the instants at which the current
flow on the said circuit is zero. The opposite terminal of each of the coils 17°
(here shown as a divided coil or as having a common terminal) communicates,
through a collector ring and brush H, with the opposite pole of the circuit on
which the pulses of electromotive force are to be impressed. In the present case
and for purposes of illustration, the wires 1 and 2ª are shown as terminating in
the brushes D1, D2 of a telegraphic transmitter in which a perforated tape is
emploved, and wherein, as well understood in the art, the circuit is closed through
a perforation in the tape and is broken when the contact finger or spring passes
out of the perforation and upon the tape. For telegraphic purposes the termi-
nals D, D² could engage through the tape with a contact or contacts connected
to earth, as indicated, the opposite terminal of the generator being connected
with the line through the ring and brush H.
By means of the pole-changer. the two sets of alternating electromotive forces
indicated in Fig. 2 are converted into two sets of connected semi-cycles of the
same periodicity on the two branches 1 and 2ª respectively, all those in one
set or circuit being of one polarity or sign and all those in the other set or

page_text: circuit being of the opposite polarity or sign. This electromotive force condition
of the circuits and their terminals D1, D2 is graphically shown in Fig. 4. By
this means there are caused to be continually present at the circuit controller, at
each unit of time or generated half wave of alternating .electromotive force,
electromotive forces of opposite signs, so that there is a semi-cycle of each sign
at each instant ready to be impressed on the line. Hence such semi-
cycles may be impressed upon the line at any instant singly and of
either. polarity, or may be impressed as a succession of impulses two or more in
number with the successive pulses all of the same sign or alternating or otherwise
changing in any desired way throughout the series. Some of the various ways
in which this may be done are indicated graphically in Fig. 5, which shows the
order or relation of pulses as to the time intervals and the polarity in the circuit
or line on which they are impressed. The figure shows the order or succession
which would be employed in transmitting some of the characters of the alphabet
by the international code, to be recorded at the receiving end of the line by a
siphon recorder or other instrument responsive to the separate pulses, the unit
spaces where no semi-cycle or pulse appears indicating the suppression of both
pulses of generated electromotive force during that unit instant of time and corre-
sponding to the space between characters in the transmitted message.
It is not necessary to use the pole-changer whereby semi-cycles of electro-
motive force of one sign only are caused to be present at each brush or terminal
of the transmitting tape or other equivalent device, as the said brushes might each
be connected directly with one of the coils and 2 through a ring or other con-
tinuous connexion as indicated in Fig. 8, so that the electromotive force at the
two, brushes or terminals would alternate as indicated in Fig. 7. With the former
arrangement, if a connected series of semi-cycles of successively opposite sign
are to be transmitted, they would go to line successively first through one brush
or, terminal and then through the other brush or terminal, while in the latter
arrangement they would go through one of the brushes only, the other in the
meantime riding upon the paper and the brush selected for the purpose being
in any case the one which would first give an initial semi-cycle of the desired
sign.
If the semi-cycles to be transmitted in immediate succession are of the same
polarity, they would in the former case go all by the same brush or terminal,
while in the latter case they would go first by one brush and then by the other.
The former arrangement is, however, preferred, in which each brush or terminal
is of a given or the same polarity during every interval of time occupied in the
generation of one semi-cycle, and the same brush may, therefore, be used at any
instant to transmit a semi-cycle of the desired or same polarity, whereas in the
latter case it would be sometimes necessary, if the same brush or terminal had to be
always used for initial semi-cycles of the same sign in the transmission of a
message, to delay one semi-cycle to permit the brush to assume the desired
polarity or else it would be necessary to send the desired combination of semi-
cycles by beginning with the opposite brush, which would be obviously objection-
able because involving want of uniformity in the use of the terminals or the
arrangement of perforations for sending the same character.
With the first named plan the arrangement of perforations is always the same
for the same character, while at the same time the utmost possible value is given
to each semi-cycle or unit of time in the transmission of a message.
+
While it is preferred to construct the generating appliance so that it will pro-
duce alternating electro-motive forces displaced in phase by a half wave length,
it may be constructed to produce alternating electromotive forces of the same
phase, with the disadvantage, however, that in order to produce the condition
indicated in Fig. 4. in the two leads 1 and 2, it would be necessary to employ
two pole-changers C1 and C2, as indicated in Fig. 6, each being provided with two
brushes connected respectively to one of the leads' 1 and 2. and to line as shown.
The coils 1, 2 being connected to the segments of C and C2 as shown, and the

page_text: segments C and C³ being arranged upon their shaft in phase with one another,
an electromotive force condition such as indicated in Fig. 4 will be produced at
the two terminals D1 and D2.
It will, of course, be understood that when the circuit is controlled by a per-
forated tape and brushes, such as 1 and D2, riding thereon, the said tape must
be fed at a speed synchronous with the generation of alternating electromotive
force and that the unit of linear space in the tape occupied by perforations should
be the space fed under the brush during the production of one semi-cycle. For
this purpose the tape is provided with a central row of feeding perforations, as
well understood in the art, to be engaged by a toothed wheel F (Fig. 1), which
runs in synchronism with the generator B. The length of each perforation being
made to correspond to the number of semi-cycles to be transmitted, the circuit
can be broken at the instant when the current is actually zero for that circuit
by properly adjusting the brush along the tape. This can be done approximately
by adjusting until no spark is visible. The space between perforations being a
unit distance or multiple of unit distance determined as already stated by the
distance of paper fed during the propagation of one semi-cycle of electromotive
force, the instant of make of circuit will coincide approximately with the natural
zero of current or instant at which it would be zero had it been allowed to flow
uninterruptedly.
The general principles on which the invention is based having been described.
telegraphic transmitting apparatus according thereto suitable for submarine
cables and for land lines will now be described.
Referring to Figs. 9 to 12 inclusive, I will first describe apparatus suited for
cable use in which the permissible rate of propagation or flow of the distinct
transmitted impulses is comparatively limited.
I represents an armature of a dynamo-electric machine wound or provided, ag
already explained, with two coils or sections of coil adapted to develop alternating
electromotive forces of the same periodicity; and R represents a field magnet for
the said dynamo, which field magnet, in an apparatus for submarine cable tele-
graphs, might have two poles only so that each coil would develop only one whole
wave of alternating electromotive force in each revolution. K indicates the arma-
ture shaft, and L' the driving pulley. Upon the armature shaft and properly in-
sulated therefrom are four contact rings numbered 1, 2, 3, 4, upon which bear
suitable collector brushes supported from a suitable brush holder H. The ring 4
serves as a connexion for the common terminal of the armature coil system as shown
in Fig. 16, and corresponds to the ring H of the diagram Fig. 1. The ring 2 is
subdivided to furnish the two sides, (Fig. 1) of the pole changer upon
which bear the two brushes connected to the terminals D1, D2 or other equivalent
devices; the halves of the ring 2 constitute in effect parts respectively of the two
rings 1 and 3, which, in the operation of the apparatus for the purpose already
described, are normally idle-this is to say, have no collector brushes bearing upon
them but have the terminals of the armature coil system connected directly to
them. In the case of a divided coil like that shown in Fig. 1, it is obvious that
by the application of suitable brushes to the rings 1 and 3 and removing the
brushes from the rings 2 and 4. an electromotive force (alternating) which is the
sum of that furnished from the two sections of coils individually, may be obtained.
The feed wheel F for the circuit closing and breaking tape can be driven from
the shaft through a suitable intermediate reducing gear comprising a pinion H
fixed on the shaft K and connected by an intermediate wheel with a wheel H
the hub of which carries one member of a clutch M, the other member of which
is carried by the shaft to which the toothed feed wheel F is secured. A clutch-
operating lever M is provided and connected with the clutch as clearly shown
in Figs. 10. 11. and 12. The faces of the clutch members which engage with
each other are formed with teeth or projections to interlock as shown. so that
whenever the feed wheel and the armature coil will be connected together their

page_text: relative position will always be the same--that is to say, the circuit-controlling
device will be in step or exact phase with the propagation of the alternating
electromotive forces, and making and breaking of circuit at the proper instants
will be insured provided that there has been a proper relative adjustment of the
circuit-closing fingers to the tape.
The brushes D and I are carried on a frame or plate T supported on pins or
studs t, which project from a suitable supporting arm or bracket. The frame or
plate T is capable of longitudinal adjustment by means of set-screws W carried
by it for the purpose of adjusting the position of the brush tips with relation
to the perforations in the tape and thereby determining the instant at which cir-
cuit shall be broken and made in the alternating current wave produced by the
impressed alternating electromotive force.
At F is indicated a pressure wheel which keeps the paper strip engaged by the
wheel F. The wheel F is supported on a pivoted arm pressed down by a spring
as shown in Fig. 11.
The brushes D¹ and 12 are carried by a rotatable block or hub R of insulation
turning on a pin carried by an elbow lever P pivoted at .. A spring S is applied
to the hub as shown, and holds the brushes down upon the perforated tape. By
manipulating the lever P to raise the hub, the brushes may be raised from the
paper tape or strip. The paper feed trough or guide A2 is perforated immediately
beneath the tips of the brushes D1 and D2 to permit them to meet or make con-
tact with other brushes or contact surfaces beneath the trough, as clearly shown
in Fig. 10. The contact brushes or surfaces beneath the trough are supported,
like the contacts or circuit closers D' and D2, by the frame T.
When the apparatus is to be employed for high-speed systems of telegraphy
in which an alternating electromotive force of higher periodicity is required, the
construction of the armature and the field of the machine may be varied in
obvious fashion to follow the lines of present alternating-current dynamo con-
struction as clearly indicated in Figs. 13 and 14, in the former of which is shown
the skeleton of an alternating-current dynamo having eighteen armature poles
and adapted to produce nine whole waves of alternating electromotive force for
each revolution.
It will be obvious that in the construction of the apparatus previously described,
a larger number of alternations might be produced for each revolution of the
armature, the speed of the feeding mechanism being changed to the required
degree.
In the case of the apparatus illustrated in Figs. 13 and 14, it is obvious that
the pole changing device will, if it be secured to the armature shaft as already
explained, have a correspondingly increased number of conducting segments in
the ring 2, as clearly indicated in Fig. 14, where each ring 1 and 3 is shown as
formed with segments or projections entering between those of the other and
making in all eighteen segments to correspond to eighteen semi-cycles of electro-
motive force developed in one whole revolution of the armature. The armature
may be wound in the ordinary fashion with its coils connected in continuous
series, the terminals being connected respectively to the rings 1 and 3. and the
centre of the coil being connected to the ring 4. The feed wheel F could in this
case be made to revolve at the same rate as the armature shaft K, the two members
of the clutch M being in this case mounted respectively on the shaft K and on
the spindle carrying the wheel F of the circuit-controlling mechanism. By apply-
ing brushes to the rings 1 and 3. and removing the brushes from the rings 2 and
4, it is obvious that an alternating electromotive force of the ordinary type but
with a value equal to the maximum of that developed in the armature can be
obtained and used for testing or other purposes upon lines or circuits to which
the semi-cycles of impressed electromotive force are to be applied in the manner
already described. In this construction a self-contained machine is available for
both purposes.

page_text: Having now particularly described and ascertained the nature of the said in-
vention and in what manner the same is to be performed, I would have it under-
stood that I do not, of course, wish to claim anything claimed in my Patent
Specification No. 23556 of 1898, but I declare that what I claim is:-
1. The combination (except as part of a submarine cable telegraph) with an
alternating generator producing two alternating electromotive forces of the same
periodicity, of circuit interrupting devices adapted to make and break circuit at
instants when the current flow is actually or approximately zero and to impress
the said electromotive forces on the circuit so as to cause semi-cycles of current
to flow in the desired order or relation and those in immediate succèssion 'to 'be
of the same sign or of opposite signs as desired.
i.
2. The combination (except as part of a submarine cable telegraph) witli a
dynamo generating apparatus producing two alternating electromotive forces, of
sine wave type and of the same periodicity, of means for delivering the, said
electromotive forces at the transmitter terminals as two sets of semi-cycles of
electromotive force of continuously the same sign at the said interminals re-
spectively, and means for impressing the same upon the circuit for causing .com-
plete semi-cycles of current of either sign to be transmitted beginning and ending
at zero or approximately zero and in any desired order or succession.
3. The combination (except as part of a submarine cable telegraph) with an
alternating-current two-phase generator developing alternating electromotive
forces of the sine wave type and of the same periodicity of circuit making and
breaking devices adapted to make and break circuit at instants of natural zero
or approximately natural zero in the current flow, and to impress the said electro-
motive forces upon the circuit in any desired order or relation either singly or
as a connected series of pulses in which successive pulses are of the same or
alternate polarity as required.
4. The combination (except as part of a submarine cable telegraph) with an
alternating current generator producing two electromotive forces of sine wave
type and of the same periodicity, of means for converting the said electromotive
forces into two sets of connected semi-cycles on two separate circuits, all of the
semi-cycles in each being of the same polarity.
5. The combination (except as part of a submarine cable telegraph) with an
alternating-current generator developing two alternating electromotive forces
differing in phase by one semi-cycle, of a pole changer for changing the said
electromotive forces into two series of connected semi-cycles of the same periodi-
city, all the semi-cycles in one set being of one polarity and all those in the other
set being of the opposite polarity.
6. The combination (except as part of a submarine cable telegraph) with a
two phase generator of alternating electromotive force producing electromotive
forces of sine-wave type differing in phase by one semi-cycle, of means for deliver-
ing the said electromotive forces at the transmitter terminals as two sets of
semi-cycles of electromotive force of continuously the same sign at the said
terminals respectively, and means for impressing the same upon the circuit so
as to cause complete semi-cycles of current beginning and ending at zero or ap-
proximately zero to flow along the circuit in any desired order or succession as
to polarity.
7. The combination with an alternating-current generator and circuit-controll-
ing devices operating in synchronism therewith, as described, of a clutch for dis-
connecting the dynamo shaft from the shaft of the said circuit controlling devices
and formed as described so as to cause them to be kept in step or phase on being
again connected, substantially as set forth.
8. The combination with a dynamo developing two electromotive forces
differing in phase by a one half wave length, of three continuous collector rings
one of which is connected to a common terminal of the generating coils while
the other two are connected respectively to the opposite terminals of the said
coils and themselves terminate in the opposite segments of a pole changer,

page_text: whereby as described the machine may be made to deliver two electromotive forces
differing in phase or a single electromotive force whose value is the sum of the
two which differ in phase, substantially as set forth.
9. The combination,. substantially as described, (except in a submarine cable
telegraph) of a two-phase alternating current generator developing electro-
motive forces differing in phase by one semi-cycle or half wave length, a syn-
chronously operating transmitter, and a pole changer between the generator and
transmitter for changing the two alternating waves of developed electromotive
force into two connected series of semi-cycles of electromotive force of opposite
polarity at the two terminals of the transmitter.
10. Current generating and controlling apparatus constructed, arranged, and
operating substantially as hereinbefore described with reference to and shown in
Figs. 1, 2, and 4 (except in a submarine cable telegraph), in Figs. 3, 4, and 6, in
Figs. 7 and 8, in Figs. 9 to 12 inclusive and Fig. 16, or Figs. 13, 14, and 15, of
the drawings filed with my Provisional Specification.
Dated this 8th day of January 1900.
W. LLOYD WISE.
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.