IMPROVEMENTS IN AND CONNECTED WITH TELEGRAPH APPARATUS
Year: 1880

page_text: LETTERS PATENT to Carl Kesseler, of 63, Mohrenstrasse, Berlin, W., in the
Empire of Germany, Civil Engineer and Patent Solicitor, for an Invention
of "IMPROVEMENTS IN AND CONNECTED WITH TELEGRAPH APPARATUS."
A communication from Friedrich Fuchs, of Berlin, in the German Empire.
PROVISIONAL SPECIFICATION left by the said Carl Kesseler at the Office
of the Commissioners of Patents on the 2nd July 1880.
CARL KESSELER, of 63, Mohrenstrasse, Berlin, W., in the Empire of Germany,
Civil Engineer and Patent Solicitor. "IMPROVEMENTS IN AND CONNECTED WITII
TELEGRAPII APPARATUS." (A communication from Friedrich Fuchs, of Berlin, in
the German Empire.)
For telegraphing by the Morse apparatus in the manner shown in the annexed
Diagrams no special auxiliary apparatus are needed. But the Morse key requires
the application of another or contact lever, which according to whether the circuit
connections shown in Diagrams I. or II, is to be used requires to be arranged
accordingly.
The contact lever for the circuit connection in Diagram II. consists of the lever
proper, its fulcrum spindle at one end, an adjustable contact screw, a helical spring
intermediate between the two, the bracket for supporting the fulcrum spindle
Under the outer end of the
between centres and containing a binding screw.
contact lever there is an angular earth contact plate carrying a contact pillar and a
binding screw. The supporting bracket is fastened to the wooden bed plate of the
Morse key by two wood screws, and the earth contact plate by one wood screw;
the latter is also kept in place by steady pin formed by a cylindrical continuation
of the lower screwed end of the contact pillar which is tapped into the earth
contact plate.
The earth contact plate of the Morse key is shortened at both ends, leaving only
the middle part standing with the anvil on, which limits the downward movement
of the key lever.

page_text: The contact lever for the second mode of circuit connecting, sec Diagram II.,
consists of an upper bar and a lower bar, each united by two screws to an
intermediate block, forming thus a fork, in which the back end of the key lever
enters. The upper bar is insulated from the block it is fitted with an adjustable
contact screw. The block has a hole for a conical fulcrum pin which has its
bearings in a bracket or carriage fastened to the bed plate, and fitted with a
binding screw. To the upper bar of the contact levor the battery is to be connected;
for this purpose there is a brass plate let into the bottom of the bed plate, and
provided with a binding screw. The metallic connection between the brass plate
and the upper bar of the contact lever is made by a helical spring, which also has
the office to bring the said lever after each lift by the key lever back into the
position of rest. The helical spring is insulated from the lower half of the contact
lever; it is fastened to the brass plate by a binding screw, and to the upper half of
the contact lever by a set screw. When the key is in the position of rest the upper
part of the contact lever rests on the anvil of the earth contact plate of the Morse
key; this latter plate is shortened to give more room for contact lever on the
bed plate of the key. The key lever has an ivory peg below and runs off taper to
the back. If the contact lever in the first-case is to be applied, this taper must be
on the top; but for the application of the contact lever in the second case the taper
must be below.
Each of the contact levers described is applicable to a Morse key of any form.
The circuit connections can be made in three ways, viz., with the ordinary Morse
key without altering the same, or with the key combined with the contact lever
first described, or with the contact lever last described.
These three modes are illustrated in the Diagrams I., U., and III.
In Diagram I. the vibration of the key acts disturbingly, for which reason the
above alterations in the key are necessary.
The arrangements II. and III. are alike reliable. As the first however is
preferable because of greater simplicity, it should be reckoned the normal one.
The mode in which telegraphing is carried on is as follows:-If the key at
station A is depressed, the contact screw on the contact lever B being set properly,
the connection between the latter and the earth contact plate interrupted at the
pillar, and the electro magnet coils of the apparatus separated from each other, that
is, the coil R thrown ont of circuit. But in the moment the koy lever A touches
the contact screw the battery is closed, and the current therefrom passes by b
through the coil R¹ into the line wire. At the station B where there is still contact
at a the current traverses the two coils of the apparatus and then goes to the earth.
When the return spring of the armature is properly regulated, the apparatus at A,
where the current only passes through one coil, does not speak, whereas the
apparatus at B, where the magnetic influence on the armature is about double that
of A, gives off writing.
If the key at A and that at B are simultaneously depressed, the coil R' is thrown
out at both stations; but as now also the batteries of both stations which are
placed against earth with their opposite poles send their current into the line wire,
and as moreover the coil R¹ is traversed by a current of double the strength than
when speaking, and hence the magnetic influence on the armature is as great
as when the current from one battery traversed both coils, it follows that the
apparatus must write both at A and B. As soon as now the key on one station
drops into its normal state of rest, the current in the line wire falls to half its
strength, and the armature of the apparatus on the other station falls off.
This telegraphing is conditional on the approximate assimilation of the batteries.
The resistance of one battery must also be made as like that of the coil R² as
possible. This latter is not of much consequence on long distances, but on short
distances current variations become apparent if this condition is not fulfilled. They
may however be easily obviated by including a constant artificial resistance in the
battery branch. Experience has further shewn that this circuit connection will not

page_text: work in line wires whose loading capacity exceeds 8 microfarads, corresponding to
and over ground line of about 400 kilometre, or say 250 miles. If it is required
to telegraph at greater distances, the number of windings in the coil 2 must be
increased, or the electro magnet ores must be parted from each other by cutting
through the connecting piece, or, what appears the best, a connection must be put in
the circuit, as shewn in Diagram IV. For this purpose the telegraph apparatus
must be provided with a fork shaped contact lever, acting on the same principle as
the contact lever of the key. The writing lever which here takes the place of the
key lever of the Morse key has on its upper surface, where it in the position of
rest touches the contact lever, a small ivory peg. The action of this appliance
explains itself from the above explanations of the current circuit.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
-
by the said Carl Kesseler in the Great Seal Patent Office on the 1st January
1881.
CARL KESSELER, of 63, Mohrenstrasse, Berlin, W., in the. Empire of Germany,
Civil Engineer and Patent Solicitor. "IMPROVEMENTS IN AND CONNECTED WITH
TELEGRAPH APPARATUS." (A communication from Friedrich Fuchs, of Berlin, in
the German Empire.)
For telegraphing by the Morse apparatus in the manner shown in the annexed
Diagrams no special auxiliary apparatus are needed. But the Morse key requires
the application of another or contact lever, which according to whether the circuit
connections shown in Diagrams I. or 11. is to be used, requires to be arranged either
in the form shown in Figure 2 or in Figure 6.
The contact lever B, Figures 1 and 2, for the circuit connection in Diagram II.
consists of the lever proper a, its fulcrum spindle b at one end, an adjustable contact
screw c, a helical spring & intermediate between the two, the bracket c for supporting
the fulcrum spindle b between centres g, g', and containing a binding screw f; under
the outer end of the contact lever there is an angular carth contact plate / carrying
a contact pillar i and a binding screw k. The supporting bracket e is fastened to
the wooden bed plate of the Morse key by two wood screws, and the earth contact
plate by one wood screw; the latter is also kept in place by steady pin formed
by a cylindrical continuation of the lower screwed end of the contact pillar i which
is tapped into the earth contact plate h.
The earth contact plate of the Morse key is, as shown in Figure 1, shortened at
both cuds, leaving only the middle part standing with the auvil on, which limits
the downward movement of the key lever A.
The contact lever B, Figures-3; 4; 5;-and-6, for the second. mode of circuit.
connecting, Ece Diagram 11., consists of an upper bar or member m, and a lower
bar m, each united by two screws respectively n, n¹, and n¹ and 11, to an
intermediate block o, forming thus a fork in which the back end of the key lover A
enters. The upper bar or member m is insulated from the block o by an ebonito
plate p, and by ebonite ferrules q and q¹ for the screws n, n, to pass through; it is
fitted with an adjustable contact screw r. The block o has a hole for a conical
fulcrum pin 8, which has its bearings in a bracket or carriaget fastened to the bed
plate, and fitted with a binding screw u. To the upper bar m of the contact
lever B¹ the battery is to be connected; for this purpose there is a brass plate v let
into the bottom of the bed plate and provided with a binding screw w. The
metallic connection between the brass plate v and the upper bar m of the contact
lever B' is made by a helical spring a, which also has the office to bring the said
lever after each lift by the key lever A back into the position of rest. The holical
spring is insulated from the lower half m' of the contact lever B by an ebonite
ferrule; it is fastened to the brass plate vby a binding screw, and to the upper
half m of the contact lever B by a set screw, as shown in Figures 4 and 6. When
the key is in the position of rest the upper part m' of the contact lever B¹ rests on
the anvil a of the earth contact plate a', Figure 6, of the Morse key; this latter
plate is, as shown in Figure 6, shortened to give more room for the contact lover on
the bed plate of the key. The key lever has an ivory peg below and runs off taper
to the back. If the contact lever Figure 2 in the first case is to be applied, this
taper must be on the top; but for the application of the contact lever, Figure 6, in
the second case, the taper must be below; compare with Figure 3. The pattern of
Morse key shown is the one used in Germany.
Each of the contact levers described is applicable to a Morse key of any form.
The circuit connections can be made in three ways, viz., with the ordinary Morse
key without altering the same, or with the key combined with the contact lever

page_text: first described with reference to Figures 1 and 2, or with the contact lever last
described with reference to Figures 3, 4, 5, and 6.
These three modes are illustrated in the Diagrams I., II., and III.
In Diagram I. the vibration of the key acts disturbingly, for which reason the
above alterations in the key are necessary.
The arrangements II, and III. are alike reliable. As the first however is
preferable because of greater simplicity, it should be reckoned the normal one.
The two other circuit connections are only put in to prevent others from laying
claim to them.
The mode in which telegraphing is carried on is as follows:-If the key at
station A is depressed, the contact screw on the contact lever B being set properly,
the connection between the latter and the earth contact plate is interrupted at
the pillar a, and the electro-magnet coils of the apparatus separated from each
other, that is, the coil R2 thrown out of circuit.
But in the moment the key lever A touches the contact screw c, Figure 2,
or r, Figure 6, the battery is closed, and the current therefrom passes by b through
the coil R' into the line wire. At the station B where there is still contact at a
the current traverses the two coils of the apparatus, and then goes to earth.
When the return spring of the armature is properly regulated, the apparatus at A,
whore the current only passes through one coil, does not speak, whereas the
apparatus at B, where the magnetic influence on the armature is about doublo
that of A, gives off writing.
If the key at A. and that at B are simultaneously depressed, the coil R² is thrown
out at both stations; but as now also the batteries of both stations which are
placed against earth with their opposite poles send their current into the line
wire, and as moreover the coil R¹ is traversed by a current of double the strength
than when speaking, and hence, the magnetic influence on the armature is as
great as when the current from one battery traversed both coils, it follows that
the
apparatus must write both at A and B. As soon as now the key on one station
drops into its normal state of rest, the current in the line wire falls to half its
strength, and the armature of the apparatus on the other station falls off.
This telegraphing is conditional on the approximate assimilation of the batteries.
The resistance of one battery must also be made as like that of the coil R as
possible. This latter is not of much consequence on long distances, but on short
distances current variations become apparent if this condition is not fulfilled.
They may however be easily obviated by including a constant artificial resistance
in the battery branch. Experience has further shown that this circuit connection
will not work in line wires whose loading capacity exceeds 8 microfarads, corre-
sponding to an overground line of about 400 kilometer, or say 250 miles. If it
is required to telegraph at greater distances, the number of windings in the coil 2
must be increased, or the electro-magnet cores must be parted from each other
by cutting through the connecting piece, or, what appears the best, a transfer must
be put in the circuit, such a one is shown in Diagram IV. For the purpose of
this transfer the telegraph apparatus must be provided with a fork shaped contact
lever, acting on the same principle as the contact lever of the key. The writing
lever, which here takes the place of the key lever of the Morse key, has on its
upper surface where it in the position of rest touches the contact lever a small
ivory peg. The action of this transfer appliance explains itself from the above
explanations of the current circuit. By the arrangement here shown the bed
plate or board of the ordinary Morse key can contain also the extra lever B;
hence it is only necessary to screw a new part to the bed plate, to shorten the
earth contact plate or to modify its form, and to alter the end of the koy lever A
in height according to the requirements of the new combination.
And having thus described and ascertained the nature of this Invention
communicated to me, I declare that I claim,-
First. An appliance for telegraphing by means of the Morse apparatus, consisting

page_text: in a combination of a Morse key of any construction with a contact lever B, as
shown in Figures 1 and 2, the plane of vibration of which crosses that of the
-lever A, the contact lever being arranged on the bed plate of the Morse key, and so
that the acting point or end of the lever A is between the fulcrum and the outer
point or end of the contact lever.
Second. The combination of the lever B with the anvil i and the lever A, for the
purpose of decreasing the short circuit of the battery.
Third. The combination of the lever of a Morse key with a fork shaped contact
lever B', as shown in Figures 3, 4, 5, and 6, consisting of the bars or members m, m³,
with connecting piece o, and insulator p, also so arranged on the bed plate of the
usual Morse key that the planes of vibration of both main parts of this combination
cross each other.
Fourth. The arrangement of the spring which passes insulated and freely
through the lower member m³ of the contact lever B₁, and is fixed to the upper
member m by a set screw, and is in current connection with it.
Fifth. The arrangement of the circuits I., II., and IV., in combination with the
Morse key combined as before described, or with a telegraph for telegraphic
communication, and based on this-that the current does not pass direct from one
coil of the electro-magnet to the other, but first by the key, and so that in the
transmitting instrument only one coil remains in circuit, whilst in the receiver both
coils are in circuit, and in conversing when in each apparatus a coil is put into
circuit both batteries send their current through the wire, and hence the separate
electro-magnet legs act powerfully enough to attract the armature, the essential
point being the separation of the two coils of the electro-magnet in order to keep
them out of action in the-transmitter; but double in the receiver with one battery,
or by conversing to let them work singly with both batteries.
In witness whereof, I, the said Carl Kesseler, have hereunto set my hand and
seal, this Twenty-seventh day of December, in the year of our Lord One
-thousand-eight hundred and eighty.
-
CARL KESSELER¯¯¯¯¯i.q^\'—'