Appliances for Facilitating the Training and Firing of Guns.
Year: 1890

page_text: Date of Application, 28th Nov., 1890
Complete Specification Left, 18th Aug., 1891-Accepted, 17th Oct., 1891
[Communicated from abroad by Messrs. SIEMENS & HALSKE, of Berlin, in the
German Empire, Electrical Engineers.]
Appliances for Facilitating the Training and Firing of Guns.
We, SIEMENS BROTHERS & Co. LIMITED of 12 Queen Anne's Gate,
Westminster in the County of Middlesex, Electrical Engineers, do hereby
declare the nature of this invention to be as follows:-
This invention relates to the application to guns of electrical and other
appliances for effecting the training or bringing into firing position thereof, as also
for effecting the firing of the gun by the officer in charge situated in a central
position at a distance from the gun, or by others executing his commands, the
arrangement being such that the firing cannot be effected until the gun has been
brought into the exact position required.
In most cases the officer in charge will employ a separate sighting instrument or
range-finder and will effect the adjustment of the gun according to the indications
obtained by this, but this instrument might also be combined with the actuating
mechanism, so that the adjustment of the gun will always depend upon the adjust-
ment of the sighting instrument and the officer in charge will only have to adjust
the latter and give the command to fire, or, with electric firing, effect this himself,
such firing being however prevented as long as the position of the gun does not
correspond to that of the sighting device.
The dependence of the firing upon the correct adjustment of the gun can be
insured by causing an electric circuit which serves either to convey the command,
or for effecting the electric firing, or the electric release of a mechanical firing
device, to be interrupted as long as the direction of the gun does not coincide with
that of the sighting device, and only to be closed when such coincidence takes
place.
By means of the apparatus which forms the subject of the present invention, the
training or adjustment of the gun can be effected both laterally and vertically, as
also simultaneously in both directions combined, and the firing can be made to
depend upon the correct adjustment in each of the two directions.
In order to facilitate the description of the various modes of carrying out this
invention we will first describe the simplest case, namely that in which the hori-
zontal adjustment of the gun is effected by the gunners according to indications of
a command apparatus.
Referring to Figure 1 of the accompanying drawings, the receiver E of the
command apparatus, which may be of any of the known electric, mechanical,
pneumatic &c. constructions, is attached to the pivot pedestal P of the gun so that
its pointer Z can turn round the vertical axis of the gun, and points directly to the
position into which the gun is to be brought. The gun R carries a contact spring j
which makes a conducting contact with the pointer Z as soon as both parts lie in
exactly the same direction, thereby closing a firing circuit enabling the gun to be
fired. The receiver of the command apparatus might also be combined with the
gun itself, so that the pointer thereof can rotate upon the vertical pivot axis of
the gun, but the whole receiving apparatus, with its pointer follows the movements
of the gun, and in this case the position of the pointer relatively to a fixed directing
line, or the relative distance of a part of the pointer from an externally situated
fixed point, may serve to indicate the required adjustment of the gun. The latter
would in this case have to be turned in such a manner that the pointer is made to
coincide with the fixed point in order to enable the firing to be effected.
The command apparatus may consist of a galvanoscope with three positions,
namely a middle position for the correct adjustment of the gun, and two side

page_text: positions, for indicating the direction in which the gun is to be moved. This
galvanoscope, can be variously constructed and be connected with the gun and the
signalling apparatus in various ways. For example, as shewn at Figure 2, both
the instrument and the gun may be connected directly or by gearing with contact
levers ¹² which, according to their position; include more or less resistance of the
rheostats and w² in circuit with the coils of the instrument G, constructed as a
differential galvanoscope, which, on the circuit being connected with any source of
electricity, can only take up the middle position when the positions of the two
contact levers coincide with each other.
Opposite the middle position of the galvanoscope is a contact spring c² or equi-
valent device which makes conducting contact with the pointer of the galvanoscope
as soon as this latter plays into the middle position, thus rendering possible
the closing of the firing circuit. Instead of the arrangement shewn, a variety of
others having the same effect may be used. Thus both contact levers and the one
coil of the galvanoscope together with the resistances W' and W2 may be connected
in series, as shewn at Fig. 3, and a constant resistance W be included in the circuit
of the second coil of the galvanoscope, so that the latter will only play into the
middle position when WW2 = W, the coil resistances of the galvanoscope,
being taken as equal.
In order to eliminate the surface resistance of the contact levers, any form of
Wheatstone's bridge, or equivalent device may be employed, in which case the
galvanoscope need not be a differential instrument, but only have a single coil as
indicated at Fig. 4.
In order to effect the contact in the middle position with the greatest possible
certainty, it is advisable to employ a relay with three positions, which can have
either single or differential coils, as indicated at Fig. 5. A permanent magnet M
pivotted at O plays between the poles of two electro magnets m¹ and m² and is con-
nected by a jointed rod S with the armature T held away by springs. As soon as
a current passes in the one direction or the other, the armature will be attracted
forcibly by the two bar magnets against the action of the springs F' F³, and by
the attraction of the magnet M in one direction or the other, according to the
direction of the current, it is made to assume an angular position, forming an elbow
with S.
On the cessation of the current the springs F1, F2, draw the armature away from
the electro magnets, and the apparatus returns to its middle position, from which
it is only deflected when the electro magnets are rendered active again.
With the above arrangement a contact e² may easily be applied, which, in the
middle position, makes contact with the armature T and effects the closing of the
firing circuit.
The above described arrangements may also be employed for bringing into and
out of action braking or stopping devices which prevent the gun from being moved
in the wrong direction by the gunners, or for putting in and out of action motor-
engines for automatically training the guns. This may be effected by providing,
in addition to the contact c² for the middle position, other contacts for the lateral
positions, through which circuits serving to effect these operations, are closed.
When using command apparatus, an arrangement will be employed which may
be similar to that shewn at Fig. 6 where the pointer Z touches the contact in the
middle. position and the contact c or 3 in the lateral positions.
In using the above described relay for 3 positions only the contacts c¹ and c³
Fig. 5 have to be added, which are touched by the permanent magnet M or an
extension thereof when in its lateral positions, whereupon the circuits required for
the said operations will be closed.
If it be desired to prevent the gunners from turning the gun. in the wrong
direction, brakes or stops- acting in one direction of suitable known arrangement
may be employed which are put in and out of action by the electric current on
closing and opening the circuit.
If on the other hand the automatic movement of the gun by means of motor-.

page_text: engines is to be effected by lateral contacts, various arrangements may be employed;
for instance, the motor may be kept running continuously in one and the same
direction, and the lateral contacts may be made to effect the motion of a coupling
device in the one direction or the other, the coupling being out of gear in the
middle position, so that the motion of the motor will be transmitted to the gun in
the one direction or the other, or not at all, according to the position of the contact
making device.
Fig. 7 shews an example for such an arrangement of an electric coupling device.
The motor is made to drive the shaft W on which is mounted the sleeve H con-
nected thereto by feather and groove, so as to rotate with but slide along the shaft
to an extent limited by the stops L¹ L².
The sleeve carries at each end an iron coned friction disc F1 and F2 and between
these is situated a bevil friction wheel For an axis at right angles to W, this
wheel being out of contact with both F and F2 when the sleeve H is in the middle
position. Each friction disc F' and F2 is surrounded by a solenoid coil S¹ and S2
and on closing the circuit of one such coil the corresponding disc is converted into
an electro-magnet which is consequently attracted to the friction wheel F and is
thus made to impart its rotation to the latter.
Thus according as the current is made to pass through the coil S¹ or S², F¹ or F2
is made to gear with wheel F and to effect its rotation in the one direction or the
other by the motor, and this motion of F is then transmitted in any suitable
manner to the gun. When no current is passing through either coil, the discs F¹ F²
do not impart any motion to the wheel F, and the gun remains stationary.
Instead of employing an electrically actuated coupling for the above purpose,
with a constantly rotating motor, the latter may be made to run either in one
direction or the other by making either of the two lateral contacts c¹ or c³, and to
remain stationary when the contact making device is in the middle position.
Fig. 8 shews an example of such an arrangement with an electro motor M t, with
which are combined the arrangement at Fig. 4 and the relay with three contacts
shewn at Fig. 5.
According as the magnet M of the relay inclines to the one side or the other, it
makes contact with either e' or c³, thereby short circuiting the one or other of the
oppositely wound coils 12 of the field magnet limbs of the electro motor M t, and
thus producing rotary motion in one direction or the other of the rotary armature,
while in the middle position of M neither of the contacts c¹ c³ are closed, and the
coils being connected in scries the currents therein neutralize each other,
thereby stopping the motor. If now the motor is geared to the turning mechanism
of the gun, the latter can be turned thereby in either direction for bringing it into
position on actuating the sending apparatus. On the position of the gun being
made to correspond with the position of the sending instrument M will assume the
middle position, and the armature T, in making contact with 2, the firing circuit
will be closed and the gun can be fired.
In a similar way, any other reversible motor can be governed electrically by the
contacts el 3: It will be readily understood that in place of a single galvanoscope,
several such may be connected either in series or in parallel, if it should be
considered necessary. Thus in the arrangement at Fig. 4, in order to increase the
sensitiveness, the closing of the contact 2 may be effected by a very sensitive
relay R, and the direction in which the adjustment is to be effected be indicated by
a second special galvanoscope, as shewn at G Fig. 9. If the adjustment of the
gun is to be effected by a motor engine, the galvanoscope G may be provided with
the two side contacts c¹ and e3 which effect the motion in the one direction or the
other, or the motor engine may be governed by an independent person from any
point by an entirely separate circuit according to the indications of the galvano-
meter G.
It is also quite possible to actuate several receiving apparatus from one
and the same sending apparatus, so that the latter may be used to adjust simul-
taneously several guns.
The arrangements become more complicated if the gun is not only to be adjusted

page_text: according to the sighting instrument, but also according to certain corrections,
relative to elevation, horizontal distance &c. In this case the necessary corrections
can be effected either at the sending or at the receiving instrument, either by
shifting the zero position of the sending or receiving instrument relatively to the
zero position of the gun, or by altering the ratio of the resistances by stoppering &c.,
so as to effect a shifting of the sending instrument relatively to the receiving
instrument.
Assume for instance that with regard to the vertical adjustment of a gun an
elevation of 5° from the sighting line has to be given on account of a certain
range and that the adjusting of the gun is effected automatically according to a
sighting apparatus which is connected with the sending instrument of one of the
above described transmitting apparatus. In order now to adjust the elevation of
the gun to the above mentioned 5° relatively to the sighting line, the axis of the
sighting telescope must either be turned downwards to the extent of 5° in the first
instance relatively to its normal relative position to the sending instrument, or the
axis of the gun must be turned upwards to the same extent relatively to the
contact.
The desired end may however also be attained by placing the receiver in
advance of the sending instrument to the extent of the said angle, by modifying
the resistances in the arrangements shown at Figures 2, 3 and 4.
This is effected for example in Fig. 2 by the inclusion or exclusion of a resistance
corresponding to the desired correcting angle in the respective branch of the
differential galvanometer; in Figure 3 for example, by increasing or decreasing
the resistance W, or by including or excluding a corresponding resistance in the
circuit passing through the contact lever and 2 or in Fig. 4 by including or
excluding additional resistances in one of the four branches of the bridge.
It may happen, for example, in coast forts, where the objects aimed at are only
situated on a plane surface (surface of the water) and where in consequence of a
relatively high position of the sighting instrument, the inclination thereof to the
horizontal affords a sufficient indication of the distance, that with every adjustment
of the sighting instrument the direction of the gun corresponding thereto shall be at
once corrected to the extent required for the distance. In order to attain this, it
would be necessary either to provide an unequal mechanical transmission from the
sighting instrument to the sending instrument corresponding to the different
elevations, such as cams, or the correction would have to be allowed for by an
unequal division of the resistance from the sending to the receiving instrument.
. If for instance the resistance wire of the sending instrument were to have a
gradually decreasing section, the position of the receiving instrument would always
be rather higher than that of the sending instrument, and in suitably determining
the proportious, the difference could be made to compensate for the varying
elevation.
The above described arrangement could, in the absence of a fixed base, only be
used in combination with a heeling indicator which would keep the firing circuit
interrupted until the base (ship's deck) assumed a certain heeling angle.
Dated this 28th day of November 1890
ABEL & IMRAY,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Appliances for Facilitating the Training and Firing of Guns.
We, SIEMENS BROTHERS & Co. LIMITED of 12 Queen Anne's Gate,
Westminster in the County of Middlesex, Electrical Engineers 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 the application to guns of electrical and other appliances

page_text: for effecting the training or bringing into firing position thereof as also for effecting
the firing of the gun by the officer in charge situated in a central position at a
distance from the gun, or by others executing his commands, the arrangement being
such that the firing cannot be effected until the gun has been brought into the exact
position required.
In most cases the officer in charge will employ a separate sighting instrument or
range finder and will effect the adjustment of the gun according to the indications
obtained by this; but this instrument might also be combined with the actuating
mechanism, so that the adjustment of the gun will always depend upon the adjust-
ment of the sighting instrument and the officer in charge will only have to adjust
the latter and give the command to fire, or, with electric firing, effect this himself,
such firing being however prevented as long as the position of the gun does not
correspond to that of the sighting device.
The dependence of the firing upon the correct adjustment of the gun can be
ensured by causing an electric circuit (which serves either to convey the
command, or to fire electrically, or to release electrically a mechanical firing
device) to be interrupted as long as the direction of the gun does not coincide
with that of the sighting device, and only to be closed when such coincidence
takes place.
By means of the apparatus which forms the subject of the present invention, the
training or adjustment of the gun can be effected both laterally and vertically, as
also simultaneously in both directions combined, and the firing can be made to
depend upon the correct adjustment in each of the two directions.
In order to facilitate the description of the various modes of carrying out this
invention we shall first describe the simplest case, namely that in which the
horizontal adjustment of the gun is effected by the gunners according to indications
of a command apparatus.
Referring to Fig. 1 of the drawings accompanying our Provisional Specification,
the receiver E of the command apparatus, which may be of any of the known
electric, mechanical, pneumatic &c. constructions, is attached to the pivot pedestal l'
of the gun so that its pointer Z can turn round the vertical axis of the gun, and
points directly to the position into which the gun is to be brought. The gun R
carries a contact spring which makes a conducting contact with the pointer Z as
soon as both parts lie in exactly the same direction, thereby closing a firing circuit
enabling the gun to be fired.
The receiver of the command apparatus might also be combined with the gun
itself, so that the pointer thereof can rotate upon the vertical pivot axis of the gun,
but the whole receiving apparatus, with its pointer follows the movements of the
gun, and in this case the position of the pointer relatively to a fixed directing line,
or the relative distance of a part of the pointer from an externally situated fixed
point, may serve to indicate the required adjustment of the gun. The latter would
in this case have to be turned in such a manner that the pointer is made to coincide
with the fixed point in order to enable the firing to be effected.
The command apparatus may consist of a galvanoscope with three positions,
namely a middle position for the correct adjustment of the gun, and two side
positions for indicating the direction in which the gun is to be moved. This
galvanoscope can be variously constructed and connected with the gun, and the
signalling apparatus in various ways. For example, as shown at Figure 2, both
the instrument and the gun may be connected directly or by gearing with contact
levers which, according to their position, include more or less resistance of
the rheostats w¹ and w² in circuit with the coils of the instrument G, constructed as
a differential galvanoscope, which on the circuit being connected with any source
of electricity can only take up the middle position when the positions of the two
contact levers coincide with each other.
Opposite the middle position of the galvanoscope is a contact spring c² or
equivalent device which makes conducting contact with the pointer of the galvano-
scope as soon as this pointer plays into the middle position, thus rendering the

page_text: closing of the firing circuit possible. Instead of the arrangement shewn, a variety
of others having the same effect may be used. Thus both contact levers and the
one coil of the galvanoscope together with the resistances W and W² may be
connected in series, as shewn at Figure 3, and a constant resistance W may be
included in the circuit of the second coil of the galvanoscope, so that the latter will
only play into the middle position when W+WW, the coil resistances' of the
galvanoscope, being taken as equal.
In order to eliminate the surface resistance of the contact levers, any form of
Wheatstone's bridge, or equivalent device may be employed, in which case the
galvanoscope need not be a differential instrument, but may have only a single coil
as indicated at Figure 4.
In order to effect the contact in the middle position with the greatest possible
certainty, it is advisable to employ a relay with three positions, which can have
either single or differential coils, as indicated at Figure 5. A permanent magnet M
pivotted at O plays between the poles of two electro-magnets m¹ and m² and is
connected by a jointed rod S with the armature T held away by springs. As soon
as a current passes in the one direction or the other, the armature will be attracted
forcibly by the two bar magnets against the action of the springs F1 F2 and by the
attraction of the magnet M in one direction or the other, according to the
direction of the current, it is made to assume an angular position, forming an elbow
with S.
On the cessation of the current the springs F1 F2 draw the armature J away
from the electro magnets, and the apparatus returns to its middle position, from
which it is only deflected when the electro magnets are rendered active again.
With the above arrangement a contact 2 may easily be applied, which in the
middle position, makes contact with the armature J and effects the closing of the
firing circuit.
The above described arrangements may also be employed for bringing into and
out of action braking or stopping devices which prevent the gun from being
moved in the wrong direction by the gunners, or for putting into and out of action
motor engines for automatically training the guns. This may be effected by
providing, in addition to the contact 2 for the middle position, other contacts
for the lateral positions, to close circuits serving to effect the operations above
mentioned.
When using command apparatus, an arrangement will be employed which may
be similar to that shewn at Figure 6 where the pointer Z touches the contact c² in
the middle position and the contact c¹ or c³ in the lateral positions.
In using the above described relay for 3 positions only, the contacts c' and c³
Figure 5 have to be added, so as to be touched by the permanent magnet M or an
extension thereof when in its lateral positions, whereupon the circuits required for
the said operations will be closed.
If it be desired to prevent the gunners from turning the gun in the wrong
direction, brakes or stops acting in one direction of suitable known arrangement
may be employed, which are put in and out of action by the electric current on
closing and opening the circuit.
If, on the other hand, the automatic movement of the gun by means of motor
engines is to be effected by lateral contacts, various arrangements may be
employed; for instance, the motor may be kept running continuously in one and
the same direction, and the lateral contacts may be made to effect the motion of a
coupling device in the one direction or the other, the coupling being out of gear in
the middle position, so that the motion of the motor will be transmitted to the gun
in the one direction or the other, or not at all, according to the position of the
contact making device.
Figure 7 shews as an example such an arrangement of electric coupling device.
The motor is made to drive the shaft W on which is mounted the sleeve H
connected thereto by feather and groove, so as to rotate with but slide along the
shaft to an extent.limited by the stops L₁ L'.

page_text: The sleeve carries at each end an iron coned friction disc F' and F2 and between
these is situated a bevil friction wheel F on an axis at right angles to W, this
wheel being out of contact with both F1 and F2 when the sleeve H is in the middle
position. Each friction disc F1 and F2 is surrounded by a solenoid coil S¹ and S²,
so that on closing the circuit of one such coil the corresponding disc is converted
into an electro magnet which is consequently attracted to the friction wheel F and
is thus made to impart its rotation to the latter.
Thus according as the current is made to pass through the coil S¹ or S², F¹ or F2
is made to gear with the wheel F, and to effect its rotation in the one direction or
the other by the motor, and this motion of F is then transmitted in any suitable
manner to the gun. When no current is passing through either coil, neither
of the discs F1 F2 imparts any motion to the wheel F, and the gun remains
stationary.
Instead of employing an electrically actuated coupling for the above purpose,
with a constantly rotating motor, the latter may be made to run either in one
direction or the other by making either of the two lateral contacts c¹ or c³, and to
remain stationary when the contact making device is in the middle position.
Fig. 8 shews an example of such an arrangement with an electro motor Mt, with
which are combined the arrangement shewn in Fig. 4 and the relay with three
contacts shewn in Fig. 5.
According as the magnet M of the relay inclines to the one side or the other, it
makes contact with either c¹ or c³, thereby short circuiting the one or other of the
oppositely wound coils 62 of the field magnet limbs of the electro motor Mt, and
thus producing rotary motion in one direction or the other of the rotary armature,
while in the middle position of M neither of the contacts c' c³ are closed, and the
coils being connected in series the currents therein neutralize each other,
thereby stopping the motor. If now the motor is geared to the turning mechanism
of the gun, the latter can be turned thereby in either direction for bringing it into
position on actuating the sending apparatus. On the position of the gun being
made to correspond with the position of the sending instrument, M will assume the
middle position, and the armature T in making contact with c², the firing circuit
will be closed and the gun can be fired.
In a similar way any other reversible motor can be governed electrically by the
contacts c¹³. It will be readily understood that instead of a single galvanoscope,
several such may be connected either in series or in parallel, if it should be
considered necessary. Thus in the arrangement Fig. 4, in order to increase the
sensitiveness, the closing of the contact may be effected as shewn in Figure 9 by
a very sensitive relay R, and the direction in which the adjustment is to be effected
may be indicated by a second special galvanoscope. If the adjustment of the gun
is to be effected by a motor engine, the galvanometer G may be provided with the
two side contacts c' and c³ (Fig. 5) which effect the motion in the one direction or
the other, or the motor engine may be governed by an independent person from
any point by an entirely separate circuit according to the indications of the
galvanometer G. It is also quite possible to actuate several receiving apparatus
from one and the same sending apparatus, so that the latter may be used to adjust
simultaneously several guns.
The arrangements become more complicated if the gun is not only to be adjusted
to the sighting instrument, but also according to certain corrections, relative to
elevation, horizontal distance and the like. In this case, the necessary corrections
can be effected either at the sending or at the receiving instrument, either by
shifting the zero position of the sending or receiving instrument relatively to the
zero position of the gun, or by altering the ratio of the resistances by stoppering &c.,
so as to effect a shifting of the sending instrument relatively to the receiving
instrument..
If it be assumed, for instance, that with regard to the vertical adjustment of
a gun, an elevation of 5° from the sighting line has to be given on account of a
certain range, the adjusting of the gun is effected automatically according to a

page_text: sighting apparatus which is connected with the sending instrument of one of the
above described transmitting apparatus. In order now to adjust the elevation of
the gun to the above mentioned 5° relatively to the sighting line, the axis of the
sighting telescope must either be turned downwards to the extent of 5° in the first
instance relatively to its normal relative position to the sending instrument, or the
axis of the gun must be turned upwards to the same extent relatively to the
contact.
The desired end may however also be attained, by placing the receiver in
advance of the sending instrument to the extent of the said angle, by modifying
the resistances in the arrangements shewn at Figs. 2, 3 and 4.
This is effected, for example, in Figure 2 by the inclusion or exclusion of a
resistance corresponding to the desired correcting angle in the respective branch of
the differential galvanometer; in Fig. 3 for example, by increasing or decreasing
the resistance W, or by including or excluding a corresponding resistance in the
circuit passing through the contact lever and h² or in Fig. 4 by including or
excluding additional resistances in one of the four branches of the bridge.
It may happen, for example, in coast forts, where the objects aimed at are only
situated on a plane surface (surface of the water) and where in consequence of a
relatively high position of the sighting instrument the inclination thereof to the hori-
zontal affords a sufficient indication of the distance, that with every adjustment of the
sighting instrument the direction of the gun corresponding thereto shall be at once
corrected to the extent required for the distance. In order to attain this, it would
be necessary either to provide an unequal mechanical transmission from the sighting
instrument to the sending instrument corresponding to the different elevations, such
as cams, or the correction would have to be allowed for by an unequal division of
the resistance from the sending to the receiving instrument.
If, for instance, the resistance wire of the sending instrument were to have a
gradually decreasing section, the position of the receiving instrument would
always be rather higher than that of the sending instrument, and in suitably
determining the proportions, the difference could be made to compensate for the
varying elevation.
The above described arrangement could, in the absence of a fixed base, only be
used in combination with a heeling indicator which would keep the firing circuit
interrupted until the base (ship's deck) assumed a certain heeling angle.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. An electrical arrangement for training and directing also electrically firing
guns actuated from a central position, wherein two or more resistances W! W
varied in their connections by means of a transmitter H' and a receiver H²,
are combined with a galvanoscope or relay, the needle or armature of which
being moved until the receiver takes the position determined by the transmitter,
effects closing of electrical circuits, substantially as herein described.
2. In the relay employed in the arrangement above referred to, the combina-
tion of the ends m² m² of the cores of two electro-magnets with the pivotted
bar magnet M, for making contact with the one or the other of the terminals c¹ c³,
and with the spring armature T and its jointed connection to the bar magnet M,
substantially as and for the purpose set forth.
3. In the arrangement referred to in Claim 1 the electrical coupling substantially
as described with reference to Fig. 7.
Dated this 18th day of August 1801
ABEL & IMRAY,
Agents for Applicants.