IMPROVEMENTS IN ELECTRIC TELEPHONY
Year: 1885

page_text: I, JAMES GRIEVE LORRAIN, of 3 Vernon Chambers, Southampton Row, in the
County of Middlesex, Consulting Engineer, do hereby declare the nature of my
invention for IMPROVEMENTS IN ELECTRIC TELEPHONY to be as follows:-
My invention relates to improvements in Electric Telephony, and has reference
more particularly to telephone systems wherein condensers are used either as
transmitters or as receivers or as both, or wherein transmitters or receivers acting
on the statical principle are employed. When such instruments are employed with
a charging battery producing a high electromotive force the expense is considerable
on account of the number of cells of a primary battery which require to be coupled
up in series. As the current strength required is very small these cells may be
made of very small size, but even small primary batteries are expensive, their
internal resistance is high, (thereby greatly increasing the resistance of the circuit
and so lessening the rapidity with which statical charge and discharge take place),
they are troublesome to keep clean and in order, and their lives are comparatively
short.
By my invention I employ as charging batteries for the transmitting and
receiving instruments series of secondary couples or accumulators arranged so
that they can be themselves charged in quantity by a primary battery, or other
source of electricity, and then when required arranged in series for charging the
transmitters or receivers or complete circuit.
In carrying my invention into effect I employ secondary couples or accumulators
whose number may be determined by the electromotive force required. These may
be in connection, by spring or rubbing contacts or otherwise, with an arrangement,
such for example as that known as a Planté commutator, for grouping the
secondary cells in quantity or in series as desired. In addition to the secondary
cells I may employ a primary battery for charging them; and this primary battery
may be in connection with the commutator arrangement above mentioned in such
manner that when the secondary cells are joined up in quantity the current from
the primary battery will charge them and when the secondary cells are joined up
in series to charge the transmitters or receivers or circuit, the primary battery will
be cut out of circuit. The commutator may be operated directly by hand or by
an automatic switch caused to act by the addition or removal of the transmitter
or receiver or calling or signalling, apparatus after the manner of the automatic

page_text: switches at present employed for switching line on to call bell or telephone, or by
a mercury reversal switch or otherwise. This automatic switch may be fastened
direct to the commutator or may operate it by means of a rod or cord or other
equivalent mechanical device, or by an electromagnet or solenoid or other equivalent
electrical device.
The primary battery employed should be of such a kind or consist of such a
number of cells arranged in series as to give an electromotive force slightly in
excess of that of the secondary battery when its cells are arranged in quantity, so
as to make it impossible for the secondary battery to discharge itself through the
primary battery when in circuit. Thus if the cells of the secondary battery
consist of one of the well known forms of lead couple, Daniell cells, arranged
three in series, will give good results. The primary battery will then have an
electromotive force of about three volts which will be high enough to efficiently
charge the secondary battery without allowing the latter, whose electromotive force
will be say two to two and a half volts, to be discharged through it.
In the case where a condenser or other statical instrument is used as a receiver
and a microphone as a transmitter, the primary battery above mentioned may be
employed to actuate the microphone transmitter whilst out of circuit with and
therefore not employed in charging the secondary battery.
The primary battery used for charging the secondary couples may also be used
for signalling as for example by ringing a call bell as in the well known manner.

page_text: Improvements in Electric Telephony.
I, JAMES GRIEVE LORRAIN, of 3 Vernon Chambers, Southampton Row, in the
County of Middlesex, Consulting Engineer do hereby declare the nature of my
invention for IMPROVEMENTS IN ELECTRIC TELEPHONY and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement :-
My Invention relates to improvements in Electric Telephony and has reference
more particularly to telephonic systems wherein condensers are used (such for
example as those specified in Letters Patent No. 2907 of the year 1882) either as
transmitters or as receivers or as both, or wherein transmitters or receivers acting
on the statical principle are employed. When such instruments are employed with
a charging battery producing a high electromotive force the expense is considerable
on account of the number of cells of a primary battery which require to be joined
up in series. As the current strength required is usually very small these cells
may be made of very small size, but even small primary batteries are expensive,
their internal resistance is high, which appears to produce what apparently
resembles a retardive effect as if the rapidity with which the statical charge is
varied were lessened: they are troublesome to keep clean and in order and their
lives are comparatively short.
To avoid these drawbacks I employ as charging batteries, either for the trans-
mitting or the receiving instruments or for both, series of secondary couples or
accumulators arranged so that they can be themselves charged in quantity by a
primary battery or other source of electricity and then when required arranged in
series for charging the transmitters or receivers or the complete circuit.
In carrying my invention into effect I employ secondary couples or accumulators
whose number may be determined by the electromotive force required, and I also
employ a primary battery for the purpose of charging the said secondary batteries
or accumulators. These secondary couples or accumulators are arranged so as to
be capable of making connection by spring or rubbing contacts or otherwise with
an arrangement (hereinafter called a "coupler") such for example as that known
as a Planté commutator, and whose object is to group the secondary cells in
quantity or in series as hereinafter specified. The primary battery may also be in
connection with the coupler above mentioned in such manner that when the
secondary cells are joined up in quantity the current from the primary battery will
charge them and when the secondary cells are joined up in series to charge the
transmitters or receivers or both, the primary battery will be cut out of circuit.
I sometimes arrange the coupler so that it may be operated directly by hand but
I prefer to operate it by an automatic switch caused to act by the addition or
removal of the transmitter or receiver or calling or signalling apparatus after the
manner of the automatic switches at present employed for switching line on to
call-bell or telephone respectively and which are usually made to act by the
addition or removal of the receiver. This automatic switch is preferably fastened
direct to the coupler but I sometimes operate it by means of a rod or cord or other

page_text: equivalent mechanical device; or I may operate it by the pull of an electo-magnet
or other equivalent electrical device.
The primary battery employed should be of such a kind or consist of such a
number of cells arranged in series as to give an electromotive force slightly in
excess of that of the secondary battery when its cells are arranged in quantity so
as to make it impossible for the secondary battery to discharge itself through the
primary battery when in circuit. Thus if the cells of the secondary battery
consist of one of the well known forms of lead couple, Daniell cells arranged three
in series will give good results. The primary battery will then have an electro-
motive force of about three volts which will be high enough to efficiently charge
the secondary battery without allowing the latter, whose electromotive force will
be say two to two and a quarter volts to be discharged through it.
In the case where a condenser or other statical instrument is used as a receiver
and a microphone or other similar instrument as a transmitter I sometimes employ
the primary battery above mentioned, whilst out of circuit with and therefore not
employed in charging the secondary battery, to actuate the microphone or other
similar transmitter. In this case the secondary battery charges the receiver at the
remote station as will be readily understood.
I sometimes employ the primary battery, used for charging the secondary couples,
for signalling as for example by ringing a call-bell as in the well known manner.
I prefer to make the coupler somewhat similar in form to that employed in the
older forms of Ayrton-Perry dead-beat galvanometer therein used for arranging the
wire strands in quantity or series, and I attach a lever at right angles with
the drum of this. On this lever I prefer to hang either the transmitter or the
receiver as may be found most convenient in each case, and to this lever I attach a
counter-spring so as to move the drum round when the weight of the said trans-
mitter or receiver as the case may be, is removed.
I generally make the secondary couples of tubes containing two small strips or
prisms of lead immersed in dilute sulphuric acid.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
1. In a telephone system containing condensers or other statical instruments as
transmitters or receivers or both the use of secondary cells in connection with a
coupler and primary battery substantially as and for the purpose specified.
2. In a telephone system containing a microphone or other similar instrument
as transmitter and a condenser or other statical instrument as receiver the use of a
primary battery to alternately actuate the transmitter and charge the secondary
battery which charges the receiver substantially as specified.
T1000