Year: 1886

page_text: Date of Application, 30th Oct., 1836.
Complete Left, 2nd Aug., 1887.
Complete Accepted, 6th Sept., 1887.
I JAMES GRIEVE LORRAIN, of Norfolk House, Victoria Embankment, London,
Consulting Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to improvements in Electric Telephony whereby certain
advantages are obtained.
In the complete specification accompanying my Letters Patent No. 15,147 of the
year 1885 I describe, under the reference letter (A), telephonic installations in which
condensers or other so called statical instruments are employed both as transmitters
and as receivers, two converters being employed one placed at each station. In these
installations a low tension circuit, common to the two converters, extends between the
two stations; and the high tension circuits of the said converters at the two stations
contain the transmitting and receiving condensers, or other statical instruments. In
the said specification I set forth that the high tension circuits at each station contain
charging batteries, the low tension circuit containing no battery.
In my present invention, however, I place in this low tension circuit a primary
battery, or other suitable source or reservoir of electrical energy. This battery, which
I may call for convenience a " feeding battery" to distinguish it from the charging
batteries employed in the high tension circuits to charge the condensers, may be
connected up in the said low tension circuit in any convenient known manner.
When desired I may employ more than one converter at a station; and when I so
employ more than one converter I may connect up the low tension conductors of the
said converters in the low tension circuit either in series or in multiple arc, and
similarly I may connect up the high tension conductors of the said converters in the
high tension circuit or circuits either in series or in multiple arc.
may place the condensers either in the main high tension circuits, or in shunt or
derived circuit therefrom.
I may substitute for the condensers as above mentioned any of the instruments
specified in the complete Specifications accompanying my Letters Patent numbered
10,504 of the year 1884, 11,307 of the year 1884, and 2, 117 of the year 1885.
Dated this 30th day of October 1886.

page_text: I, JAMES GRIEVE LORRAIN, of Norfolk House, Victoria Embankment, London, W.C.,
Consulting Engineer, 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 :-
My invention relates to improvements in Electric Telephony whereby certain
advantages are obtained.
In the complete specification accompanying my Letters Patent No. 15147 of the
year 1885, I describe, under the reference letter (A), telephonic installations in which
condensers or other so called statical instruments are employed both as transmitters
and as receivers, two converters being employed one placed at each station. In these
installations a low tension circuit common to the two converters extends between the
two stations; and the high tension circuits of the said converters at the two stations
contain the transmitting and receiving condensers, or other statical instruments.
In the said specification I set forth that the high tension circuits at each station
contain charging batteries, the low tension circuit containing no battery.
"
In carrying out my present invention however I place in this low tension circuit a
primary battery or other suitable source or reservoir of electrical energy. This battery,
which I may call for convenience a
1
feeding battery" to distinguish it from the
charging batteries employed in the high tension circuits to charge the condensers,
may be connected up in the said low tension circuit in any convenient known manner.
In my Provisional Specification I referred to the employment of more than one
converter at a station. I have since ascertained by experiment that the employment
of more than one converter at a station offers no advantage; and I therefore make no
further reference thereto in my present Complete Specification.
I place the condensers preferably in the main high tension circuits, but for
convenience of arrangement I may sometimes place them in shunt or derived circuit
therefrom.
Having thus described the nature of my said Invention for Improvements in
Electric Telephony, I shall now proceed to describe more in detail the manner in which
it is to be or in which it may be performed or carried into effect: and in order that
this more detailed description may be readily understood I have annexed hereunto two
sheets of drawings diagrammatically illustrative of my said invention, and have inserted
in the same figures and letters of reference corresponding with those in the following
explanation.
In figure 1 only one condenser is shown at each station, that at station X being
assumed in the following explanation to be a transmitter, and that at station Y a
receiver. C is the transmitting instrument arranged in the fine wire or high tension
circuit J of the converter A in which circuit is also the primary battery Ď or other
source or reservoir of high tension electrical energy serving to charge the transmitting
instrument. This circuit J is purely local, and does not extend between the two

page_text: stations. K is the other or thick wire or low tension circuit common to the two
converters A and A' and extending between the two stations X and Y. A' is the
converter at station Y and its high tension circuit J¹ has in it the receiving
instrument C¹ and the source or reservoir of high tension electrical energy D¹ used to
charge it. B is the feeding battery in the low tension circuit K. The action is as
follows. The circuit J and the transmitting instrument C are highly charged by D
and this charge is varied by the action of the voice on C. This variation in I will, as
will be readily understood from the well known action of the converter, cause variations
to be set up in the current flowing through K. Similarly the variations in the current
flowing through K will set up corresponding variations in J', and these variations will
increase and decrease the charge in R₁ and cause it to emit sounds and speak.
Figures 2, 3 and 4 are diagrams somewhat similar to figure 1 except that in
the instances illustrated by these diagrams there are two instruments at each station,
one for use as a transmitter and the other for use as a receiver. In figure 2 the
transmitting and receiving instruments are arranged in series with the charging
battery in which case it will be seen that only one of the elements or series of elements
of each instrument can be directly charged by the charging battery the other element
or series of elements being charged so far as the charging battery is concerned solely
by induction. In figure 3 the transmitting and receiving instruments at each station
are arranged in parallel or multiple are with the charging battery in which case it
will be seen that both elements or series of elements of the said instruments are directly
charged and with electricity of opposite sign by the charging battery. In figure 4 the
circuit J is split into two parts (one being practically a shunt or derived circuit from
the other) in one of which is the transmitter and in the other the receiver each
provided with a separate battery. The drawing of the connections at the two stations
in this figure are different but practically they are equivalent.
The object and effect of employing the feeding battery B is to increase the clearness
and distinctness with which speech and other sounds are reproduced.
I find that on a short line I get good effects by employing as a feeding battery
two small Leclanché cells coupled up in quantity, and as charging batteries twelve
minute Leclanché cells, of the type known as medical cells, coupled up in series.
For long lines the number of cells constituting the feeding battery may be increased
with advantage, such increased number being arranged so as to increase the electro-
motive force of the battery.
I may when desired substitute for the condensers as above mentioned any of the
instruments specified in the complete Specification accompanying my Letters Patent
numbered 10,505 of the year 1884, 11307 of the year 1884, and 2117 of the
year 1885.
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 :-
In cases wherein condensers or other so called statical instruments are used both as
transmitters and receivers the improvement in Electric Telephony consisting in the
use of a feeding battery substantially as and for the purposes set forth.
DL Dol 1
ст 1. 1007
J. G. LORRAIN.