Improvements in and connected with Electric Relays.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in and connected with Electric Relays.
A communication from abroad by ALBERT CUSHING CREIORE, 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:-
This invention relates to the adaptation of the Lippmann capillary electro-
meter to relay purposes.
In Lippmann's electrometer a glass tube drawn down to capillary size at
its lower end and containing mercury has its lower end immersed in a vessel
containing dilute sulphuric acid and a layer of mercury, the end of the tube
Terminals of an
being at some distance above the mercury in the vessel.
electric circuit are connected to the mercury in the tube and in the vessel
respectively. The dilute acid rises in the tube by capillary attraction and raises
the mercury therein to a certain point. On completing the electric circuit to
the dilute acid through the mercury in the vessel and to the mercury within
the capillary tube, the existence of potential between the dilute acid and the
mercury in the capillary tube causes the meniscus formed between their surfaces
to rise a still further distance, and any subsequent variation in potential, within
proper limits, results in an almost directly proportional movement of the
meniscus.
Upon this phenomenon the present invention is based. The circuit whose
fluctuations or variations in potential are to be utilized is connected to the
mercury in the tube and in the vessel of a capillary device such as that just
described and the device is provided with suitable means, e.g., a device for
multiplying motion, whereby the movement of the mercury in the tube can
open or close or vary the resistance of another or local circuit.
The accompanying drawing is a diagram illustrating one way in which the
invention may be carried into practical effect.
1 represents a capillary mercury tube of the electrometer; and 2 a vessel
containing dilute sulphuric acid and mercury for making contact therewith-
this vessel is preferably open to the air, its cork being perforated at 3; 4 the
mercury in the capillary tube: 5 the meniscus between the mercury and the
dilute acid and 6 and 7 wires for the circuit that actuates the relay. The tube 1
is sealed and the space above the mercury therein may be filled with some
liquid of slight compressibility, such as oil in which may be situated a
receptacle 8 one or both sides of which are metallic diaphragms which are insu-
lated from each other and connected in the local circuit 9 and between which
is placed a suitable material, such as carbon granules, whose resistance will

page_text: vary with variations of pressure. In the local circuit 9 there is placed a device
which is responsive to these resistance variations and whereby they can be utilized
in the manner desired. This device may, for example and as indicated in the
diagram, be a Wheatstone bridge, in one leg of which the variable resistance S
is placed, the other legs each having a fixed resistance and the bridging resistance
being the operating coil 10 of any suitable indicator or recorder—for instance,
a syphon recorder.
It is clear from the above description that a change of potential at 6, 7 will
produce a movement of the meniscus 5 which will result in a variation in height
of the mercury in the tube 1 and consequently a variation of pressure on the
diaphragms of the receptacle S, and will thus bring about a change in the
resistance of the pressure-sensitive material in the said receptacle and an
unbalancing of the bridge and consequently a flow of current through the coil 10
whereby an indication of record will be produced.
It is obvious that the movements of the meniscus may be transmitted in a
purely mechanical manner to that on which the changes in the main circuit are
to be impressed and that the movements of the mercury in the tube 1 may be
made to act upon a variable resistance in ways other than that indicated
diagrammatically.
The meniscus is very sensitive and rapid in its movements and therefore
capillary relays such as hereinbefore described are well suited for use as a
receiver for submarine cables--it may be, in conjunction with means for pre-
venting the relay from being subjected to a potential higher than that at which
it will operate satisfactorily. The range of usefulness of such capillary relays
is, however, very wide, since they respond quickly to exceedingly small changes
of potential, the movements of the meniscus are approximately proportional to
differences of potential and they are also dead beat.
Dated this 901 1. of W1 100
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Chartered Patent Agent.
POST and connected with Electric Relays.
A 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, formerly of Fortress Monroe,
Elizabeth City County, State of Virginia, but now of Washington, District
of Columbia, United States of America, Captain in the United States
Army.
T, 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 the adaptation of the Lipmann capillary electro-
meter to relay purposes.
In Lipmann's electrometer a glass tube drawn down to capillary size at its
lower end and containing mercury has its lower extremity immersed in a vessel
containing dilute sulphuric acid and a layer of mercury, the said extremity of

page_text: the tube being at some distance above the mercury in the vessel. Terminals of
an electric circuit are connected to the mercury in the tube and in the vessel
respectively. The dilute acid rises in the tube by capillary attraction and raises
the mercury therein to a certain point. On completing the electric circuit to
the dilute acid through the mercury in the vessel and to the mercury within the
capillary tube, the existence of potential between the dilute acid and the mercury
in the capillary tube causes the meniscus formed between their surfaces to rise
further, and any subsequent variation in potential, within proper limits, results
in an almost directly proportional movement of the meniscus.
Upon this phenomenon the present invention is based. The circuit whose
fluctuations or variations in potential are to be utilized is connected to the
mercury in the tube and to that in the vessel of a capillary device such as that
just described, and the device is provided with suitable means, whereby the
movement of the mercury in the tube can open or close, or vary the resistance
of, another or local circuit.
The drawing filed with my Provisional Specification is a diagrammatic repre-
sentation of one example of apparatus according to this invention.
1 represents a capillary mercury tube such as that of the electrometer; 2 a
vessel containing dilute sulphuric acid and mercury for making contact there-
with--this vessel is preferably open to the air, its cork being perforated at 3;
4 the mercury in the capillary tube; 5 the meniscus between the mercury and
the dilute acid; and 6 and 7 'wires for the circuit that actuates the relay. The
tube 1 is sealed and the space above the mercury therein may be filled with
some liquid or fluid of slight compressibility, as oil, in which may be situated a
receptacle 8 one or both sides of which are metallic diaphragms which are
insulated from each other and connected in the local circuit 9 and between which
is placed a suitable material as, for instance, carbon granules, whose resistance
will vary with variations of pressure. In the local circuit 9, there is placed a
device which is responsive to these resistance variations and whereby they can
be utilized in the manner described. This device may, for example, and as
indicated in the diagram, be a Wheatstone bridge, in one leg of which the
variable resistance 8 is placed, the other legs each having a fixed resistance and
the bridging resistance being the operating coil 10 of any suitable indicator or
recorder for instance, a siphon recorder.
It is clear from the preceding description that a change in the difference of
potentials at 6 and 7 will produce a movement of the meniscus 5 which will
result in a variation in height of the mercury in the tube 1, and consequently
a variation of pressure on the diaphragms of the receptacle 8, and will thus bring
about a change in the resistance of the pressure-sensitive material in the said
receptacle and an unbalancing of the bridge, and consequently a flow of current
through the coil 10, whereby an indication or record will be produced.
The meniscus is very sensitive and rapid in its movements, and therefore
capillary relays such as hereinbefore described are well suited for use in con-
nexion with receivers for submarine cables--it may be, in conjunction with means
for preventing the relays from being subjected to potentials higher than that
at which they will operate satisfactorily. The range of usefulness of such
capillary relays is, however, very wide, since they respond quickly to exceedingly
small changes of potential, the movements of the meniscus are approximately
proportional to differences of potential, and they are also dead heat.
In some cases the receiving apparatus may be directly inserted in the local
circuit.
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 combination with a Lippmann-electrometer capillary device, of a body
or column of liquid subject to the action of the meniscus, and means actuated

page_text: by the said column of liquid for controlling an electric circuit, substantially as
described.
2. The combination with a Lippmann-electrometer capillary device, of a closed
space or chamber above the mercury and filled with a fluid of slight com-
pressibility, and a current-varying device located in the said fluid and operated
by the rise and fall of the mercury.
3. The combination with a Lippmann-electrometer capillary device, of a closed
space or chamber above the mercury and filled with a fluid of slight compressi-
bility, a receptacle located in the said chamber and having flexible walls, a
variable resistance within the said receptacle, an electric circuit containing the
said resistance and an auxiliary source of electricity, and an indicator or recorder
adapted to receive current from the said source as determined by variations of
the said resistance, for the purpose set forth.
4. A capillary device such as employed in a Lippmann-electrometer, in which
a confined body of liquid in contact with the mercury in the capillary tube has
immersed in it a flexible receptacle containing material adapted to form part
of an electric circuit and to offer, to the passage of current, resistance varying
with its degree of compression.
5. Apparatus constructed, arranged, and operating substantially as herein-
before described with reference to and shown in the drawing filed with my
Provisional Specification.
ember 1899.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Chartered Patent Agent.