Earth battery
Encyclopedia
An Earth battery is a pair of electrode
s made of two dissimilar metals, such as iron
and copper
, which are buried in the soil
or immersed in the sea
. Earth batteries act as water activated batteries
and if the plates are sufficiently far apart, they can tap telluric currents. Earth batteries are sometimes referred to as Telluric power sources and Telluric generators.
in 1841 in order to drive a prime mover
. Bain buried plates of zinc
and copper in the ground
about one meter apart and used the resulting voltage, of about one volt, to operate a clock. Carl Friedrich Gauss
, who had researched Earth's magnetic field
, and Karl A. von Steinheil, who built one of the first electric clocks and developed the idea of an "Earth return
" or "ground return
", had previously investigated such devices.
Daniel Drawbaugh
received for an Earth battery for electric clocks (with several improvements in the art of Earth batteries). Another early patent was obtained by Emil Jahr Method of utilizing electrical Earth currents). In 1875, James C. Bryan received for his Earth Battery. In 1885, George Dieckmann, received US patent for his Electric Earth battery. In 1898, Nathan Stubblefield
received for his electrolytic coil battery, which was a combination of an earth battery and a solenoid. (For more information see US patents 155209, 182802, 495582, 728381, 3278335, 3288648, 4153757 and 4457988.) The Earth battery, in general, generated power for early telegraph transmissions and formed part of a tuned circuit
that amplified the signalling voltage over long distances.
, buried in the ground so that the soil
acts as the electrolyte
in a voltaic cell. As such, the device acts as a non-rechargeable battery. When operated only as electrolytic devices, the devices were not continuously reliable, owing to drought condition. These devices were used by early experimenters as energy sources for telegraphy
. However, in the process of installing long telegraph wires, engineers discovered that there were electrical potential differences between most pairs of telegraph stations, resulting from natural electrical currents (called telluric current
s) flowing through the ground. Some early experimenters did recognize that these currents were, in fact, partly responsible for extending the earth batteries' high outputs and long lifetimes. Later, experimenters would utilize these currents alone and, in these systems, the plates became polarized
.
It had been long known that continuous electric currents flowed through the solid and liquid portions of the Earth, and the collection of current from an electrically conductive medium in the absence of electrochemical changes (and in the absence of a thermoelectric junction) was established by Lord Kelvin. Lord Kelvin's "sea battery" was not a chemical battery. Lord Kelvin observed that such variables as placement of the electrodes in the magnetic field and the direction of the medium's flow affected the current output of his device. Such variables do not affect battery operation. When metal plates are immersed in a liquid medium, energy can be obtained and generated, including (but not limited to) methods known via magneto-hydrodynamic generator
s. In the various experiments by Lord Kelvin, metal plates were symmetrically perpendicular to the direction of the medium's flow and were carefully placed with respect to a magnetic field which differentially deflected electrons from the flowing stream. The electrodes can be asymmetrically oriented with respect to the source of energy, though.
To obtain the natural electricity, experimenters would thrust two metal plates into the ground at a certain distance from each other in the direction of a magnetic meridian, or astronomical meridian. The stronger currents flow from south to north. This phenomenon possesses a considerable uniformity of current strength and voltage. As the Earth currents flow from south to north, electrodes are positioned, beginning in the south and ending in the north, to increase the voltage at as large a distance as possible. In many early implementations, the cost was prohibitive because of an over-reliance on extreme spacing between electrodes.
It has been found that all the common metals behave relatively similarly. The two spaced electrodes, having a load in an external circuit connected between them, are disposed in an electrical medium, and energy is imparted to the medium in such manner that "free electrons
" in the medium are excited. The free electrons then flow into one electrode to a greater degree than in the other electrode, thereby causing electric current to flow in the external circuit through the load. The current flows from that plate whose position in the electropotential series is near the negative end (such as palladium
). The current produced is highest when the two metals are most widely separated from each other in the electropotential series, and when the material nearer the positive end is to the north, while that at the negative end is towards the south. The plates, one copper and another iron or carbon, are connected above ground by means of a wire with as little resistance as possible. In such an arrangement, the electrodes are not appreciably chemically corroded, even when they are in earth saturated with water, and are connected together by a wire for a long time.
It had been found that to strengthen the current, it was most advantageous to drive the northerly electropositive electrode deeper into the medium than the southerly electrode. The greatest currents and voltages were obtained when the difference in depth was such that a line joining the two electrodes was in the direction of the magnetic dip
, or magnetic inclination. When the previous methods were combined, the current was tapped and utilized in any well-known manner.
In some cases, a pair of plates with differing electrical properties, and with suitable protective coatings, were buried below the ground. A protective or other coating covered each entire plate. A copper plate could be coated with powdered coke
, a processed carbonaceous
material. To a zinc plate, a layer of felt
could be applied. To use the natural electricity, earth batteries fed electromagnets, the load, that were part of a motor mechanism.
Electrode
An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit...
s made of two dissimilar metals, such as iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
and copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
, which are buried in the soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...
or immersed in the sea
Sea
A sea generally refers to a large body of salt water, but the term is used in other contexts as well. Most commonly, it means a large expanse of saline water connected with an ocean, and is commonly used as a synonym for ocean...
. Earth batteries act as water activated batteries
Water-activated battery
A water-activated battery is a disposable reserve battery that does not contain an electrolyte and hence produces no voltage until it is soaked in water for several minutes.-Description:...
and if the plates are sufficiently far apart, they can tap telluric currents. Earth batteries are sometimes referred to as Telluric power sources and Telluric generators.
History
One of the earliest examples of an earth battery was built by Alexander BainAlexander Bain (inventor)
Alexander Bain was a Scottish inventor and engineer who was first to invent and patent the electric clock. Bain installed the railway telegraph lines between Edinburgh and Glasgow.-Early life:...
in 1841 in order to drive a prime mover
Engine
An engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines burn a fuel to create heat which is then used to create motion...
. Bain buried plates of zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
and copper in the ground
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...
about one meter apart and used the resulting voltage, of about one volt, to operate a clock. Carl Friedrich Gauss
Carl Friedrich Gauss
Johann Carl Friedrich Gauss was a German mathematician and scientist who contributed significantly to many fields, including number theory, statistics, analysis, differential geometry, geodesy, geophysics, electrostatics, astronomy and optics.Sometimes referred to as the Princeps mathematicorum...
, who had researched Earth's magnetic field
Earth's magnetic field
Earth's magnetic field is the magnetic field that extends from the Earth's inner core to where it meets the solar wind, a stream of energetic particles emanating from the Sun...
, and Karl A. von Steinheil, who built one of the first electric clocks and developed the idea of an "Earth return
Ground (electricity)
In electrical engineering, ground or earth may be the reference point in an electrical circuit from which other voltages are measured, or a common return path for electric current, or a direct physical connection to the Earth....
" or "ground return
Ground (electricity)
In electrical engineering, ground or earth may be the reference point in an electrical circuit from which other voltages are measured, or a common return path for electric current, or a direct physical connection to the Earth....
", had previously investigated such devices.
Daniel Drawbaugh
Daniel Drawbaugh
Daniel Drawbaugh was a purported inventor of the telephone for which he sought a patent in 1880. His claims were contested by the Bell Telephone Company, which won a court decision in 1888....
received for an Earth battery for electric clocks (with several improvements in the art of Earth batteries). Another early patent was obtained by Emil Jahr Method of utilizing electrical Earth currents). In 1875, James C. Bryan received for his Earth Battery. In 1885, George Dieckmann, received US patent for his Electric Earth battery. In 1898, Nathan Stubblefield
Nathan Stubblefield
Nathan B. Stubblefield was an American inventor and Kentucky melon farmer. It has been claimed that Stubblefield invented the radio before either Nikola Tesla or Guglielmo Marconi, but his devices seem to have worked by audio frequency induction or, later, audio frequency earth conduction rather...
received for his electrolytic coil battery, which was a combination of an earth battery and a solenoid. (For more information see US patents 155209, 182802, 495582, 728381, 3278335, 3288648, 4153757 and 4457988.) The Earth battery, in general, generated power for early telegraph transmissions and formed part of a tuned circuit
Regenerative circuit
The regenerative circuit or "autodyne" allows an electronic signal to be amplified many times by the same vacuum tube or other active component such as a field effect transistor. It consists of an amplifying vacuum tube or transistor with its output connected to its input through a feedback...
that amplified the signalling voltage over long distances.
Metals and soilsPotential Differences of metals(Soil Galvanic series Galvanic series The galvanic series determines the nobility of metals and semi-metals. When two metals are submerged in an electrolyte, while electrically connected, the less noble will experience galvanic corrosion. The rate of corrosion is determined by the electrolyte and the difference in nobility... ) |
||
|---|---|---|
| Metal ... |
Potential V Voltage Voltage, otherwise known as electrical potential difference or electric tension is the difference in electric potential between two points — or the difference in electric potential energy per unit charge between two points... Cu/CuSO4 electrode Electrode An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit... |
|
| Magnesium Magnesium Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole... (pure) |
-1.75 | |
| Magnesium (alloy) | -1.60 | |
| Zinc Zinc Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2... |
-1.10 | |
| Aluminum (alloy) | -1.05 | |
| Aluminum (pure) | -0.8 22 | |
| Steel Steel Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten... (clean) |
-0.50 to -0.80 | |
| Steel (rusted) | -0.20 to -0.50 | |
| Cast Iron Cast iron Cast iron is derived from pig iron, and while it usually refers to gray iron, it also identifies a large group of ferrous alloys which solidify with a eutectic. The color of a fractured surface can be used to identify an alloy. White cast iron is named after its white surface when fractured, due... |
-0.50 | |
| Lead Lead Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed... |
-0.50 | |
| Steel (concrete) | -0.20 | |
| Copper Copper Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish... |
-0.20 | |
| Brass Brass Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin... |
-0.20 | |
| Bronze Bronze Bronze is a metal alloy consisting primarily of copper, usually with tin as the main additive. It is hard and brittle, and it was particularly significant in antiquity, so much so that the Bronze Age was named after the metal... |
-0.20 | |
| Steel (mill scale Mill scale Mill scale, often shortened to just scale, is the flaky surface of hot rolled steel, iron oxides consisting of Iron oxide, hematite, and magnetite.... ) |
-0.20 | |
| Cast iron (high silicon) | -0.20 | |
| Carbon Carbon Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds... |
+0.30 | |
| Graphite Graphite The mineral graphite is one of the allotropes of carbon. It was named by Abraham Gottlob Werner in 1789 from the Ancient Greek γράφω , "to draw/write", for its use in pencils, where it is commonly called lead . Unlike diamond , graphite is an electrical conductor, a semimetal... |
+0.30 | |
| Coke Coke (fuel) Coke is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. Cokes from coal are grey, hard, and porous. While coke can be formed naturally, the commonly used form is man-made.- History :... |
+0.30 | |
Notes:
Ref.: Engineering Tutorials: Potential of Metals in Soils |
||
Operation and use
The simplest earth batteries consist of conductive plates from different locations in the electropotential seriesGalvanic series
The galvanic series determines the nobility of metals and semi-metals. When two metals are submerged in an electrolyte, while electrically connected, the less noble will experience galvanic corrosion. The rate of corrosion is determined by the electrolyte and the difference in nobility...
, buried in the ground so that the soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...
acts as the electrolyte
Electrolyte
In chemistry, an electrolyte is any substance containing free ions that make the substance electrically conductive. The most typical electrolyte is an ionic solution, but molten electrolytes and solid electrolytes are also possible....
in a voltaic cell. As such, the device acts as a non-rechargeable battery. When operated only as electrolytic devices, the devices were not continuously reliable, owing to drought condition. These devices were used by early experimenters as energy sources for telegraphy
Telegraphy
Telegraphy is the long-distance transmission of messages via some form of signalling technology. Telegraphy requires messages to be converted to a code which is known to both sender and receiver...
. However, in the process of installing long telegraph wires, engineers discovered that there were electrical potential differences between most pairs of telegraph stations, resulting from natural electrical currents (called telluric current
Telluric current
A telluric current , or Earth current, is an electric current which moves underground or through the sea. Telluric currents result from both natural causes and human activity, and the discrete currents interact in a complex pattern...
s) flowing through the ground. Some early experimenters did recognize that these currents were, in fact, partly responsible for extending the earth batteries' high outputs and long lifetimes. Later, experimenters would utilize these currents alone and, in these systems, the plates became polarized
Polarization
Polarization is a property of certain types of waves that describes the orientation of their oscillations. Electromagnetic waves, such as light, and gravitational waves exhibit polarization; acoustic waves in a gas or liquid do not have polarization because the direction of vibration and...
.
It had been long known that continuous electric currents flowed through the solid and liquid portions of the Earth, and the collection of current from an electrically conductive medium in the absence of electrochemical changes (and in the absence of a thermoelectric junction) was established by Lord Kelvin. Lord Kelvin's "sea battery" was not a chemical battery. Lord Kelvin observed that such variables as placement of the electrodes in the magnetic field and the direction of the medium's flow affected the current output of his device. Such variables do not affect battery operation. When metal plates are immersed in a liquid medium, energy can be obtained and generated, including (but not limited to) methods known via magneto-hydrodynamic generator
MHD generator
The MHD generator or dynamo transforms thermal energy or kinetic energy directly into electricity. MHD generators are different from traditional electric generators in that they can operate at high temperatures without moving parts...
s. In the various experiments by Lord Kelvin, metal plates were symmetrically perpendicular to the direction of the medium's flow and were carefully placed with respect to a magnetic field which differentially deflected electrons from the flowing stream. The electrodes can be asymmetrically oriented with respect to the source of energy, though.
To obtain the natural electricity, experimenters would thrust two metal plates into the ground at a certain distance from each other in the direction of a magnetic meridian, or astronomical meridian. The stronger currents flow from south to north. This phenomenon possesses a considerable uniformity of current strength and voltage. As the Earth currents flow from south to north, electrodes are positioned, beginning in the south and ending in the north, to increase the voltage at as large a distance as possible. In many early implementations, the cost was prohibitive because of an over-reliance on extreme spacing between electrodes.
It has been found that all the common metals behave relatively similarly. The two spaced electrodes, having a load in an external circuit connected between them, are disposed in an electrical medium, and energy is imparted to the medium in such manner that "free electrons
Free electron model
In solid-state physics, the free electron model is a simple model for the behaviour of valence electrons in a crystal structure of a metallic solid. It was developed principally by Arnold Sommerfeld who combined the classical Drude model with quantum mechanical Fermi-Dirac statistics and hence it...
" in the medium are excited. The free electrons then flow into one electrode to a greater degree than in the other electrode, thereby causing electric current to flow in the external circuit through the load. The current flows from that plate whose position in the electropotential series is near the negative end (such as palladium
Palladium
Palladium is a chemical element with the chemical symbol Pd and an atomic number of 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired...
). The current produced is highest when the two metals are most widely separated from each other in the electropotential series, and when the material nearer the positive end is to the north, while that at the negative end is towards the south. The plates, one copper and another iron or carbon, are connected above ground by means of a wire with as little resistance as possible. In such an arrangement, the electrodes are not appreciably chemically corroded, even when they are in earth saturated with water, and are connected together by a wire for a long time.
It had been found that to strengthen the current, it was most advantageous to drive the northerly electropositive electrode deeper into the medium than the southerly electrode. The greatest currents and voltages were obtained when the difference in depth was such that a line joining the two electrodes was in the direction of the magnetic dip
Magnetic dip
Magnetic dip or magnetic inclination is the angle made by a compass needle with the horizontal at any point on the Earth's surface. Positive values of inclination indicate that the field is pointing downward, into the Earth, at the point of measurement...
, or magnetic inclination. When the previous methods were combined, the current was tapped and utilized in any well-known manner.
In some cases, a pair of plates with differing electrical properties, and with suitable protective coatings, were buried below the ground. A protective or other coating covered each entire plate. A copper plate could be coated with powdered coke
Petroleum coke
Petroleum coke is a carbonaceous solid derived from oil refinery coker units or other cracking processes. Other coke has traditionally been derived from coal....
, a processed carbonaceous
Carbonaceous
Carbonaceous is the defining attribute of a substance rich in carbon. Particularly, carbonaceous hydrocarbons are very unsaturated, high-molecular-weight hydrocarbons, having an elevated carbon:hydrogen ratio....
material. To a zinc plate, a layer of felt
Felt
Felt is a non-woven cloth that is produced by matting, condensing and pressing woollen fibres. While some types of felt are very soft, some are tough enough to form construction materials. Felt can be of any colour, and made into any shape or size....
could be applied. To use the natural electricity, earth batteries fed electromagnets, the load, that were part of a motor mechanism.
See also
- Water-activated batteryWater-activated batteryA water-activated battery is a disposable reserve battery that does not contain an electrolyte and hence produces no voltage until it is soaked in water for several minutes.-Description:...
- Soil scienceSoil scienceSoil science is the study of soil as a natural resource on the surface of the earth including soil formation, classification and mapping; physical, chemical, biological, and fertility properties of soils; and these properties in relation to the use and management of soils.Sometimes terms which...
: soil acidity & soil moisture - Soil resistance & groundingGround (electricity)In electrical engineering, ground or earth may be the reference point in an electrical circuit from which other voltages are measured, or a common return path for electric current, or a direct physical connection to the Earth....
- AntennaAntenna (radio)An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...
& ground antenna - Transmission mediumTransmission mediumA transmission medium is a material substance that can propagate energy waves...
& electromagnetic inductionElectromagnetic inductionElectromagnetic induction is the production of an electric current across a conductor moving through a magnetic field. It underlies the operation of generators, transformers, induction motors, electric motors, synchronous motors, and solenoids.... - Electric fieldElectric fieldIn physics, an electric field surrounds electrically charged particles and time-varying magnetic fields. The electric field depicts the force exerted on other electrically charged objects by the electrically charged particle the field is surrounding...
& near and far fieldNear and far fieldThe near field and far field and the transition zone are regions of the electromagnetic radiation field that emanates from a transmitting antenna, or as a result of radiation scattering off an object... - MetalMetalA metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...
, electrodeElectrodeAn electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit...
s, & contact potentialContact potentialContact potential may refer to:* Contact electrification* Galvani potential difference * Volta potential difference... - Acidity & baseBase (chemistry)For the term in genetics, see base A base in chemistry is a substance that can accept hydrogen ions or more generally, donate electron pairs. A soluble base is referred to as an alkali if it contains and releases hydroxide ions quantitatively...
s
General information
- Park Benjamin and Melvin L. Severy, The Voltaic Cell: Its Construction and Its Capacity. Wiley, 1893. 562 pages. Pages 317 - 319.
- George Milton Hopkins, Experimental Science: Elementary, Practical and Experimental Physics. Munn & Co., 1902. Pages 437 - 451.
- Frederick Collier Bakewell, Electric science, its history, phenomena and applications. 1853. Pages 182 - 184.
- James Napier, A manual of electro-metallurgy. 1876. Pages 48–49.
- William Edward Armytage Axon, The Mechanic's Friend. Trübner, 1875. 339 pages. Pages 303-304.
- Adolph A. Fesquet, Oliver Byrne, and John Percy, The Practical Metal-worker's Assistant. H.C. Baird & Co., 1878. 683 pages. Pages 529-530.
- Eugenii Katz, "Alexander Bain". The history of electrochemistry, electricity and electronics; Biosensors & Bioelectronics.
- Vassilatos, Gerry, "An Introduction to the Mysteries of Ground Radio".
- Burns, R. W., "Alexander Bain, a most ingenious and meritorious inventor". Engineering Science and Education Journal, Volume 2, Issue 2, Apr 1993. Pages 85–93. ISSN 0963-7346
- R.J.Edwards G4FGQ, Measurement of Soil Resistivity & Calculation of Earth Electrode Resistance. 15 February 1998
- The Gentleman's magazine. (1731). London: [s.n.]. Page 587.
- Spencer W. Richardson, "The Flow of Electricity through Dielectrics". Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, Vol. 92, No. 635 (Nov. 1, 1915), pp. 101–107.
- John Patterson Abernethy, The Modern Service of Commercial and Railway Telegraphy. 1887. 423 pages. Page 72.
- William Dwight, Whitney Dictionary: An Encyclopedic Lexicon of the English Language. Page 1405.
- Thomas Dixon Lockwood, Electricity, Magnetism, and Electric Telegraphy. D. Van Nostrand Co., 1883. 375 pages. Page 42.
- Edwin James Houston, A Dictionary of Electrical Words, Terms and Phrases. P.F. Collier & Son, 1903. Page 756.
- Henry Minchin , Student's Text-book of Electricity. Lockwood, 1867. 519 pages. Pages 477 - 485. (Alternative copy)
- Vassilatos, G. (2000). Lost science. Kempton, Ill: Adventures Unlimited.
- "Telluric Currents: The Natural Environment and Interactions with Man-made Systems". The Earth's Electrical Environment (1986), Commission on Physical Sciences, Mathematics, and Applications.
- Prescott, G. B. (1860). History, theory, and practice of the electric telegram. Boston: Ticknor and Fields. 468 page.
Patents
- A. Bain, " Copying surfaces by electricity".
- A. Bain, " Improvements in electric telegraphs".
- W. P. Piggot, " Telegraph cable".
- W. D. Snow, " Earth-batteries for generating electricity".
- J. Cerpaux, " Electric piles".
- Daniel Drawbaugh, " Earth battery for electric clocks".
- M. Emme, " Ground generator of electricity".
- M. Emme, " Storage Battery".
- Jahr, Emil, " Method of utilizing electrical earth currents".
- Bryan, James C., " Improvements in lightning rods".
- Bryan, James C., " Earth Battery". February 23, 1875.
- Bryan, James C., " Improvements in lightning rods".
- James M. Dices, " Immersion type battery".
- Dieckmann, George F., " Electric Earth Battery". November 3, 1885.
- Stubblefield, Nathan, " Electric battery". May 8, 1898.
- William T. Clark, " Method and apparatus for generating electricity".
- Ryeczek, " Earth battery". July 3, 1984.
Further reading
- Lamont, J. V., "Der Erdstrom und der Zusammen desselben mit dem Erdmagnetismus". Leopold-Voss-Verlag, Leipzig und Muenchen, 1862. (Tr., Telluric currents and their relationship to geomagnetism)
- Weinstein, "Electrotechnische Zeitshrift". 1898, pg., 794. (Tr., Electrotechnic magazine)
- John Timbs, The Year-book of Facts in Science and Art. 1868. Page 130.
- Journal of the Telegraph. Western Union Telegraph, Co., 1914.