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Auguste-Arthur De La Rive was a Swiss physicist, one of the founders of the electrochemical theory of batteries. He explained the rotatory movements observed at the time of the aurorae boreales by the influence of the terrestrial magnetism. Auguste-Arthur De La Rive was a Swiss physicist, one of the founders of the electrochemical theory of batteries. Father of Auguste De La Rive was the fervent freedom fighter Charles Gaspard De La Rive (1770-1834) which fled sentenced to death to Scotland, returned later, however, to Geneva and prepared there a modern lab.
Auguste De La Rive got to know the chemist Michael Faraday (1791-1867), during visit with his father, at the age of 13 years. A deep lifelong friendship arose in run of the time from this acquaintance. Guest of his father was also an Andre Marie Ampere (1775 - 1836), so Auguste De La Rive knew the famous scientific researches of his time already in his childhood.
De La Rive began experimenting with the voltaic cell (1836) and supported the idea of Michael Faraday that the electricity was the result of chemical reactions in the cell. During his scientific career he designed an electrochemical condenser (1843); studied electricity and magnetism, presented a double current theory; opposed the contact theory of electricity (contact by 2 dissimilar metals) because he insisted that the only source of electrification was chemical; studied electricity passing through gases, and demonstrated that ozone is formed by electrical sparks in pure oxygen. He invented a prize-winning electroplating method to apply gold onto brass and silver.
He determined the specific heat of various gases and examined the temperature of the Earth’s crust. De La Rive was a contemporary of Faraday, Ampere and Oersted, with whom he exchanged correspondance on electricity. He spent his life in England, France, and Switzerland. De La Rive was editor of science journals, and member of English and French scientific organizations. De La Rive also wrote a three-volume treatise on electricity, titled: “A Treatise on Electricity: In Theory and Practice", which was translated into the English language. De La Rive taught from 1823 to 1836 as a professor of physics in colleges in Geneva, London and Paris. Later he gave up his professorship and devoted himself to politics and was also active as a scientific writer.
The first attempt to make a practicable incandescent lamp was probably made by Arthur de la Rive in 1820. He used a platinum filament in a partial vacuum.
As a demonstration to explain the rotatory movements observed at the time of the aurorae boreales by the influence of the terrestrial magnetism, De La Rive assembled an apparatus using an egg-shaped evacuated glass chamber on an electromagnet. The instrument is powered by a Ruhmkorff coil and connected to a pneumatic pump, and demonstrates the rotatory effect of a magnetic field on an electric discharge in a rarefied gas. De La Rive’s electric theory stated that the aurora, being influenced by the earth’s magnetic field, would take place in the polar regions through processes of discharge between the positive electricity concentrated in the upper regions of the atmosphere and the negative electricity of the Earth. De la Rive’s theoretical hypothesis was more credible due to the observation, in that period, of a kind of rotational movement of the aurora borealis.
The instrument rests upon a solid circular mahogany base and vertically supports a magnet and an egg-shaped glass ball. In the upper part, the ball is a pair of brass taps: the one that is placed higher produces a first vacuum with a pneumatic machine; the other is used to introduce some drops of ether or of turpentine oil into the ball and then, with the pneumatic machine, to achieve an extremely rarefied vapour.
A soft iron rod is contained in the air-tight glass egg for 3/4 of its height and is connected to a polar expansion iron electromagnet at the base of the glass egg. Except for its extremities, the iron rod is entirely covered by a glass tube that is insulated by a layer of shellac. The part of the glass tube that is inside the egg is wrapped by a copper ring on the bottom and enclosed by an iron lid on top. A pair of brass rheofores, positioned halfway up the device, electrically connect the copper ring with the iron lid. A second pair of brass rheofores, on the mahogany base of the instrument, provides for the energy supply to the electro-magnet.
A beam of light is produced within the glass egg by supplying only the copper ring and the cylinder’s iron lid protecting the rod. The beam is more or less regular and is spread all around the rod, as was the case in the experiment of the electric egg. By supplying the electro-magnet as well, the phenomenon changes, and the dispersed light concentrates in only one beam of light that starts rotating slowly around the poles of the magnetised cylinder, alternating the direction of its rotation according to the direction of the induced current, is manually reversible through a Ruhmkorff commutator on the base of the instrument.
An electron discharge starts at a wire at the top of the tube and trails down to a ring at the bottom. When a cylindrical bar magnet at the center of the tube is activated by a 5-volt power supply the discharge precesses around the magnet. This demonstates the rotation of a vacuum discharge streamer under the influence of a magnetic field.
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