Instances had already been recorded of cases where a halogen element replaced hydrogen with the production of a closely allied substance: Gay Lussac had prepared cyanogen chloride from hydrocyanic acid; Faraday, hexachlorethane from ethylene dichloride, &c. Here the electronegative halogens exercised a function similar to electro-positive hydrogen.
The quantitative precipitation of metals by the electric current, although known to Michael Faraday, was not applied to analytical chemistry until O.
The first exact quantitative study of electrolytic phenomena was made about 1830 by Michael Faraday (Experimental Researches, 1833).
Acting on this view, Faraday set himself to examine the relation between the flow of electricity round the circuit and the amount of chemical decomposition.
Faraday found that the mass of substance liberated at the electrodes in the cell C was equal to the sum of the masses liberated in the cells A and B.
Faraday examined also the electrolysis of certain fused salts such as lead chloride and silver chloride.
The opposite parts of an electrolyte, which work their way through the liquid under the action of the electric forces, were named by Faraday the ions - the travellers.
- Michael Faraday, Experimental Researches in Electricity (London, 1844 and 1855); W.
This experiment suggested to Faraday the conception of ' r,?
But it was discovered by Faraday in 1845 that all substances, including even gases, are either attracted or repelled by a sufficiently powerful magnetic pole.
4 Faraday, Exp. Res.
Faraday, Exp. Res.
Now iron, nickel and cobalt all lose their magnetic quality when heated above certain critical temperatures which vary greatly for the three metals, and it was suspected by Faraday 3 as early as 1845 that manganese might really be a ferromagnetic metal having a critical temperature much below the ordinary temperature of the air.
The best modern determinations of the value of K for gaseous oxygen agree very fairly well with that given by Faraday in 18J3 (Exp. Res.
Throughout his researches Faraday paid special regard to the medium as the true seat of magnetic action, being to a large extent guided by his pregnant conception of " lines of force," or of induction, which he considered to be " closed curves passing in one part of the course through, the magnet to which they belong, and in the other part through space," always tending to shorten themselves, and repelling one another when they were side by side (Exp. Res.
He failed in both respects, and when Michael Faraday, who overheard a portion of his conversation with Davy on the subject, was subsequently more successful, he was inclined to assert the merit of priority, to which Faraday did not admit his claim.
BENZENE, C 6 H 6, a hydrocarbon discovered in 1825 by Faraday in the liquid produced in the compression of the illuminating gas obtained by distilling certain oils and fats.
In 1868 he succeeded Faraday as Fullerian professor of chemistry at the Royal Institution, and in 1872 he was elected, in succession to Sir Benjamin Brodie, Waynflete professor of chemistry at Oxford, a chair he occupied for 40 years.
Von Hofmann, which is the Faraday lecture delivered before the London Chemical Society in March 1875, and is reprinted in Hofmann's Zur Erinnerung an vorangegangene Freunde; also W.
The work of Benjamin Franklin, Henry Cavendish, Michael Faraday and J.
Faraday introduced the important and useful conception of lines and tubes of electric force.
Faraday expressed this fact by saying that no absolute electric charge could be given to matter.
Cavendish and subsequently Faraday discovered this fact, and the latter gave the name " specific inductive capacity," or " dielectric constant," to that quality of an insulator which determines the charge taken by a conductor embedded in it when charged to a given potential.
Faraday applied it to the preparation of extremely thin films of the metal.
Faraday was first able to liquefy ammonia.
This description, quoted from James Clerk Maxwell's article in the 9th edition of the Encyclopaedia Britannica, represents the historical position of the subject up till about 1860, when Maxwell began those constructive speculations in electrical theory, based on the influence of the physical views of Faraday and Lord Kelvin, which have in their subsequent development largely transformed theoretical physics into the science of the aether.
A train of ideas which strongly impressed itself on Clerk Maxwell's mind, in the early stages of his theoretical views, was put forward by Lord Kelvin in 1858; he showed that the special characteristics of the rotation of the plane of polarization, discovered by Faraday in light propagated along a magnetic field, viz.
Hence many of his investigations were first described by Faraday in his Friday evening discourses at the Royal Institution.
Churches of this order were founded in Paisley, Glasgow, Edinburgh, Leith, Arbroath, Montrose, Aberdeen, Dunkeld, Cupar, Galashiels, Liverpool and London, where Michael Faraday was long an elder.
MICHAEL FARADAY (1791-1867), English chemist and physicist, was born at Newington, Surrey, on the 22nd of September 1791.
Faraday himself became apprenticed to a bookbinder.
Faraday took notes of these lectures, and afterwards wrote them out in a fuller form.
A specimen of one of these heavy glasses afterwards became historically important as the substance in which Faraday detected the rotation of the plane of polarization of light when the glass was placed in the magnetic field, and also as the substance which was first repelled by the poles of the magnet.
Faraday was not there at the time, but coming in afterwards he heard the conversation on the expected rotation of the wire.
In July, August and September of that year Faraday, at the request of R.
This first success of Faraday in electro-magnetic research became the occasion of the most painful, though unfounded, imputations against his honour.
Into these we shall not enter, referring the reader to the Life of Faraday, by Dr Bence Jones.
During his first period of discovery, besides the induction of electric currents, Faraday established the identity of the electrification produced in different ways; the law of the definite electrolytic action of the current; and the fact, upon which he laid great stress, that every unit of positive electrification is related in a definite manner to a unit of negative electrification, so that it is impossible to produce what Faraday called "an absolute charge of electricity" of one kind not related to an equal charge of the opposite kind.
Faraday had for a long time kept in view the possibility of using a ray of polarized light as a means of investigating the condition of transparent bodies when acted on by electric and magnetic forces.
At last, in 1845, Faraday attacked the old problem, but this time with complete success.
On the 3rd of November a new horseshoe magnet came home, and Faraday immediately began to experiment on the action in the polarized ray through gases, but with no effect.
The parents of Faraday belonged to the very small and isolated Christian sect which is commonly called after Robert Sandeman.
Faraday himself attended the meetings from childhood; at the age of thirty he made public profession of his faith, and during two different periods he discharged the office of elder.
Faraday gives the following note as to this lecture: "These observations were delivered as a lecture before His Royal Highness the Prince Consort and the members of the Royal Institution on the 6th of May 1854.
Faraday as a Discoverer, by John Tyndall (Longmans, 1st ed.
1870); The Life and Letters of Faraday, by Dr Bence Jones, secretary of the Royal Institution, in 2 vols.
(Longmans, 1870); Michael Faraday, by J.
He also carried out many experiments in magneto-optics, and succeeded in showing, what Faraday had failed to detect, the rotation under the influence of magnetic force of the plane of polarization in certain gases and vapours.
Faraday, Ann., 18 45, 56, p. 158).
The investigation of Carpenter on unconscious cerebration and of Faraday on unconscious muscular action showed early in the movement that it was not necessary to look outside the medium's own personality for the explanation of even intelligent communications unconsciously conveyed through table-tilting, automatic writing and trance-speaking - provided the matter communicated was not beyond the range of the medium's own knowledge or powers.
His great object, as it was also the great object of Faraday, was to overturn the idea of action at a distance.
He was a most prolific writer, 364 papers appearing under his name in the Royal Society's Catalogue, and he carried on a large correspondence with other men of science, such as Berzelius, Faraday, Liebig and Wohler.
Hydrochloric acid was carefully investigated at about this time by Davy, Faraday and Gay Lussac, its composition and the elementary nature of chlorine being thereby established.
Faraday, Experimental Researches in Electricity, 3 vols.
Henry Cavendish had before 1773 discovered that glass, wax, rosin and shellac have higher specific inductive capacities than air, and had actually determined the numerical ratios of these capacities, but this was unknown both to Faraday and to all other electricians of his time, since Cavendish's Electrical Researches remained unpublished till 1879.
(Macmillan, 1872); Michael Faraday; his Life and Work, by S.
In the following May he was chosen professor of natural philosophy at the Royal Institution, a post which exactly suited his striking gifts and made him a colleague of Faraday, whom in 1866 he succeeded as scientific adviser to the Trinity House and Board of Trade, and in 1867 as superintendent of the Royal Institution.
His reverent attachment to Faraday is beautifully manifested in his memorial volume called Faraday as a Discoverer (1868).