Michael Faraday Quotes (1791-1867)

“ALL THIS IS A DREAM. Still examine it by a few experiments. Nothing is too wonderful to be true, if it be consistent with the laws of nature; and in such things as these experiment is the best test of such consistency.”

“Mr. Gladstone, then Chancellor of the Exchequer, had interrupted him in a description of his work on electricity to put the impatient inquiry: 'But, after all, what use is it?' Like a flash of lightning came the response: 'Why, sir, there is every probability that you will soon be able to tax it!'”

“When I consider the multitude of associated forces which are diffused through nature — when I think of that calm balancing of their energies which enables those most powerful in themselves, most destructive to the world's creatures and economy, to dwell associated together and be made subservient to the wants of creation, I rise from the contemplation more than ever impressed with the wisdom, the beneficence, and grandeur, beyond our language to express, of the Great Disposer of us all.”

“I have been driven to assume for some time, especially in relation to the gases, a sort of conducting power for magnetism. Mere space is Zero. One substance being made to occupy a given portion of space will cause more lines of force to pass through that space than before, and another substance will cause less to pass. The former I now call Paramagnetic & the latter are the diamagnetic. The former need not of necessity assume a polarity of particles such as iron has with magnetic, and the latter do not assume any such polarity either direct or reverse. I do not say more to you just now because my own thoughts are only in the act of formation, but this I may say: that the atmosphere has an extraordinary magnetic constitution, & I hope & expect to find in it the cause of the annual & diurnal variations, but keep this to yourself until I have time to see what harvest will spring from my growing ideas.”

“I have been driven to assume for some time, especially in relation to the gases, a sort of conducting power for magnetism. Mere space is Zero. One substance being made to occupy a given portion of space will cause more lines of force to pass through that space than before, and another substance will cause less to pass. The former I now call Paramagnetic & the latter are the diamagnetic. The former need not of necessity assume a polarity of particles such as iron has with magnetic, and the latter do not assume any such polarity either direct or reverse. I do not say more to you just now because my own thoughts are only in the act of formation, but this I may say: that the atmosphere has an extraordinary magnetic constitution, & I hope & expect to find in it the cause of the annual & diurnal variations, but keep this to yourself until I have time to see what harvest will spring from my growing ideas.”

“Study of the conduction of electricity in liquids became possible at the beginning of the nineteenth century, following the discovery of the electrolytic cell by Volta in 1800, which provided the first continuous source of electric current. It was soon discovered that the conduction of electricity by solutions is accompanied by chemical reactions at the electrodes which serve to conduct the current into and out of the solution. Nicholson and Carlisle demonstrated the decomposition of water into hydrogen and oxygen by a current in 1801. Davy's discovery of sodium and potassium metals by electrolysis of moist soda and [caustic] potash was a striking example of the novelty of electrochemical decomposition. Many of the phenomena of electrolysis were already known when Michael Faraday began his researches. It was the quantitative relationship between electrochemical change and current which interested Faraday and enabled him to correlate the mass of experimental data that had accumulated since 1800. Faraday's laws of electrolysis, which were published in 1833, state: (1) that the amount of chemical decomposition produced by an electric current (that is, the mass of substance deposited or dissolved at an electrode) is proportional to the quantity of electricity passed. (2) that the amounts of different substances released or dissolved at electrodes by the same quantity of electricity are proportional to their chemical equivalents. From the second law, it follows that the amount of electricity required to liberate or dissolve one equivalent weight of any substance by electrolysis is constant. It was not until after Faraday's death that the significance of his laws of electrolysis for atomic theory was realized. In 1881 von Helmholtz pointed out that if elementary substances are composed of atoms, it follows from Faraday's laws of electrolysis that electricity also is composed of elementary portions which behave like atoms of electricity. Investigations on the conduction of electricity by gases led to the identification of the electron as the fundamental unit of electricity at the end of the century. Faraday's positive and negative ions are therefore atoms (or groups of atoms or radicals)) with a deficiency or an excess of an integral number of electrons, where the integral number is the valency of the atom. The ions move in opposite directions through the solution to the electrodes where their charges are neutralised, causing them to be discharged to neutral atoms or radicals. These are the primary electrode reactions, of which the deposition of silver on a platinum cathode in the silver coulometer is a typical example.”

“He was little interested mathematics or theory; for example, when his ideas on magnetic fields were extensively developed later by James Clerk Maxwell (1831-1879), Faraday was little concerned with the results. His own scientific career was characterized by simple ideas and simple experiments.”

“In 1831 his original researches began to center about the relation of electricity and magnetism. ...Even as early as 1824 he had noticed the effects of a current of electricity upon a magnet. Now he found that this electrical action could be increased if the wire carrying the current was made into a coil. From that point he went on to study the push or pulling action of the coil upon the magnet, the effect of having a coil of more turns, and a way by which the coil and magnet, if free to move, could be made to move around each other. He was working out the principles that operate in today's electric motors. By 1831 he had reversed the problem... He had shown that the mere motion of the magnet within a closed-end coil was enough to set moving through the coil a small current that had not been there before. He called this new current an "induced" one and proceeded to study how the current could be increased in its quantity and intensity. The experimental results were revolutionary. The principles of induction discovered by Faraday are used today in telephones, induction coils, electric generators, transformers, the motors of electric clocks, and dozens of other pieces of electrical equipment.”

“As a philosopher, his first great characteristic was the trust which he put in facts. He said of himself, "In early life I was a very lively imaginative person, who could believe in the Arabian Nights as easily as in the Encyclopedia, but facts were important to me, and saved me. I could trust a fact." Over and over again he showed his love of experiments in his writings and lectures: "Without experiment I am nothing." "But still try, for who knows what is possible?" "All our theories are fixed upon uncertain data, and all of them want alteration and support from facts." "One thing, however, is fortunate, which is, that whatever our opinions, they do not alter nor derange the laws of nature." His second great characteristic was his imagination. It rose sometimes to divination, or scientific second sight, and led him to anticipate results that he or others afterwards proved to be true.”

“I have been favoured by a sight of the forthcoming series of Dr. Faraday's admirable "Researches;" in which that assiduous and successful philosopher labours to prove by experiment that electrical induction is transmitted to distant bodies by intervening matter.”

“His health [was] probably affected by mercury poisoning. This was a then unrealized health hazard that undoubtedly affected many nineteenth-century scientists who worked in the laboratory, where spilled mercury often accumulated between and beneath floorboards and generated a permanent atmosphere of mercury vapor.”

“Gradually... during the second half of the nineteenth century, the uncomfortable feeling of dislike of the action at a distance, which had been so strong in Huygens and other contemporaries of Newton, but had subsided during the eighteenth century, began to emerge again, and gained strength rapidly. This was favoured by the purely mathematical transformation (which can be compared in a sense with that from the Ptolemaic to the Copernican system), replacing Newton's finite equations by the differential equations, the potential becoming the primary concept, instead of the force, which is only the gradient of the potential. These ideas, of course, arose first in the theory of electricity and magnetism or perhaps one should say in the brain of Faraday.”

“A point highly illustrative of the character of Faraday now comes into view. He gave an account of his discovery of Magneto-electricity in a letter to his friend M. Hachette, of Paris, who communicated the letter to the Academy of Sciences. The letter was translated and published ; and immediately afterwards two distinguished Italian philosophers took up the subject, made numerous experiments, and published their results before the complete memoirs of Faraday had met the public eye. This evidently irritated him. He reprinted the paper of the learned Italians in the Philosophical Magazine accompanied by sharp critical notes from himself. He also wrote a letter dated Dec. 1,1832, to Gay Lussac, who was then one of the editors of the Annales de Chimie in which he analysed the results of the Italian philosophers, pointing out their errors, and' defending himself from what he regarded as imputations on his character. The style of this letter is unexceptionable, for Faraday could not write otherwise than as a gentleman; but the letter shows that had he willed it he could have hit hard. We have heard much of Faraday's gentleness and sweetness and tenderness. It is all true, but it is very incomplete. You cannot resolve a powerful nature into these elements, and Faraday's character would have been less admirable than it was had it not embraced forces and tendencies to which the silky adjectives "gentle" and "tender" would by no means apply. Underneath his sweetness and gentleness was the heat of a volcano. He was a man of excitable and fiery nature; but through high self-discipline he had converted the fire into a central glow and motive power of life, instead of permitting it to waste itself in useless passion. "He that is slow to anger" saith the sage, "is greater than the mighty, and he that ruleth his own spirit than he that taketh a city." Faraday was not slow to anger, but he completely ruled his own spirit, and thus, though he took no cities, he captivated all hearts.”

“The conception of lines of force was introduced by Faraday to form a mental picture of the processes going on in the electric field. To him these lines were not mere mathematical abstractions. He ascribed to them properties that gave them a real physical significance. They terminate on opposite charges, are always in a state of tension, tending to shorten themselves, and are mutually repellent. The direction of a line of force at any point gives the direction of the field at that point. With the help of these properties of lines of force it is possible to obtain an idea of the distribution of the intensity of the field surrounding electrically charged bodies. The idea of tubes of force has been introduced to make the method of Faraday metrical rather than merely descriptive. A tube of force is obtained by drawing a number of lines of force through the boundary of any small closed curve. The lines then form a tubular surface, which, it can be proved, will never be cut by any lines of force, and the extremities of which enclose equal and opposite charges. By properly choosing the area of the surface enclosed by the curve through which the lines are drawn the extremities of the tube can be made to enclose unit charge. Such a unit tube is called a Faraday tube. Maxwell and J. J. Thomson have made an exhaustive study of these tubes of force and expressed their properties in mathematical terms. The result that interests us here is that a tube of force behaves as though it had inertia, so that in order to move a tube work must be done. This explains why a charge behaves as if it had mass. It must be remarked that the conception of tubes of forces is used here merely to aid in understanding the phenomena. Whether or not tubes of force, or even the ether, possess any physical significance is a question. Modern developments seem to indicate that this question must be answered in the negative.”