Faraday to Richard Phillips   29 November 1831

Brighton | Nov 29th. 1831

Dear Phillips

For once in my life I am able to sit down and write to you without feeling that my time is so little that my letter must of necessity be a short one and accordingly I have taken an extra large sheet of paper intending to fill it with news and yet as to news I have none for I withdraw more and more from Society and all I have to say is about myself[.] But how are you getting on? are you comfortable? and how does Mrs. Phillips do; and the girls[.] Bad correspondent as I am I think you owe me a Letter and as in the course of half an hour you will be doubly in my debt pray write us and let us know all about you[.] Mrs. Faraday wishes me not to forget to put her kind remembrances to you and Mrs. Phillips in my letter[.]

Tomorrow is St Andrews day¹ but we shall be here until Thursday. I have made arrangements to be out of the Council and care little for the rest although I should as a matter of curiosity have liked to see the Duke in the Chair on such an occasion².

We are here to refresh. I have been working and writing a paper & that always knocks me up in health but now I feel well again and able to pursue my subject and now I will tell you what it is about. The title will be I think Experimental Researches in Electricity - <sect>I On the induction of electric currents <sect>II. On the evolution of Electricity from magnetism - <sect>III On a New electrical condition of matter - <sect>IV On Arago’s magnetic phenomena ³[.] There is a bill of fare for you and what is more I hope it will not disappoint you. Now the pith of all this I must give you very briefly the demonstrations you shall have in the paper when printed.

<sect>I. When an electric current is passed through one of two parallel wires it causes at first a current in the same direction through the other but this induced current does not last a moment notwithstanding the inducing current (from the Voltaic battery) is continued all seems unchanged except that the principal current continues its course but when this current is stopped then a return current occurs in the wire under induction of about the same intensity and momentary duration but in the opposite direction to that first formed[.] Electricity in currents therefore exerts an inductive action like ordinary electricity but subject to peculiar laws: the effects are a current in the same direction when the induction is established a reverse current when the induction ceases and a peculiar state in the interim[.] Common electricity probably does the same thing but as it is at present impossible to separate the beginning & the end of a spark or discharge from each other all the effects are simultaneous & neutralise each other - <sect>II. Then I found that magnets would induce just like voltaic currents and by bringing helices & wires & jackets up to the poles of magnets electrical currents were produced in them these currents being able to deflect the galvanometer or to make by means of the helix magnetic needles or in one case even to give a spark[.] Hence the evolution of electricity from magnetism. The currents were not permanent they ceased the moment the wires ceased to approach the magnet because the new & apparently quiescent state was assumed just as in the case of the induction of current[.] But when the magnet was removed & its induction therefore ceased the return currents happened as before[.] These two kinds of induction I have distinguished by the terms Volta-electric and Magneto-electric induction. Their identity of action & results is I think a very powerful proof of the truth of M. Ampere’s theory of magnetism[.]

<sect>III. The new electrical condition which intervenes by induction between the beginning & end of the inducing current gives rise to some very curious results. It explains why chemical action or other results of electricity have never been as yet obtained in trials with the magnet in fact the currents have no sensible duration. I believe it will explain perfectly the transference of elements between the poles of the pile in decomposition but this part of the subject I have reserved until the present expts are completed and it is so analogous in some of its effect to those of Ritters⁴ secondary piles⁵, De la Rive and Van Beeks⁶ peculiar properties of the poles of a voltaic pile⁷ that I should not wonder if they all proved ultimately to depend on this state. This condition of the matter I have dignified by the term Electro-tonic[.] The Electro-tonic state[.] What do you think of that; am I not a bold man, ignorant as I am, to coin words, but I have consulted the scholars⁸ - and now for <sect>IV. The new state has enabled me to make out and explain all Arago’s phenomena of the rotating magnet or copper plate⁹ I believe perfectly: but as great names are concerned, Arago, Babbage, Herschell &c.¹⁰, and as I have to differ from them, I have spoken with that modesty which you so well know you and I and John Frost¹¹ have in common and for which the world so justly commends us. I am even half afraid to tell you what it is. You will think I am hoaxing you or else in your compassion you may conclude I am deceiving myself. However you need do neither but had better laugh as I did most heartily when I found that it was neither attraction nor repulsion but just one of my old rotations in a new form[.] I cannot explain to you all the actions which are very curious but in consequence of the electro-tonic state being assumed and lost as the parts of the plate whirl under the pole and in consequence of magneto electric induction currents of electricity are formed in the direction of the radii continuing for very simple reasons as long as the motion continues but ceasing when that ceases. Hence the wonder is explained that the metal has powers on the magnet when moving but not when at rest. Hence is also explained the effect which Arago observed & which made him contradict Babbage & Herschell & say the power was repulsive but as a whole it is really tangential[.] It is quite comfortable to me to find that experiment need not quail before mathematics but is quite competent to rival it in discovery and I am amused to find that what high mathematicians have announced as the essential condition to the rotation namely that time is required has so little foundation that if the time could by possibility be anticipated instead of being required i.e. if the currents could be formed before the magnet came over the place instead of after the effect would equally ensue[.] Adieu, dear Phillips[.]

Excuse this egotistical letter from Yours Very Faithfully | M. Faraday

Address: Richard Phillips Esq | Dartmouth Street | Birmingham