Extracts from Professor Faraday's Letter on Table Moving.
Athenæum, July 2, 1853, p. 801.
"The object which I had in view in my inquiry was, not to satisfy myself, for my conclusion had been formed already on the evidence of those who had turned tables,—but that I might be enabled to give a strong opinion, founded on facts, to the many who applied to me for it. Yet the proof which I sought for, and the method followed in the inquiry, were precisely of the same nature as those which I should adopt in any other physical investigation. The parties with whom I have worked were very honourable, very clear in their intentions, successful table-movers, very desirous of succeeding in establishing the existence of a peculiar power, thoroughly candid, and very effectual. It is with me a clear point that the table moves when the parties, though they strongly wish it, do not intend, and do not believe, that they move it by ordinary mechanical power. They say, the table draws their hands; that it moves first, and they have to follow it; that sometimes it even moves from under their hands. With some, the table will move to the right or left, according as they wish or will it; with others, the direction of the first move is uncertain;—but all agree that the table moves the hands, and not the hands the table. Though I believe the parties do not intend to move the table, but obtain the result by a quasi-involuntary action, still I had no doubt of the influence of expectation upon their minds, and, through that, upon the success or failure of their efforts.
"The first point, therefore, was to remove all objections due to expectation—having relation to the substances which I might desire to use; so, plates of the most different bodies, electrically speaking, namely, sand-paper, mill-board, glue, glass, moist clay, tinfoil, card-board, gutta percha, vulcanized rubber, wood, &c., were made into a bundle, and placed on a table, under the hands of a turner. The table turned. Other bundles of other plates were submitted to different persons at other times,—and the tables turned. Henceforth, therefore, these substances may be used in the construction of apparatus. Neither during their use, nor at any other times, could the slightest trace of electrical or magnetic effects be obtained. At the same trials, it was readily ascertained that one person could produce the effect; and that the motion was not necessarily circular, but might be in a straight line. No form of experiment or mode of observation that I could devise gave me the slightest indication of any peculiar natural force. No attraction or repulsion, or signs of tangential power appeared; nor anything which could be referred to other than the mere mechanical pressure exerted inadvertently by the turner. I therefore proceeded to analyze this pressure, or that part of it exerted in a horizontal direction; doing so, in the first instance, unawares to the party. A soft cement, consisting of wax and turpentine, or wax and pomatum, was prepared. Four or five pieces of smooth slippery card-board were attached one over the other by little pellets of the cement, and the lower of these to a piece of sand-paper resting on the table; the edges of these sheets overlapped slightly, and on the under surface a pencil line was drawn over the laps, so as to indicate position. The upper card-board was larger than the rest, so as to cover the whole from sight. Then the table-turner placed the hands upon the upper card, and we waited for the result. Now, the cement was strong enough to offer considerable resistence to mechanical motion, and also to retain the cards in any new position which they might acquire, and yet weak enough to give way slowly to a continued force.
"When at last the tables, cards, and hands, all moved to the left together, and so a true result was obtained, I took up the pack. On examination, it was easy to see by the displacement of the parts of the line, that the hand had moved further than the table, and that the latter had lagged behind;—that the hand, in fact, had pushed the upper card to the left, and that the under cards and the table had followed and been dragged by it. In other similar cases, when the table had not moved, still the upper card was found to have moved, showing that the hand had carried it in the expected direction. It was evident, therefore, that the table had not drawn the hand and person round, nor had it moved simultaneously with the hand. The hand had left all things under it, behind, and the table evidently tended continually to keep the hand back.
"The next step was, to arrange an index, which should show whether the table moved first, or the hand moved before the table, or both moved or remained at rest together.... Two thin boards, nine and a-half by seven inches, were provided; a board, nine by five inches, was glued to the middle of the under side of one of these (to be called the table-board), so as to raise the edges free from the table; being placed on the table, near and parallel to its side, an upright pin was fixed close to the further edge of the board, at the middle, to serve as the fulcrum for the indicating lever. Then, four glass rods, seven inches long, and a quarter of an inch in diameter, were placed as rollers on different parts of this table-board, and the upper board placed on them; the rods permitted any required amount of pressure on the boards, with a free motion of the upper on the lower to the right and left. At the part corresponding to the pin in the lower board, a piece was cut out of the upper board, and a pin attached there, which, being bent downwards, entered the hole in the end of the short arm of the index lever: this part of the lever was of card-board: the indicating prolongation was a straight hay-stalk fifteen inches long. In order to restrain the motion of the upper board on the lower, two vulcanized rubber rings were passed round both, at the parts not resting on the table: these, whilst they tied the boards together, acted also as springs—and whilst they allowed the first, feeblest tendency to motion to be seen by the index, exerted, before the upper board had moved a quarter of an inch, sufficient power in pulling the upper board back from either side, to resist a strong lateral action of the hand.
"All being thus arranged, except that the lever was away, the two boards were tied together with string running parallel to the vulcanised rubber springs, so as to be immoveable in relation to each other. They were then placed on the table, and a table-turner sat down to them. The table very shortly moved in due order, showing that the apparatus offered no impediment to the action. A like apparatus, with metal rollers, produced the same result under the hands of another person. The index was now put into its place, and the string loosened, so that the springs should come into play. It was soon seen with the party that could will the motion in either direction (from whom the index was purposely hidden), that the hands were gradually creeping up in the direction before agreed upon, though the party certainly thought they were pressing downwards only. When shown that it was so, they were truly surprised; but when they lifted up their hands and immediately saw the index return to its normal position, they were convinced. When they looked at the index, and could see for themselves whether they were pressing truly downwards, or obliquely, so as to produce a resultant in the right or left handed direction, then such an effect never took place. Several tried, for a long while together, and with the best will in the world, but no motion, right or left, of the table or hand, or anything else, occurred.
"I think the apparatus I have described may be useful to many who really wish to know the truth of nature, and who would prefer that truth to a mistaken conclusion, desired perhaps only because it seems to be new or strange. Persons do not know how difficult it is to press directly downward, or in any given direction against a fixed obstacle, or even to know only whether they are doing so or not, unless they have some indicator which, by visible motion or otherwise, shall instruct them; and this is more especially the case when the muscles of the fingers and hand have been cramped and rendered either tingling or insensible or cold by long-continued pressure. If a finger be pressed constantly into the corner of a window-frame for ten minutes or more, and then, continuing the pressure, the mind be directed to judge whether the force at a given moment is all horizontal or all downwards, or how much is in one direction and how much in the other, it will find great difficulty in deciding, and will, at last, become altogether uncertain,—at least such is my case. I know that a similar result occurs with others, for I have had two boards arranged, separated, not by rollers, but by plugs of vulcanized rubber; and with the vertical index, when a person with his hands on the upper board is requested to press only downwards, and the index is hidden from his sight, it moves to the right, to the left, to him and from him, and in all horizontal directions; so utterly unable is he strictly to fulfil his intention without a visible and correcting indicator. Now, such is the use of the instrument with the horizontal index and rollers; the mind is instructed and the involuntary or quasi-involuntary motion is checked in the commencement, and, therefore, never rises up to the degree needful to move the table, or even permanently the index itself. No one can suppose that looking at the index can in any way interfere with the transfer of electricity, or any other power, from the hand to the board under it, or to the table. If the board tends to move, it may do so; the index does not confine it; and if the table tends to move, there is no reason why it should not. If both were influenced by any power to move together, they may do so, as they did, indeed, when the apparatus was tied, and the mind and muscles left unwatched and unchecked."
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