Page:Experimental researches in chemistry and.djvu/491

476 fact, namely, whether the effect was as reported; but how many were unable to do this? They were sure they could keep their hands immovable,—were sure they could do so whilst watching the result,—were sure that accordance of swing with an expected direction was not the result of their desires or involuntary motions. How easily all these 'points could be put to the proof by not looking at the objects, yet how difficult for the experimenter to deny himself that privilege! I have rarely found one who would freely permit the substance experimented with to be screened from his sight, and then have its position changed.

When engaged in the investigation of table-turning, I constructed a very simple apparatus, serving as an index, to show the unconscious motions of the hand upon the table. The results were either that the index moved before the table, or that neither index nor table moved; and in numerous cases all moving power was annihilated. A universal objection was made to it by the table-turners;—it was said to paralyse the powers of the mind. But the experimenters need not see the index; they may leave their friends to watch that, and their minds may revel in any power that their expectation or their imagination can confer. So restrained, however, a dislike to the trial arises; but what is that except a proof, that whilst they trust themselves they doubt themselves, and are not willing to proceed to the decision, lest the trust which they like should fail them, and the doubt which they dislike rise to the authority of truth?

Again, in respect of the action of magnets on the body, it is almost impossible for an uninstructed person to enter profitably upon such an inquiry. He may observe any symptom which his expectation has been accidentally directed to:—yet be unconscious of any, if unaware of his subjection to the magnetic force, or of the conditions and manner of its application.

As a proof of the extent of this influence, even on the minds of those well-aware of its power, and desirous under every circumstance to escape from it, I will mention the practice of the chemist; who, dealing with the balance, that impartial decider which never fails in its indication, but offers its evidence with all simplicity, durability, and truth, still remembers