But, of course, the most satisfactory condition was that only the members of the investigating Committee should act as agents, so that signals could not possibly be given unless by one of them. This condition clearly makes it idle to represent the means by which the transferences took place as simply a trick which the members of the investigating Committee failed to detect. The trick, if trick there was, must have been one in which they, or one of them, actively shared; the only alternative to collusion on their part being some piece of carelessness amounting almost to idiocy—such as uttering the required word aloud, or leaving the selected card exposed on the table. The following series of experiments was made on April 13th, 1882. The agents were Mr. Myers and the present writer, and two ladies of their acquaintance, the Misses Mason, of Morton Hall, Retford, who had become interested in the subject by the remarkable successes which one of them had obtained in experimenting among friends.1 As neither of these ladies had ever seen any member of the Creery family till just before the experiments began, they had no opportunities for arranging a code of signals with the children; so that any hypothesis of collusion must in this case be confined to Mr. Myers or the present writer. As regards the hypothesis of want of intelligence, the degree of intelligent behaviour required of each of the four agents was simply this: (1) To keep silence on a particular subject; and (2) to avoid unconsciously displaying a particular card or piece of paper to a person situated at some yards’ distance. The first condition was realised by keeping silence altogether; the second by remaining quite still. The four observers were perfectly satisfied that the children had no means at any moment of seeing, either directly or by reflection, the selected card or the name of the selected object. The following is the list of trials:—
Objects to be named. (These objects had been brought, and still remained, in the pocket of one of the visitors. The name of the object selected for trial was secretly written down, not spoken.)
A White Penknife.—Correctly named, with the colour, the first trial.
Box of Almonds.—Correctly named.
Threepenny piece.—Failed.
Box of Chocolate.—Button-box said; no second trial given.
(A penknife was then hidden; but the place was not discovered.)
Numbers to be named.
Five.—Rightly given on the first trial.
Fourteen.—Failed.
Thirty-three.—54 (No). 34 (No). 33 (Right).
Sixty-eight.—58 (No). 57 (No). 78 (No).
Fictitious names to be guessed.
Martha Billings.—“Biggis” was said.
Catherine Smith.—“Catherine Shaw” was said.
Henry Cowper.—Failed.
Cards to be named.
Two of clubs.—Right first time.
Queen of diamonds.—Right first time.
Four of spades.—Failed.
Four of hearts.—Right first time.
King of hearts.—Right first time.
Two of diamonds.—Right first time.
Ace of hearts.—Right first time.
Nine of spades.—Right first time.
Five of diamonds.—Four of diamonds (No). Four of hearts (No). Five of diamonds (Right).
Two of spades.—Right first time.
Eight of diamonds.—Ace of diamonds said; no second trial given.
Three of hearts.—Right first time.
Five of clubs.—Failed.
Ace of spades.—Failed.
The chances against accidental success in the case of any one card are, of course, 51 to 1; yet out of fourteen successive trials nine were successful at the first guess, and only three trials can be said to have been complete failures. The odds against the occurrence of the five successes running, in the card series, are considerably over 1,000,000 to 1. On none of these occasions was it even remotely possible for the child to obtain by any ordinary means a knowledge of the object selected. Our own facial expression was the only index open to her; and even if we had not purposely looked as neutral as possible, it is difficult to imagine how we could have unconsciously carried, say, the two of diamonds written on our foreheads.
During the ensuing year, the Committee, consisting of Professor Barrett, Mr. Myers, and the present writer, made a number of experiments under similar conditions, which excluded contact and movement, and which confined the knowledge of the selected object—and, therefore, the chance of collusion with the percipient—to their own group. In some of these trials, conducted at Cambridge, Mrs. F. W. H. Myers and Miss Mason also took part. In a long series conducted at Dublin, Professor Barrett was alone with the percipient. Altogether these scrupulously guarded trials amounted to 497; and of this number 95 were completely successful at the first guess, and 45 at the second. The results may be clearer if arranged in a tabular form.
TABLE SHOWING THE SUCCESS OBTAINED WHEN THE SELECTED OBJECT WAS KNOWN TO ONE OR MORE OF THE INVESTIGATING COMMITTEE ONLY.
* A full pack was used, from which a card was in each case drawn at random.
† This number is obtained by multiplying each figure of the third column by the corresponding figure in the fourth column (e.g., 216 x 1/62), and adding the products.
‡ This entry is calculated from the first three totals in the last horizontal row, in the same way that each other entry in the last column is calculated from the first three totals in the corresponding horizontal row.
Mr. F. Y. Edgeworth, to whom these results were submitted, and who calculated the final column of the Table, has kindly appended the following remarks:—
“These observations constitute a chain or rather coil of evidence, which at first sight and upon a general view is seen to be very strong, but of which the full strength cannot be appreciated until the concatenation of the parts is considered.
“Viewed as a whole the Table presents the following data. There are in all 497 trials. Out of these there are 95 successes at the first guess. The number of successes most probable on the hypothesis of mere chance is 27. The problem is one of the class which I have discussed in the Proceedings of the S. P. R., Vol. III., p. 190, &c. The approximative formula there given is not well suited to the present case,1 in which the number of successes