experiments at a distance is a matter of good augury for the future. It is much to be desired that investigators should give attention to obtaining more results in this branch of the inquiry. For independently of the fact that results of the kind form an indispensable link between instances of thought-transference at close quarters and the more striking spontaneous cases at a distance, it is important to observe that in experiments of the kind described in the present chapter the gravest objection which is at present urged, and may fairly continue to be urged, against most experiments at close quarters--viz., the risk of unconscious apprehension through normal channels--is no longer applicable. Moreover, the results can only be attributed to fraud on the extreme assumption that both parties to the experiment are implicated in deliberate and systematic collusion. _Induction of Sleep at a distance._ Some of the most striking experimental cases, which are concerned with the production of hallucinations, are reserved for later discussion. (See Chapter X.) But perhaps the most valuable body of testimony for the agency of thought-transference at a distance is to be found in the experiments recorded by French observers in the induction of sleep. It is not a little remarkable that this, one of its rarest and most striking manifestations, should have been among the first and, until recently, almost the only form of telepathy which attracted attention amongst French investigators. Moreover, of late years at any rate, this particular form of experiment has rarely succeeded except in France, and with hypnotic subjects. But as the number of physicians who practise hypnotism increases in other countries, we may no doubt hope to see the observations already made confirmed and enlarged. The analogy of the experiments in the induction of anæsthesia by thought-transference, recorded in the last chapter, would perhaps have prepared us to accept the induction of sleep as a not improbable effect of telepathy. But we are not without more direct testimony. The opening sentences of Professor Janet's account of the experiment with Madame B. show us that, in this case at all events, the conscious will of the operator was necessary to produce the hypnotic trance, even at close quarters. When, therefore, we find that the same cause, operating at a distance, is constantly followed by a like effect, there can be no reasonable ground for refusing to recognise the operator's will as in this case also the cause of the sleep; unless, indeed, we are prepared to attribute all the results to chance. No. 29.--Experiments by MM. GIBERT and JANET.