No two centres can be in fullest functional activity at the same time. For instance, if a certain centre A is alone excited, it will dominate consciousness until the centre of gravity is changed by the arrival of neurokymes at B. Attention will then be deflected from A to B. This is the explanation of delusions and hallucinations, Forel thinks, and to illustrate this point he takes the case of a person awaiting a visitor. A noise on the stairs is interpreted as the footsteps of the looked-for guest. Expectation has so strengthened the stored memory impression that the new sounds are assimilated and given the accustomed place in consciousness - i.e., the footsteps of the expected visitor.

The phenomena of hypnotism are, therefore, I take it, according to Forel, due to directed attention and psychical inhibition and dynamo-genesis, which physiologically depend on altered local cortical blood-supply and nutrition.

Forel is an uncompromising opponent of occultism, and even telepathy is to him unproved and inadmissible.

Other observers consider that there is a condition of cramp of the arterioles of the brain; and all are agreed that delicate modifications in the cerebral circulation constitute the basis of the hypnotic phenomena. We have probably no drug which acts exactly in the same way as hypnotism; otherwise we might use it as a vehicle for suggestion, especially in the case of patients who are insensible to the hypnotic influence. Cannabis indica presents certain analogous symptoms, * and apparently exposes its consumer to exaggerated susceptibility to suggestion. But there is this important difference. In hashish intoxication the suggestion is simply a natural sensory impression, received spontaneously, and greatly exaggerated. The hashish-taker sees a small sheet of water, and in his drug-induced dreams it becomes a magnificent river, a vast lake, or boundless ocean. He hears an Italian organ beneath his windows, and imagines himself listening to the orchestra at Bayreuth.

* If the following story is correct (and I have no reason to doubt my informant), the action of chloroform may, under certain circumstances, be considered analogous to hypnotism. At one of the large Metropolitan hospitals there existed, about forty years ago, a club of medical students, called the ' Chloroform Club,' the chief object of which was to test the action of narcotics, and especially of chloroform. The members met in each other's rooms, and consumed physiolog doses of various drugs. On this remembered occasion chloroform was the narcotic chosen, and one of the members was, as usual, told off to keep sober and watch his companions. But the temptation proved too great for him, and he also inhaled a considerable dose of the poison. Into this room full of drug-excited young men came a late member who was extremely unpopular with the others, and one of them shouted, ' Here's ------! Let us kill him !' The horrible suggestion at once took possession of the whole party. They flung themselves on the new-comer, and a tragedy would certainly have followed had not some students in another room heard the victim's cries of terror. They, of course, rushed in, and made a forcible rescue.

The affair was hushed up, and the club dissolved; but some of those who took part in the episode, which in its weird horror reminds one of the situations of Theophile Gautier, are now respected members of the profession, and will remember the occurrence.

The word 'assassin ' is said to be a corruption of ' hashish,' and to have originated from the use made of the drug by a sect of religious fanatics in Persia to remove their enemies. They induced heavenly visions, which they assured their followers were real and the reward of assassination.

Dr. Barwise writes (op. cit., p. 10) that, when experimenting with the drug on himself, he imagined the slight noise made by some one in turning over the pages of a book to be a thunderstorm. Dr. Von Schrenk-Notzing has written an exhaustive treatise on hashish, and he finds that some persons while under its influence are as susceptible to verbal suggestion as if they were hypnotized. One of the men experimented on was a medical student, who not only obeyed all the suggestions made to him while under the influence of the drug, but also carried out suggestions made the next day (post-narcotic suggestions), and that without having any recollection of the order. For example, he was told to return to Von Schrenk-Notzing's house the following day, and to ask him for three cigarettes. This he did, and in the same awkward and shamefaced manner as often characterizes compliance with post-hypnotic suggestions ('Die Bedeutung narco-tischer Mittel fur den Hypnotismus,' p. 67).

In alcoholic and other forms of intoxication there is commonly an exaggerated automatic action, as seen in gesture, speech, and general demeanour, with corresponding inhibition of the higher and controlling centres, and increased readiness to act upon suggestion, whether it be self-supplied by the senses, or from without, by the bystanders. It is known that epileptics are extremely susceptible to suggestion, and any action suggested to one immediately after an attack would probably be executed automatically, without volition, and without subsequent recollection of its performance. This point is noticed by Sir W. Gowers, and is interesting, as these subjects are peculiarly susceptible to hypnotism, perhaps because their cerebral centres are abnormally easy to dissociate and throw out of gear. * Increased suggestibility is the most prominent characteristic of the curious Malayan disease, latah.

With our present knowledge, it seems impossible to explain certain phenomena connected with advanced hypnotism. Some of these, which have often been attributed to clairvoyance, are undoubtedly the result of exaggerated perception and sensory hyperesthesia. The subject will, under the stimulation of suggestion, read figures or letters at an amazing distance, will distinguish persons by a sense of touch too delicate to exist when the other faculties are at work, will feel the apparently imperceptible currents of air set in motion by 'magnetic' passes, and will comprehend and act upon hints and whispers which are inaudible to the ordinary listener. Why should the hypnotized subject be deaf to all sounds except the voice of the operator, and hear and obey that voice, though it be but the faintest whisper, and the surrounding sounds a perfect babel? The waking of a tired mother at the feeblest cry of her infant, though loud noises are unnoticed by her, and that of Nelson's signal-lieutenant at the word 'Signal,' though the roaring of the cannon had failed to arouse him, may afford an analogy, if not an explanation.