Dumont-Pallier and Magnin accede to the theory of intermediate stages, and have tried to lay down rules for them with as great exactness as Charcot's school. They also are very decided about the three periods, whose succession does not appear to them as fixed; but they discovered a new fundamental law which regulates the production as well as the cessation of the condition--_La cause qui fait, defait_; that is, the stimulus which produces one of the three periods needs only to be repeated in order to do away with that condition. From this the following diagram of hypnotic conditions is evolved: [Illustration] And, furthermore, Dumont-Pallier should be considered as the founder of a series of experiments, for he was the first one to show in a decisive manner that the duality of the cerebral system was proved by these hypnotic phenomena; and his works, as well as those of Messrs. Berillon and Descourtis, have brought to light the following facts: Under hypnotic conditions, the psychical activity of a brain hemisphere may be suppressed without nullifying the intellectual activity or consciousness. Both hemispheres may be started at the same time in different degrees of activity; and also, when the grade is the same, they may be independently the seat of psychical manifestations which are in their natures entirely different. In close connection with this and with the whole doctrine of hemi-hypnotism, which is founded upon these facts, stand the phenomena of thought transference, which we must consider later. As an addition to the investigations of Charcot and Dumont-Pallier, Bremaud, in 1884, made the discovery that there was a fourth hypnotic state, "fascination," which preceded the three others, and manifested itself by a tendency to muscular contractions, as well as through sensitiveness to hallucination and suggestion, but at the same time left to the subject a full consciousness of his surroundings and remembrance of what had taken place. Descourtis, in addition, perceived a similar condition in the transition from hypnotic sleep to waking, which he called _delire posthypnotique_, and, instead of using the word "fascination" to express the opening stage, he substituted "captation." According to him, the diagram would be the following: [Illustration] This whole movement, which I have tried to sketch, and whose chief peculiarity is that it considers hypnotism a nervous malady, and one that must be treated clinically and nosographically, was opposed in 1880 in two directions--one source of opposition producing great results, while the other fell to the ground. The latter joined itself to the theory of the mesmerists, and tried, by means of exact experiments, to measure the fluid emanating from the human body--an undertaking which gave slight promise of any satisfactory result.