The following passage from that learned author seems to have been overlooked by those of his commentators who seek for evidence in his experiments to prove that suggestion is a necessary factor in the induction of the hypnotic condition:-- "In order to prove my position still more clearly, I called up one of my men-servants, who knew nothing of mesmerism, and gave him such directions as were calculated to impress his mind with the idea that his fixed attention was merely for the purpose of watching a chemical experiment in the preparation of some medicine, and being familiar with such, he could feel no alarm. In two minutes and a half his eyelids closed slowly with a vibrating motion, his chin fell on his breast, he gave a deep sigh, and instantly was in a profound sleep, breathing loudly.... In about one minute after his profound sleep I aroused him and pretended to chide him for being so careless, said he ought to be ashamed of himself for not being able to attend to my instructions for three minutes without falling asleep, and ordered him downstairs. In a short time I recalled this young man, and desired him to sit down once more, but to be careful not to go to sleep again, as on the former occasion. He sat down with this intention; but at the expiration of two minutes and a half his eyelids closed, and exactly the same phenomena as in the former experiment ensued."[15] Now, whilst it is true that Braid did not realize the supreme potency of suggestion as it is now understood by the Nancy school, he did intelligently eliminate it in the experiment above related. It was his purpose to demonstrate his theory that "the phenomena of mesmerism were to be accounted for on the principle of a derangement of the state of the cerebro-spinal centres, and of the circulatory and respiratory and muscular systems."[16] In other words, he was seeking to demonstrate his theory that the phenomena of mesmerism are attributable to a physical rather than a mental cause. Hence his care to select a subject who knew nothing of what was expected of him. Braid relates another circumstance equally demonstrative of the proposition that suggestion is not a necessary factor in the induction of the hypnotic state. He says:--