in this country by the publication of the account of a severe operation performed in 1829 by M. Cloquet, one of the most eminent surgeons of Paris, on a female patient who had been thrown by mesmerism into a state of somnambulism; in which, though able to converse with those around her, she showed herself entirely insensible to pain, whilst of all that took place in it she had subsequently no recollection whatever. About twelve years afterwards, two amputations were performed in our country, one in Nottinghamshire, and the other in Leicestershire, upon mesmerised patients, who showed no other sign of consciousness than an almost inaudible moaning; both of them exhibiting an uninterrupted placidity of countenance, and declaring, when brought back to their ordinary state, that they were utterly unaware of what had been done to them during their sleep. And not long afterwards, Dr. Esdaile, a surgeon in Calcutta, gave details of numerous most severe and tedious operations performed by him, without the infliction of pain, upon natives in whom he had induced the mesmeric sleep; the rank of Presidency Surgeon being conferred upon him by Lord Dalhousie (then Governor-General of India), 'in acknowledgment of the services he had "rendered to humanity." The results of minor experiments performed by various persons desirous of testing the reality of this state, were quite in harmony with these. Writing in 1845, Dr. Noble, of Manchester with whom I was early brought into association by Sir John Forbes in the pursuit of this enquiry,) said:

"We have seen a needle thrust deeply under the

nail of a woman sleeping mesmerically, without its exciting a quiver; we have seen pungent snuff in large quantities passed up the nostrils under the same circumstances, without any sneezing being produced until the patient was roused, many minutes afterwards: we have noticed an immunity from all shock when percussion caps have been discharged suddenly and loudly close to the ear; and we have observed a patient's little finger in the flame of a candle, and yet no indication of pain. In this latter case all idea of there having been courageous dissimulation was removed from our mind, in seeing the same patient evince both surprise and indignation at the treatment received; as, from particular circumstances, a substantial inconvenience was to result from the injury to the finger, which was by no means slight."1

This 'mesmeric sleep' corresponds precisely in character with what is known in medicine as 'hysteric coma;' the insensibility being as profound, while it lasts, as in the coma of narcotic poisoning or pressure on the brain; but coming on and passing off with such suddenness as to show that it is dependent upon some transient condition of the sensorium, which, with our present knowledge, we can pretty certainly assign to a reduction in the supply of blood caused by a sort of spasmodic contraction of the blood-vessels. That there is no adequate ground for regarding it as otherwise than real, appears further from the discovery made not long afterwards by Mr. Braid, a surgeon practising at Manchester, that he could induce it by a

1 British and Foreign Medical Review, April 1845.

very simple method, which is not only even more effective than the 'passes' of the mesmeriser, but is moreover quite independent of any other will than that of the person who subjects himself to it. He found that this state (which he designated as Hypnotism) could be induced in a large proportion of individuals of either sex, and of all ranks, ages, and temperaments, who determinately fix their gaze for several minutes consecutively on an object brought so near to their eyes, as to require a degree of convergence of their axes that is maintainable only by a strong effort.1

The first state thus induced is usually one of profound comatose sleep; the 'subject' not being capable of being roused by sensory impressions of any ordinary kind, and bearing without the least indication of consciousness what would ordinarily produce intolerable uneasiness or even severe pain. But after some little time, this state very commonly passes into one of somnambulism, which again corresponds

1 Mr. Braid's peculiar success in inducing this state seemed to depend partly upon his mode of working his method, and partly upon the 'expectancy' of his subjects. Finding a bright object preferable, he usually employed his silver lancet-case, which he held in the first place at ordinary reading distance, rather above the plane of the eyes; he then slowly approximated it towards the middle point, a little above the bridge of the nose, keeping his own eyes steadily fixed upon those of his 'subject,' and watching carefully the direction of their axes. If he perceived their convergence to be at all relaxed, he withdrew the object until the axes were both again directed to it; and then again approximated it as closely as was compatible with their continued convergence. When this could be maintained for a sufficient length of time upon an object at no more than about three inches distance, the comatose state generally supervened.

closely on the one hand with natural, and on the other with mesmeric somnambulism. In fact, it has been by the study of the Somnambulism artificially induced by Mr. Braid's process, that the essential nature of this condition has been elucidated, and that a scientific rationale can now be given of a large proportion of the phenomena reported by Mesmerisers as having been presented by their somnambules.

It has been claimed for certain Mesmeric somnambules, however, that they occasionally possess an intelligence altogether superhuman as to things present, past, and future, which has received the designation 'lucidity;' and it is contended that the testimony on which we accept the reality of phenomena which are conformable to our scientific experience, ought to satisfy us equally as to the genuineness of those designated as 'the higher,' which not only transcend, but absolutely contradict, what the mass of enlightened men would regard as universal experience. This contention, however, seems to me to rest upon an entirely incorrect appreciation of the probative force of evidence; for, as I shall endeavour to prove to you in my succeeding lecture, the only secure basis for our belief on any subject, is the confirmation afforded to external testimony by our sense of the inherent probability of the fact testified to; so that, as has been well remarked, "evidence tendered in support of what "is new must correspond in strength with the degree "of its incompatibility with doctrines generally admitted as true; and, where statements obviously contravene "all past experience and the universal consent of man

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"kind, any evidence is inadequate to the proof, which "is not complete, beyond suspicion, and absolutely in"capable of being explained away."

Putting aside for the present the discussion of these asserted marvels, I shall try to set before you briefly the essential characters which distinguish the state of Somnambulism (whether natural or induced), on the one hand from dreaming, and on the other from the ordinary waking condition. As in both these, the mind is in a state of activity; but, as in dreaming, its activity is free from that controlling power of the will, by which it is directed in the waking state; and is also removed from this last by the complete ignorance of all that has passed in it, which is manifested by the 'subject' when called back to his waking sclf, although the events of one access of this 'second consciousness' may vividly present themselves in the next, as if they had happened only just before. Again, instead of all the senses being shut up, as in ordinary dreaming sleep, some of them are not only awake, but preternaturally impressible; so that the course of the somnambulist's thought may be completely directed by suggestions of any kind that can be conveyed from without through the sensechannels which still remain open. But further, while the mind of the ordinary dreamer can no more produce movements in his body than impressions on his sense-organs can affect his mind, that of the Somnambulist retains full direction of his body (in so far, at least, as his senses serve to guide its movements); so that he acts his dreams as if they were his waking