CHAP. XI.] MESMEEISM. 371 



reply when addressed, and resume the waking state, the power 

 which many unquestionably have of limiting the duration of sleep 

 to a predetermined period, as contrasted with the deep uncon- 

 sciousness and slowness to awake of others, strongly favour this 

 idea. 



This state, with which the revolution of each diurnal period 

 makes us familiar, as one of repose to the great centres of mental 

 nervous actions "tired Nature's sweet restorer" occurs, with 

 modifications, as the result of certain morbid processes, as the effect 

 of certain physical agents, or even as the consequence of pecu- 

 liar states of mind. Thus, under the influence of pressure, from 

 a clot of blood compressing the brain, or from lymph or fluid at its 

 base, a state varying from that of drowsiness up to the profound- 

 est sleep, or coma, may be induced. Whatever be the nature of 

 the compressing substance, or wherever situate, if the hemispheres 

 experience general pressure, this~result will ensue. Again, a class 

 of drugs, of the sedative or narcotic kind, exerts a similar influence ; 

 and, if given in too large a dose, will paralyse the brain. We 

 have daily evidence of this in the effects of opium, which para- 

 lyses at first the centres of mental actions, and ultimately those 

 of physical actions. Lastly, particular states of the system, in- 

 duced, perhaps, by deranged assimilation, or by great previous dis- 

 turbance of mind, dispose persons to fall into that state which is 

 called somnambulism. The somnambulist is one who dreams, and 

 acts in his dream as if he were awake, and as if all the phenomena 

 presented to him were real. He appears to the bystanders in a 

 deep sleep, but acts with wonderful precision, walks with steady 

 gait, and avoids obstacles. Yet frequently accidents, injurious or 

 even fatal, occur ; which shew that on such occasions he is asleep, 

 and has not the full command of his senses. Persons in this state 

 will answer questions rationally and with readiness, and do not 

 appear to be at all disturbed by being questioned. The hypochon- 

 driacal or hysterical diathesis disposes greatly to the development 

 of somnambulism both in male and female. 



A state remarkably analogous to this of somnambulism may be 

 induced in persons of nervous temperament, which has been called 

 the Mesmeric sleep, or trance. It requires for its production the 

 apparent influence of another individual, who watches the person 

 experimented on with an intent look, and makes certain movements 

 before him, which are called passes. All persons are not susceptible 

 of passing into this state, any more than they are of exhibiting the 

 phenomena of somnambulism. The same state of constitution which 



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