362 HYPNOTISM. 



the second, he moves the hand close to, but not touching, 

 the skin of the subject. The exact way in which sensory^ 

 stimulation is effected by these " passes " is disputed. Some 

 have thought that it is by the air currents excited : others, 

 that it is by the heat radiated from the hand, for this soon 

 gets hot, owing to the muscular exertion : others, again, 

 think that electrical currents are produced in the skin. 



It is pretty certain that the sole element common to all 

 these various methods is that they produce continuous slight 

 sensory stimulation. 



But hj^pnosis may be produced solely by the direct verbal 

 suggestion of sleep ; and this not only in persons who have 

 been previously hypnotised by physical means, but also in 

 persons who have never before been hypnotised. This is 

 the now celebrated method of the Nancy school of experi- 

 menters. This most important fact gives rise to the question 

 whether continuous sensory stimulation does not produce 

 hypnosis by indirectly suggesting it, and not as such, acting 

 physically only. And, except by the Salpetriere school, the 

 following opinion is now held : that monotonous sensory 

 stimulation of itself produces normal sleep ; but that in 

 hypnosis the essential thing is that the " subject " is sent 

 to sleep by the hypnotiser, who may do this by indirect 

 (monotonous sensory stimulation) or by direct (verbal) sug- 

 gestion. And this corresponds to the difference between 

 hypnosis and sleep ; i.e. in the former there is, in the latter 

 there is not, an increased suggestability to the h^-pnotiser. 



Practically, it is sometimes found that " passes " have 

 produced sleep, and not hypnosis. 



To dehypnotise a person, either verbal suggestion or a 

 stidden sensory stimulus ma}^ be employed. Thus one may 

 say, two or three times, " Wake up," or " Count up to ten : 

 when you say ' ten,' you will wake up " ; or one may blow 



