270 Prof. W. F. Barrett on the Alleged 



Two words more. 



In the state of somnambulism, of hysteric or hypnotic 

 neurosis, &c. the human subject may, in consequence of 

 certain practices, be plunged into a peculiar sleep most fre- 

 quently accompanied by catalepsy. Now during one phase 

 of this sleep (the so-called lethargic phase) the special 

 senses continue in part to act, and by speaking to them 

 the most various hallucinations may be set up in the 

 subjects. If we tell them that music is being played, 

 they hear it immediately; they see the various objects of 

 which we speak to them, they feel them and taste them. 

 These are well-known phenomena of suggestion which have 

 been much studied of late years. In certain invalids the field 

 of suggestion has, so to speak, no limits. It is interesting to 

 find that here the pathological state is only an exaggeration 

 of the normal state, since (as we have just seen) we may by 

 suitable discourses, by persuasion, &c. appeal to the attention 

 of the normal man, not put to sleep, in such a manner as to 

 make him have consciousness of sensations which do not cor- 

 respond to any objective reality. In both cases the repetition 

 of the hallucination leads to an augmentation of its intensity. 

 All neuropaths know that it is much easier to produce sug- 

 gestion in old subjects who have been long under the hands 

 of the mesmerists than in those who are put to sleep for the 

 first time. In our experiments we have always found that, 

 after two or three repetitions, the subjective sensation increased 

 in intensity, and that the persons whom one has sustained in 

 the belief in the " fluid" of the so-called magnetized card or 

 piece of money are much better fitted to serve for a demon- 

 stration than a person upon whom one has tried the experi- 

 ment for the first time, and who is not always very positive at 

 the commencement. 



To sum up, we demonstrate, under what may be termed an 

 embryonic form, in the healthy human subject, phenomena of 

 suggestion which may acquire great intensity in the diseased 

 subject. 



XL. Note on the Alleged Luminosity of the Magnetic Field. 

 By W. F. Barkett, Professor of Experimental Physics in 

 the Royal College of Science, Dublin*. 



IT is well known that the late Baron von Reichenbach 

 claimed to have discovered a peculiar luminous emana- 

 tion arising from the poles of a magnet, resembling a faint 



* Communicated by the Author. 



