924 OF MUSCULAR MOVEMENTS. 



Until, therefore, it shall have been proved by. an extended course of carefully 

 conducted experiments, that this mode of explanation is inadequate to account 

 for the phenomena in question, all that is genuine in what is at present known 

 may be set down to the category of Ideo-motor actions, or reflex actions of the 

 (Jerebrum ( 683). 



926. To this same category are doubtless to be referred a large number of 

 those actions of Mesmeric " subjects" which have been considered by some as 

 most unequivocal indications of the existence of an agency sui generis, whilst 

 by others they have been regarded as the results of intentional deception. Now 

 many of them are of a kind which the Will could not feign, being violent con- 

 vulsive movements, such as no voluntary effort could produce ; but the Mes- 

 meric " subject" being previously possessed with the expectation that certain 

 results will follow certain actions (as, for instance, that convulsive movements 

 will be brought on by touching a piece of mesmerized metal), and the whole 

 nervous power being concentrated, as it were, upon the performance, the move- 

 ments follow when the subject believes the conditions to have been fulfilled, 

 whether they have been, or not. These facts were most completely established 

 by the commission appointed to investigate the pretensions of Mesmer himself; 

 and whilst they demonstrate the unreality of the supposed mesmeric influence 

 (so far, at least, as this class of phenomena is concerned), they also prove the 

 position here contended for, namely, the sufficiency of the state of expectant 

 attention, in those whose minds can be completely possessed by it, to produce 

 effects of the same nature with those which are induced in Hysterical subjects 

 by emotional excitement. 1 



CHAPTER XVII. 



OF THE VOICE AND SPEECH. 



1. Of the Larynx, and its Actions. 



927. THE sounds produced by the organ of Voice constitute the most import- 

 ant means of communication between Man and his fellows; and the power of 

 Speech has, therefore, a primary influence, as well on his physical condition as 

 on the development of his mental faculties. In order to understand the nature 

 of this organ as a generator of Sound, it is requisite to inquire, in the first 

 instance, into the sources from which sounds at all corresponding to the Human 

 voice are elsewhere obtained. It is necessary to bear in mind that Vocal 

 sounds, and speech or articulate language, are two things entirely different; and 

 that the former may be produced in great perfection, where there is no capa- 

 bility for the latter. Hence we should at once infer that the instrument for the 

 production of vocal sounds was distinct from that by which these sounds are 

 modified into articulate speech; and this we easily discover to be the case, the 

 voice being unquestionably produced in the larynx, whilst the modifications of 

 it by which language is formed are effected for the most part in the oral cavity. 

 The structure and functions of the former, then, first claim our attention. 



1 On the whole of this subject, the Author has the satisfaction of referring to the essay 

 on "The Effects of Attention on Bodily Organs," in Dr. Holland's "Chapters on Mental 

 Physiology," as showing the essential coincidence between the opinions of this distin- 

 guished Physician, and those at which he had himself arrived by independent inquiry. 



