372 INNERVATION. [CHAP. XT. 



disposes to the latter is favourable to the former. Remarkable 

 statements have been made, and confirmed by the testimony of a 

 larger number of observers, tending to imply that in these cases the 

 faculties become exalted in an extraordinary manner; and that the 

 individual acquires powers of a novel description, and even of a 

 superhuman kind. It behoves all sober-minded persons to be slow 

 to accept such statements as true, and, without impugning the vera- 

 city of the reporters, to inquire whether they do not rest more upon 

 a misinterpretation than upon a misrepresentation of facts. The 

 polar force of the mental nervous centres may, in this peculiar state, 

 be so affected as to favour the development of subjective pheno- 

 mena, which it is evident may assume particular forms under the 

 influence of impressions made from time to time upon the senses. 

 The ravings of a delirious or of a lunatic patient often take a parti- 

 cular direction under the influence of a question or remark let fall 

 by some bystander ; it is not unlikely that persons, with a mental 

 bias for the marvellous, might discover in such patients quite as 

 much evidence of superhuman power, as has been adduced by the 

 Mesmerists. 



We cannot avoid remarking, how much it is to be lamented that 

 inquiries of so delicate a nature, affecting the very confines between 

 mind and matter, should have usually fallen into the hands of per- 

 sons ill qualified for such pursuits, either by mental constitution or 

 by previous experience in the study of subjects involving both phy- 

 sical and metaphysical knowledge. Little is to be expected in such 

 difficult researches from dilettanti of either sex; much less from 

 those whose excessive zeal for novelty and notoriety must necessarily 

 cast suspicion on their statements. Nor can we hope that truth can 

 oe elicited from experiments and observations which are made be- 

 fore the public gaze, with more of the characters of a theatrical 

 exhibition than of a sober philosophical investigation. 



Functions of the Commissures. The commissures of the brain 

 have long been regarded as provisions to ensure the harmonious 

 co-operation of certain parts of the nervous centres, whether on 

 the same or on opposite sides. This opinion rests mainly upon 

 their anatomical connexions ; for but little that is satisfactory can 

 be concluded from either the comparative anatomy or pathological 

 conditions of them. It is evident that the principal commissures 

 bear a direct ratio in point of development to that of certain 

 parts ; and that, when those parts are imperfect or absent, the 

 commissures are deficient or wholly wanting. Thus the corpus 

 callosum and the hemispheres are developed together; the fornix 





