VITAL PHENOMENA. 



325 



muscles contract. The galvanic current or other artificial 

 irritant takes the place of the stimulus by which the nerve 

 fibres are thrown into action whenever the will of the animal 

 acts, or when a stimulus is transmitted from peripheral parts 

 by nerve fibres and their extensions which ramify centrally 

 in those particular spots of gray matter. The direct exci- 

 tation may be mechanical in all cases, but there is some- 

 thing behind the excitation, or which constitutes an 

 essential part of the changes which collectively make up 

 what is termed " excitation " that cannot be accounted 

 mechanical or chemical, but which is essential and absolute, 

 and without which excitation would be impossible and not 

 conceivable in thought. 



In the natural state, I believe, the little bioplasts which 

 I have described near the surface of the convolutions 

 initiate the changes which result in a mental act, and that 

 by the movements of these, the nerve mechanism is made 

 to act, just as in experiments it is excited to action by a 

 current of electricity. The change in the bioplasm is in all 

 cases a vital act, not to be accounted for by physics or 

 chemistry any more than the origin, formation, and struc- 

 ture of the nerve mechanism is to be so explained. Every 

 kind ^ of mental action, I venture to think, is initiated in 

 bioplasm, and is due to a purely vital change. So far, 

 therefore, from minute research tending to prove that con- 

 sciousness is in any way related to force, the tendency of 

 investigation is towards a very different inference. If I 

 were asked to name what, of or belonging to man, is furthest 

 removed from matter and its forces, I should answer, con- 

 sciousness, which belongs to the vital and not to the 

 material order. 



