36 OF VITAL MOTION. 



(a.) Of the nervous influence as an agent in the 

 capillary movements. 



It is not our purpose to consider the abstract pro- 

 perties of the nervous system, and the high and 

 mystical communion between it and the intelligence 

 of man, but simply to examine the physical relation 

 which exists between this system as matter and the 

 rest of the organism. 



The physical mode in which the nervous influence 

 affects the capillary vessels for there is such a tan- 

 gible mode of action may be ascertained without any 

 diflficulty. When, for instance, the mind is paralysed 

 by fear, the skin becomes pale and blanched, in con- 

 sequence of the shrinking of its vessels; and not only 

 so, but if the bodily frame be fragile and delicate, the 

 deadening influence extends to the heart, and a state 

 of syncope or entire suspension of circulation is the 

 result: when, on the other hand, the frame thrills 

 under the excitement of joy, and the nervous power 

 is exuberant, the countenance becomes radiant, the 

 skin is suffused with blood, and the heart beats with 

 increased vigour. These phenomena afford a twofold 

 illustration of the importance of the nervous principle 

 as an " agent of life," and of the nature of the agency 

 physically considered. 



As evidenced in the capillary vessels, therefore, the 

 effects of an exuberant or deficient supply of nervous 



