OF HEALTH AND HUMAN NATURE. 41 



see that the actions of the heart, lungs, &c. have daily intervals 

 of remission. 



The animal functions are much influenced by habit - } the vital 

 or organic are considered by Bichat as removed from its influence. 

 The power of habit over our sensations and voluntary motions 

 is manifest : yet I think it equally great over the organic func- 

 tions. The operation of food and of all descriptions of ingesta 

 is most remarkably modified by habit ; through it poisons be- 

 come comparatively innoxious, and divers bear a long suspension 

 of respiration. 



Bichat regards the passions as directly influencing the organic 

 functions only, and springing from the state of the organs of 

 that class. Here he is to me perfectly unintelligible. Vexation 

 indeed disturbs the stomach, and fear augments the quantity of 

 urine ; but does not vexation equally and as directly disturb the 

 mind confuse the understanding, and occasion heat and pain 

 of the forehead ? Are not, in fact, the passions a part of the 

 mind : a part of the animal functions ? They powerfully affect, 

 it is true, the organic or vital functions, but this shows the close 

 connection merely between the two classes of functions. 



This connection is conspicuous in respiration, the mechanical 

 part of which belongs to the animal functions, the other to the 

 organic ; and in the alimentary actions, in which the food is 

 swaUowed and the faeces rejected by volition, and digestion, 

 &c. performed, independently of our influence, by the powers of 

 simple life. So close indeed is this connection, that every organ 

 of the animal class is the seat of organic functions ; in the vo- 

 luntary muscles, the organs of sense, and even in the brain, cir- 

 culation, secretion, and absorption are constantly carried on. 

 This connection is likewise apparent in the property of sensibility. 

 In the language of Bichat there are animal sensibility and contrac- 

 tility, and organic sensibility and contractility, besides the common 

 extensibility of matter, which he terms extensibilite de tissu, and 

 common contractility upon the removal of distention, Con- 

 tractilite par defaut d'extension, confounded by Blumenbach 



