PHYSIOLOGY. 149 



in which the stimulus being as usual, delirium occurs in con- 

 sequence of collapse taking place in a certain part. This is the 

 distinction between the delirium ferox and delirium mite, 

 which pathologists and practitioners have so constantly no- 

 ticed, and which, in the case of fever, will have a very con- 

 siderable influence upon our prognostic, as well as upon the con- 

 duct of our practice." 



CXLIII. With regard to the connexions established in the 

 system (CXX. CXXI.), it is to be observed, as of great conse- 

 quence in pathology, that certain parts of the body which have 

 a common function and constitution " I should rather say a 

 common function and peculiar constitution 1 ' have thereby a 

 peculiar relation to the brain, so as to be more liable to be af- 

 fected by the different states of it, and, in their turn, by the dif- 

 ference of their condition to affect the brain. Such are, espe- 

 cially, the organs of voluntary motion ; the alimentary canal, 

 and especially the stomach ; the circulatory system, and parti- 

 cularly the extremities of the vessels on the surface of the body ; 

 the uterine and genital system in females ; and some others to 

 be mentioned in the Pathology. " With regard to these, re- 

 member that the facts are certain, and therefore an object of 

 our attention and curiosity ; the reasons are doubtful : I do not 

 pretend to explain them either certainly or completely, but only 

 to make some approach. 



" The ' organs of voluntary motion" have this in common, 

 that their actions are in consequence of an action of the 

 brain, which occasions, increases, and excites them, while 

 the vital functions need only that general energy which is 

 constantly operating in the system. In consequence of this 

 exertion of the animal power, the organs of voluntary mo- 

 tion are subject to lassitude and debility, and require a state 

 of rest and of sleep. Hence also, various irritations of the 

 brain, exciting its action, are especially exerted in convulsive 

 motions of the organs of voluntary motion : hence palsy takes 

 place in the same organs, and many of their diseases are ex- 

 plained by this their peculiar connexion with the brain. 



" The ' alimentary canal, and especially the stomach.? are 

 commonly affected by the different states of the brain ; and the 

 stomach again has more effect upon the brain than any other 



