232 MUSCULAR SYSTEM, 



to them. Cerebral influence and irritation are necessary 

 to animal contractility; now, as the will has no influence 

 over these muscles, animal contractility cannot be expect- 

 ed in them. Irritate the brain with the scalpel, with 

 opium, intoxication, wounds of the head, mania, and while 

 all these excite the animal contractility of the muscles of 

 animal life, there being no such property in the muscles 

 of organic life, they are unmoved. 



Q. But do you not find the brain affected by disorder 

 of the muscles of organic life? 



#. No in most vomitings, the irregular motions of the 

 intestines which take place in diarrhoeas, in affections of 

 the heart, &c. the brain is not diseased. 



Q. In syncope is the brain or heart first affected? 



.#. The heart is. 



Q. The brain does certainly influence the stomach 

 through the par vagum ? 



#. It does; but cutting the par vagum does not affect 

 the stomach as the section of a nerve going to a muscle 

 of animal life, does that muscle. While irritating the par 

 vagum induces the stomach to contract, yet if both nerves 

 of that pair be divided, violent vomiting is induced. Now 

 you never induce contraction in a muscle of animal life by 

 cutting off its supply of nervous influence. 



Q. Do you consider Bichat's arguments and facts with 

 regard to the independence of the organic muscles of ce- 

 rebral influence as conclusive? 



Jl. No. He is not convinced himself; for a mixed in- 

 fluence is admitted, with the nature of which he is unac- 

 quainted; but of one thing he is assured, that the cerebral 

 influence on the organic muscles is entirely different from 

 that on the animal muscles. 



