MUSCULAR SYSTEM. 225 



the nerves from the spine convey to the muscles of the 

 body and limbs, the principle of animal contractility. 

 This circumstance clearly shows the difference between 

 the voluntary and involuntary contractility. So that after 

 decapitation, and by the influence of galvanism, the prin- 

 ciple of animal contractility can be conveyed; that is, after 

 intellect and respiration, and the heart's action have irre- 

 coverably ceased. 



Q. Why is galvanism more powerful after death than 

 during life ? 



t/2. Because during life the will in a great measure 

 counteracts the irritation of the galvanic fluid. 



Q. What is the difference between animal contractility 

 and irritability? 



*ft. Animal contractility originates in the brain and 

 nerves, and its power is passively received by the mus- 

 cles. Irritability is an innate principle of motion in a 

 muscle; it exists before and after death. 



Q. In what part of the nervous system does animal 

 contractility cease first and last? 



#. It is first lost in the brain, next in the spinal mar- 

 row, last in the nerves; and it is excited by metallic irri- 

 tation when all other is inefficient. 



Q. By what means can you distinguish sensible organic 

 contractility from animal contractility? 



jl. Recollect that sensible organic contractility is or- 

 ganic action independent of the brain, the animal contrac- 

 tility is purely dependent on the brain. If you cut all the 

 nerves which convey influence to the muscle, still that 

 muscle on irritating it will contract; now this is the sen- 

 sible organic contractility, the irritability of physiologists. 



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