288 Prof. Marianini on the Electric Shock, <^c. 



1 . The principles upon which the theory of Voltaic appara- 

 tuses hitherto rest, do not authorize us to admit in these appa- 

 ratuses a reflux of electricity at the instant when the circuit is 

 interrupted. 



2. When this reflux has taken place, the shock experienced 

 by the animal at the instant when it ceases to form part of the 

 circuit, cannot be attributed to it. 



3. The two kinds of contractions produced in the muscles 

 by electricity, viz. the Idiopathic contractions and the Sympa- 

 thetic contractions, deserve to be distinguished from one ano- 

 ther, in so far as the Jlrst take place whatever be the direction 

 according to which the current penetrates the muscles, and the 

 second only when the current runs along the nerves in the di- 

 rection of their ramification, that is, when the part where the 

 current enters the nerve is nearer the origin of the nerve than 

 the part at which the current comes out from it. 



4. The agitation which the animals experience when they 

 come suddenly to form part of an electric circuit, arises from 

 this, that the electricity, when it moves in the nerves in a di- 

 rection contrary to that of their ramification, produces a shock 

 at the instant when it ceases to penetrate it, and not when the 

 circulation is established. 



5. When the electric fluid penetrates the nerves in a direc- 

 tion contrary to that of their ramification, instead of occasioning 

 a contraction, it produces a sensation. 



6. The animal experiences a sensation at the instant when 

 we interrupt the electric current which runs along the nerve in 

 the direction of its ramification. 



