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other. No person, on the contrary, has ever 

 perceived a spark issue from the body of the fish 

 itself. We have irritated it for a long time dur^ 

 ing the night, at Calabozo, in perfect darkness, 

 without observing any luminous appearance. 

 Having placed four gymnoti of unequal strength 

 in such a manner as to receive the shocks of the 

 most vigorous fish by communication, that is to 

 say, by touching only one of the other fishes, I 

 did not observe, that these J as t were agitated at 

 the moment when the current passed by their 

 bodies. Perhaps the current established itself 

 only on the humid surface of the skin. We will 

 not however conclude from this, that the gym- 

 noti are insensible to electricity ; and that they 

 cannot fight with each other at the bottom of the 

 pools. Their nervous system must be subject 

 to the same agents as the nerves of other ani- 

 mals. I have indeed seen, that, on baring their 

 nerves, they undergo muscular contractions at 

 the simple contact of two heterogeneous metals ; 

 and Mr. Fahlberg, of Stockholm, found, that his 

 gymhotus was convulsively agitated, when placed 

 in a copper vessel, and feeble discharges from a 

 Leyden vial passed through it's skin. 



After the experiments I had made on gymnoti, 

 it became highly interesting to me, at my return 

 to Europe, to know with precision the various 

 circumstances, in which another electrical fish, 

 the torpedo of our seas, gives or does not give 



