340 ELECTRICAL FISH. [SECT. xxix. 



and an acid taste is perceived when the positive wire is 

 applied to the tip of the tongue, and the negative wire 

 touches some other part of it. By reversing the poles the 

 taste becomes alkaline. It renders the pale light of the 

 glow-worm more intense. Dead animals are roused by it, 

 as if they started again into life, and it may ultimately 

 prove to be the cause of muscular action in the living. 



Several fish possess the faculty of producing electrical 

 effects. The most remarkable are the gymnotus electricus, 

 found in South America ; and the torpedo, a species of ray, 

 frequent in the Mediterranean. The electrical action of the 

 torpedo depends upon an apparatus apparently analogous 

 to the Voltaic pile, which the animal has the power of 

 charging at will, consisting of membranous columns filled 

 throughout with laminae, separated from one another by a 

 fluid. The absolute quantity of electricity brought into 

 circulation by the torpedo is so great, that it affects the 

 decomposition of water, has power sufficient to make 

 magnets, gives very severe shocks and the electric spark. 

 It is identical in kind with that of the galvanic battery, 

 the electricity of the under surface of the fish being the 

 same with the negative pole, and that in the upper surface 

 the same with the positive pole. Its manner of action is, 

 however, somewhat different ; for, although the evolution of 

 the electricity is continued for a sensible time, it is inter- 

 rupted, being communicated by a succession of discharges. 



