THE ANIMAL A MACHINE 



197 



charged. In the torpedo the positive pole is above, the 

 negative pole below; in the electrical eel the positive pole 

 is in front and the negative pole behind. (Fig. 78.) 



The arrangement of the batteries in the eel is obviously 

 very effective as a weapon. Under the action of nerve im- 

 pulses passing from the brain of the fish, its whole body 



Fir;. 77. The Electric Eel 



This fish has the most powerful electrical organs known; it can dispense 

 shocks approximating a voltage of 100 volts. 



•> . > i ' ' , 



^ * ' * ~* * • . 



- \ ' ' ' » \ ' • 



*•. v V ' .' .' ,' —- -^ ~v \ I / ' ,-- 



' ' \ V. ,-' ' f \ \ 



I ' / 1 \ \ 



\ 



Fig. 78. Lines of Electric Discharge in the Electric Eel 



becomes a powerful electric battery. The lines of current 

 radiate around the positive pole in front to join the negative 

 pole behind. (Fig. 78.) This body, producing electricity 

 of high voltage, is surrounded by water, which is a good con- 

 ductor. Smaller fish that come within the sphere of these 

 currents are electrocuted even if they do not touch the eel, 

 particularly since the movements of the pursuing eel adds 



