S46 Humboldt on Electrical Eels, and the method 
one of us received shocks, which the other did not feel. It de- 
pends upon the gymnotus to act toward the point where it finds 
itself the most strongly irritated. The discharge is then made 
at one point only, and not at the neighbouring points. If two 
persons touch the belly of the fish with their fingers, at an inch 
distance, and press it simultaneously, sometimes one, sometimes 
the other, will receive the shock. In the same manner, when 
one insulated person holds the tail, and another pinches the 
gills, or pectoral fin, it is often the first only by whom the shock 
is received. It did not appear to us, that these differences 
could be attributed to the dryness or dampness of our hands, 
or to their unequal conducting power. The gymnotus seemed 
to direct its strokes sometimes from the whole surface of its 
body, sometimes from one point only. 
Nothing proves more strongly the faculty which the gymno- 
tus possesses, of darting and directing its stroke according to 
its will, than the observations made at Philadelphia, and re- 
cently at Stockholm, on gymnoti rendered extremely tame. 
When they had been made to fast a long time, they killed from 
afar small fishes put into the tub. They acted at a distance ; 
that is to say, their electrical stroke passed through a very thick 
stratum of water. We need not be surprised, that what was ob- 
served in Sweden, on a single gymnotus only, we could not see 
on a great number of individuals in their native country. The 
electric action of animals being a vital action, and subject to 
their will, it does not depend solely on their state of health and 
vigour. A gymnotus, that has made the voyage from Surinatn 
to Philadelphia and Stockholm, accustoms itself to the impri- 
sonment to which it is reduced ; it resumes by degrees the same 
habits in the tub which it had in the rivers and pools. An elec- 
trical eel was brought to me at Calabozo, taken in a net, and 
consequently having no wound. It ate meat, and terribly 
frightened the little tortoises and frogs, which, not knowing the 
danger, placed themselves with confidence on its back. The 
frogs did not receive the stroke till the moment when they 
touched the body of the gymnotus. When they recovered, 
they leaped out of the tub ; and when replaced near the fish, 
they were frightened at its sight only. We then observed no- 
thing that indicated an action at a distance ; but our gymno- 
