128 ACTION OF TUB BE AIN AND NERVES. 
bringing it near tlie organs or insulating the fish, covering 
it with a metallic plate, and causing the plate to communi- 
cate by a conducting wire with the condenser of Volta, 
\\ e were at great pains to vary the experiments by which 
we sought to render the electrical tension oi the torpedo 
sensible ; but they were constantly without effect, and per- 
fectly confirmed what M. Bonplaud and myself had observed 
respecting the gymnoti, during our abode in South America. 
Electrical fishes, when very vigorous, act with equal 
energy under water and in the air. This observation led us 
to examine the conducting property of water; and we found 
that, when several persons form the chain between the 
superior and inferior surface oi the organs of the torpedo, 
the shock is felt only when these persons join hands. Th6 
action is not intercepted if two persons, who support the 
torpedo with their right hands, instead of taking one 
another by the left hand, plunge each a metallic point into 
a drop of water placed on an insulating substance. On 
substituting flame for the drop of water, the communication 
is interrupted, and is only re-established, as in the gym- 
notus, when the two points immediately touch each other in 
the interior of the flame. 
We are, doubtless, very far from having discovered all 
the secrets of the electrical action of fishes which is modified 
by the influence of the brain and the nerves; but the 
experiments we have just described are sufficient to prove 
that these fishes act by a concealed electricity, and by elec- 
tromotive organs of a peculiar construction, which are 
recharged with extreme rapidity. Volta admits that the 
discharges of the opposite electricities in the torpedos and 
the gymnoti are made by their own skin, and that when we 
touch them with one hand only, or by means of a metallic 
point, we feel the effect of a lateral shock, the electrical 
current not being directed solely the shortest way. When 
a Leyden jar is placed on a wet woollen cloth (which is a 
bad conductor), and the jar is discharged in such a manner 
that the cloth makes part of the chain, prepared frogs, 
placed at different distances, indicate by their contractions 
that the current spreads itself over the whole cloth in a 
thousand different ways. According to this analogy, the 
most violent shock given by the gynmotui at a distance 
