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in the animal organs, and by their own proper force, by some particular action
of the vital powers. No, this is a mere artificial Electricity, induced by an
external cause, that is, excited originally in a manner hitherto unknown, by
the connexion of Metals with any kind of wet substance. And the animal or-
gans, the nerves and the muscles, are merely passive, though easily thrown
into action whenever, by being in the circuit of the Electric current, pro-
duced in the manner already mentioned, they are attacked and stimulated
by it, particularly the nerves.

I have said that this motion is given to the Electric fluid by the connexion
of Metals with any kind of wet substance. It should not therefore be necessary
(in order for the tongue to perceive the taste, or for the muscles of the Limbs
to be convulsed) that the two metals, Tin and Silver, or any other dissimilar
in themselves, should be applied to this or that part of the Animal. And this
is exactly the case; the same Phenomena take place, if one, or the other, or
both the metallic coatings are applied to a piece of wood, or pasteboard or
cloth well wetted, or to water itself. All that is required is, that the wet track,
that is to say, the series of wet substances rendered good conductors by the
water contained in them, or by that with which they are wetted, should not
be in the smallest degree interrupted. Then, if in this series, in this track,
through which the Electric stream will pass, as soon as the circuit is completed
from those metals which are connected with the wet substances, by making
them communicate with each other, either immediately, or by means of a
third metal; if, I say, in this continued series, or chain of wet substances
there should be placed, for instance, the crural nerves of a frog, or the
ischiatic nerve of a Lamb, etc. laid bare all around, in such a manner that
the whole of that current of electric fluid which is excited by the metallic
coatings, applied to the forementioned wet pasteboard, or cloth, must pass
through the narrow passage of those nerves only, or even through a small
portion of their length, the muscles governed by those nerves will contract
strongly, the leg, etc. will be violently agitated. If the tongue be so placed
that the current goes against the tip of it, and is obliged in like manner to enter
into it. by a narrow passage, the acid taste, etc. will be excited.

Hence, a thousand ways of making these Experiments may be thought of,
and indeed of all those I have tried, observing the conditions already pointed
out, in conformity to the principles I have established, and foretelling the
success with certainty, not one has failed me. By the way of example I will
here describe some of them. If a thin plate of Tin be applied to the tip of the
tongue (a strip of tinfoil is best of all) and a broad flat piece of Silver, for in-
stance, a Candlestick, or a large spoon be grasped either with the naked hand
wetted, or with the hand wrapped up in a wet napkin, and afterwards you
touch the tin with the silver, at the same moment the acid taste will be excited
upon the tongue, and it will continue as long as these contacts are kept up.