The Voltaic Pile 165

and almost a natural consequence, that the quantity which
passes is the equivalent of, and therefore equal to, that of the
particles separated; i.e. that if the electrical power which holds
the elements of a grain of water in combination, or which makes
a grain of oxygen-and hydrogen in the'right proportions unite
into water when they are made to combine, could be thrown
into the condition of a current, it would exactly equal the current
required for the separation of that grain of water into its ele-
ments again.

591. This view of the subject gives an almost overwhelming
idea of the extraordinary quantity or degree of electric power
which naturally belongs to the particles of matter; but it is not
inconsistent in the slightest degree with the facts which can be
brought to bear on this point. To illustrate this I must say a
few words on the voltaic pile.1

592. Intending hereafter to apply the results given in this
and the preceding series of Researches to a close investigation
of the source of electricity in the voltaic instrument, I have
refrained from forming any decided opinion on the subject;
and without at all meaning to dismiss metallic contact, or the
contact of dissimilar substances, being conductors, but not
metallic, as if they had nothing to do with the origin of the
current, I still am fully of opinion with Davy, that it is at least
continued by chemical action, and that the supply constituting
the current is almost entirely from that source.

593. Those bodies which, being interposed between the
metals of the voltaic pile, render it active, are all of them elec-
trolytes (212); and it cannot but press upon the attention of
every one engaged in considering this subject, that in those
bodies (so essential to the pile) decomposition and the trans-
mission of a current are so intimately connected, that one can-
not happen without the other. This I have shown abundantly
in water, and numerous other cases (138, 212). If, then, a
voltaic trough have its extremities connected by a body capalole
of being decomposed, as water, we shall have a continuous
current through the apparatus; and whilst it remains in this
state we may look at the part where the acid is acting upon the
plates, and that where the current is acting upon the water, as

1 By the term voltaic pile, I mean such apparatus or arrangement of
metals as up to this time have been called so, and which contain water,
brine, acids, or other aqueous solutions or decomposable substances (212),.
between their plates. Other kinds of electric apparatus may be hereafter
invented, and I hope to construct some not belonging to the class of
instruments discovered by Volta.and the larger wires communicating with it be