omposition already put forth, that their present contradictory and
unsatisfactory state may be seen before I give that which seems to me more
accurately to agree with facts; and I have ventured to discuss them freely,
trusting that I should give no offence to their high-minded authors; for I
felt convinced that if I were right, they would be pleased that their views
should serve as stepping-stones for the advance of science; and that if I
were wrong, they would excuse the zeal which misled me, since it was
exerted for the service of that great cause whose prosperity and progress
they have desired.
481. Grotthuss, in the year 1805, wrote expressly on the decomposition of
liquids by voltaic electricity[A]. He considers the pile as an electric
magnet, i.e. as an attractive and repulsive agent; the poles having
_attractive_ and _repelling_ powers. The pole from whence resinous
electricity issues attracts hydrogen and repels oxygen, whilst that from
which vitreous electricity proceeds attracts oxygen and repels hydrogen; so
that each of the elements of a particle of water, for instance, is subject
to an attractive and a repulsive force, acting in contrary directions, the
centres of action of which are reciprocally opposed. The action of each
force in relation to a molecule of water situated in the course of the
electric current is in the inverse ratio of the square of the distance at
which it is exerted, thus giving (it is stated) for such a molecule a
_constant force_[B]. He explains the appearance of the elements at a
distance from each other by referring to a succession of decompositions and
recompositions occurring amongst the intervening particles[C], and he
thinks it probable that those which are about to separate at the poles
unite to the two electricities there, and in consequence become gases[D].
[A] Annales de Chimie, 1806, tom, lviii. p. 64.
[B] Ibid. pp. 66, 67, also tom. lxiii. p. 20.
[C] Ibid. tom. lviii. p. 68, tom, lxiii. p. 20.
[D] Ibid. tom. lxiii. p. 34.
482. Sir Humphry Davy's celebrated Bakerian Lecture on some chemical
agencies of electricity was read in November 1806, and is almost entirely
occupied in the consideration of _electro-chemical decompositions_. The
facts are of the utmost value, and, with the general points established,
are universally known. The _mode of action_ by which the effects take place
is stated very generally, so generally, indeed, that probably a dozen
precise
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