[A] Precis Elementaire de Physique, 3me edition, 1824, tom. i. p. 636.

  [B] Ibid. p, 642.

488.  This theory implies that decomposition takes place at both poles upon distinct portions of fluid, and not at all in the intervening parts.  The latter serve merely as imperfect conductors, which, assuming an electric state, urge particles electrified more highly at the poles through them in opposite directions, by virtue of a series of ordinary electrical attractions and repulsions[A].

  [A] Precis Elementaire de Physique, 3me edition, 1824, tom. i. pp.
  638, 642.

489.  M.A. de la Rive investigated this subject particularly, and published a paper on it in 1825[A].  He thinks those who have referred the phenomena to the attractive powers of the poles, rather express the general fact than give any explication of it.  He considers the results as due to an actual combination of the elements, or rather of half of them, with the electricities passing from the poles in consequence of a kind of play of affinities between the matter and electricity[B].  The current from the positive pole combining with the hydrogen, or the bases it finds there, leaves the oxygen and acids at liberty, but carries the substances it is united with across to the negative pole, where, because of the peculiar character of the metal as a conductor[C], it is separated from them, entering the metal and leaving the hydrogen or bases upon its surface.  In the same manner the electricity from the negative pole sets the hydrogen and bases which it finds there, free, but combines with the oxygen and acids, carries them across to the positive pole, and there deposits them[D].  In this respect M. de la Rive’s hypothesis accords in part with that of MM.  Riffault and Chompre (485.).

  [A] Annales de Chimie, tom, xxviii. p. 190.

  [B] Ibid. pp. 200, 202.

  [C] Ibid. p. 202.

  [D] Ibid. p. 201.

490.  M. de la Rive considers the portions of matter which are decomposed to be those contiguous to both poles[A].  He does not admit with others the successive decompositions and recompositions in the whole course of the electricity through the humid conductor[B], but thinks the middle parts are in themselves unaltered, or at least serve only to conduct the two contrary currents of electricity and matter which set off from the opposite poles[C].  The decomposition, therefore, of a particle of water, or a particle of salt, may take place at either pole, and when once effected, it is final for the time, no recombination taking place, except the momentary union of the transferred particle with the electricity be so considered.

  [A] Annales de Chimie, tom, xxviii. pp. 197, 198.

  [B] Ibid. pp. 192, 199.

  [C] Ibid. p. 200.

491.  The latest communication that I am aware of on the subject is by M. Hachette:  its date is October 1832[A].  It is incidental to the description of the decomposition of water by the magneto-electric currents (346.).  One of the results of the experiment is, that “it is not necessary, as has been supposed, that for the chemical decomposition of water, the action of the two electricities, positive and negative, should be simultaneous.”