an take place with good conductors,
proves that with soap, &c. many of the effects are the mere consequences of
the bodies evolved by electrolytic action.

[A] Erman, Annales de Chimie, 1807. lxi. p. 115. Davy's Elements, p.
168. Biot, Ency. Brit. Supp, iv. p. 444. Becquerel, Traite, i. p. 167.
De la Rive, Bib. Univ. 1837. vii. 392.

[B] Erman, Annales de Chimie, 1824. xxv. 278. Becquerel, Ibid. xxxvi.
p. 329

[C] Becquerel, Annales de Chimie, 1831. xlvi. p. 283.

[D] Andrews, Philosophical Magazine, 1836. ix. 182.

[E] Schweigger's Jahrbuch de Chimie, &c. 1830. Heft 8. Not
understanding German, it is with extreme regret I confess I have not
access, and cannot do justice, to the many most valuable papers in
experimental electricity published in that language. I take this
opportunity also of stating another circumstance which occasions me
great trouble, and, as I find by experience, may make, me seemingly
regardless of the labours of others:--it is a gradual loss of memory
for some years past; and now, often when I read a memoir, I remember
that I have seen it before, and would have rejoiced if at the right
time I could have recollected and referred to it in the progress of my
own papers.--M.F.

1636. I conclude, therefore, that the _facts_ upon which the doctrine of
unipolarity was founded are not adverse to that unity and indivisibility of
character which I have stated the current to possess, any more than the
phenomena of the pile itself (which might well bear comparison with those
of unipolar bodies,) are opposed to it. Probably the effects which have
been called effects of unipolarity, and the peculiar differences of the
positive and negative surface when discharging into air, gases, or other
dielectrics (1480. 1525.) which have been already referred to, may have
considerable relation to each other[A].

[A] See also Hare in Silliman's Journal, 1833. xxiv. 246.

* * * * *

1637. M. de la Rive has recently described a peculiar and remarkable effect
of heat on a current when passing between electrodes and a fluid[A]. It is,
that if platina electrodes dip into acidulated water, no change is produced
in the passing current by making the positive electrode hotter or colder;
whereas making the negative electrode hotter increased the deflexion of a
galvanometer affected by the current, from 12 deg. to 30 deg. and even 45 deg., whilst
making it co