r is in some bodies powerfully increased by heat, and
in others diminished, yet without our perceiving any accompanying essential
electrical difference, either in the bodies or in the changes occasioned by
the electricity conducted.

446. A numerous class of bodies, insulating electricity of low intensity,
when solid, conduct it very freely when fluid, and are then decomposed by
it.

447. But there are many fluid bodies which do not sensibly conduct
electricity of this low intensity; there are some which conduct it and are
not decomposed; nor is fluidity essential to decomposition[A].

[A] See the next series of these Experimental Researches.

448. There is but one body yet discovered[A] which, insulating a voltaic
current when solid, and conducting it when fluid, is not decomposed in the
latter case (414.).

[A] It is just possible that this case may, by more delicate
experiment, hereafter disappear. (See now, 1340, 1341, in relation to
this note.--_Dec. 1838._)

449. There is no strict electrical distinction of conduction which can, as
yet, be drawn between bodies supposed to be elementary, and those known to
be compounds.

_Royal Institution,
April 15, 1833_.

FIFTH SERIES.

S 11. _On Electro-chemical Decomposition._ P i. _New conditions of
Electro-chemical Decomposition._ P ii. _Influence of Water in
Electro-chemical Decomposition._ P iii. _Theory of Electro-chemical
Decomposition._

Received June 18,--Read June 20, 1833.

S 11. _On Electro-chemical Decomposition._[A]

[A] Refer to the note after 1047, Series viii.--_Dec. 1838._

450. I have in a recent series of these Researches (265.) proved (to my own
satisfaction, at least,) the identity of electricities derived from
different sources, and have especially dwelt upon the proofs of the
sameness of those obtained by the use of the common electrical machine and
the voltaic battery.

451. The great distinction of the electricities obtained from these two
sources is the very high tension to which the small quantity obtained by
aid of the machine may be raised, and the enormous quantity (371. 376.) in
which that of comparatively low tension, supplied by the voltaic battery,
may be procured; but as their actions, whether magnetical, chemical, or of
any other nature, are essentially the same (360.), it appeared evident that
we might reason from the former as to the manner of action of the latter;
and it was, to me, a probable cons