[A] Annales de Chimie, xxi. pp. 127, 178.

442.  I cannot but suppose at present that at that point where the liquid and the gaseous state coincide, the conducting properties are the same for both; but that they diminish as the expansion of the matter into a rarer form takes place by the removal of the necessary pressure; still, however, retaining, as might be expected, the capability of having what feeble conducting power remains, increased by the action of heat.

443.  I venture to give the following summary of the conditions of electric conduction in bodies, not however without fearing that I may have omitted some important points[A].

  [A] See now in relation to this subject, 1320—­1242.—­Dec. 1838.

444.  All bodies conduct electricity in the same manner from metals to lac and gases, but in very different degrees.

445.  Conducting power 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.