Page:A history of the theories of aether and electricity. Whittacker E.T. (1910).pdf/228

From Wikisource
Jump to navigation Jump to search
This page has been proofread, but needs to be validated.
208
Faraday.

coatings connected with any continued source of the two electrical powers, the ice will charge like a Leyden arrangement, presenting a case of common induction, but no current will pass. If the ice be liquefied, the induction will now fall to a certain degree, because a current can now pass; but its passing is dependent upon a peculiar molecular arrangement of the particles consistent with the transfer of the elements of the electrolyte in opposite directions As, therefore, in the electrolytic action, induction appeared to be the first step, and decomposition the second (the power of separating these steps from each other by giving the solid or fluid condition to the electrolyte being in our hands); as the induction was the same in its nature as that through air, glass, wax, &c., produced by any of the ordinary means; and as the whole effect in the electrolyte appeared to be an action of the particles thrown into a peculiar or polarized state, I was glad to suspect that common induction itself was in all cases an action of contiguous particles, and that electrical action at a distance (i.e., ordinary inductive action) never occurred except through the influence of the intervening matter."

Thus at the root of Faraday's conception of electrostatic induction lay this idea that the whole of the insulating medium through which the action takes place is in a state of polarization similar to that which precedes decomposition in an electrolyte. "Insulators," he wrote,[1] "may be said to be bodies whose particles can retain the polarized state, whilst conductors are those whose particles cannot be permanently polarized."

The conception which he at this time entertained of the polarization may be reconstructed from what he had already written concerning electrolytes. He supposed[2] that in the ordinary or unpolarized condition of a body, the molecules consist of atoms which are bound to each other by the forces of chemical affinity, these forces being really electrical in their nature; and that the same forces are exerted, though to a less

  1. Exp. Res., § 1338.
  2. This must not be taken to be more than an idea which Faraday mentioned as present to his mind. He declined as yet to formulate a definite hypothesis.