and this rapidity of molecular discharge is what we call conduction.
Conduction then is always preceded by atomic induction; and when,
through some quality of the body which Faraday does not define, the
atomic discharge is rendered slow and difficult, conduction passes
into insulation.

Though they are often obscure, a fine vein of philosophic thought
runs through those investigations. The mind of the philosopher
dwells amid those agencies which underlie the visible phenomena of
Induction and Conduction; and he tries by the strong light of his
imagination to see the very molecules of his dielectrics. It would,
however, be easy to criticise these researches, easy to show the
looseness, and sometimes the inaccuracy, of the phraseology
employed; but this critical spirit will get little good out of
Faraday. Rather let those who ponder his works seek to realise the
object he set before him, not permitting his occasional vagueness to
interfere with their appreciation of his speculations. We may see
the ripples, and eddies, and vortices of a flowing stream, without
being able to resolve all these motions into their constituent
elements; and so it sometimes strikes me that Faraday clearly saw
the play of fluids and ethers and atoms, though his previous
training did not enable him to resolve what he saw into its
constituents, or describe it in a manner satisfactory to a mind
versed in mechanics. And then again occur, I confess, dark sayings,
difficult to be understood, which disturb my confidence in this
conclusion. It must, however, always be remembered that he works at
the very boundaries of our knowledge, and that his mind habitually
dwells in the 'boundless contiguity of shade' by which that
knowledge is surrounded.