the instrument could be perceived. Metal in the supposed peculiar state,
therefore, conducts electricity in all directions with its ordinary
facility, or, in other words, its conducting power is not sensibly altered
by it.

66. All metals take on the peculiar state. This is proved in the preceding
experiments with copper and iron (9.), and with gold, silver, tin, lead,
zinc, antimony, bismuth, mercury, &c. by experiments to be described in the
fourth part (132.), admitting of easy application. With regard to iron, the
experiments prove the thorough and remarkable independence of these
phenomena of induction, and the ordinary magnetical appearances of that
metal.

67. This state is altogether the effect of the induction exerted, and
ceases as soon as the inductive force is removed. It is the same state,
whether produced by the collateral passage of voltaic currents (26.), or
the formation of a magnet (34. 36.), or the mere approximation of a magnet
(39. 50.); and is a strong proof in addition to those advanced by M.
Ampère, of the identity of the agents concerned in these several
operations. It probably occurs, momentarily, during the passage of the
common electric spark (24.), and may perhaps be obtained hereafter in bad
conductors by weak electrical currents or other means (74. 76).

68. The state appears to be instantly assumed (12.), requiring hardly a
sensible portion of time for that purpose. The _difference_ of time between
volta-electric and magneto-electric induction, rendered evident by the
galvanometer (59.), may probably be thus explained. When a voltaic current
is sent through one of two parallel wires, as those of the hollow helix
(34.), a current is produced in the other wire, as brief in its continuance
as the time required for a single action of this kind, and which, by