e considered as having moved relatively to each
other in opposite directions, to the amount of the tenth of an inch; i.e.
that two particles at first in combination will after the motion be the
tenth of an inch apart. Other motions which occur in the fluid will not at
all interfere with this result; for they have no power of accelerating or
retarding the electric discharge, and possess in fact no relation to it.
1652. The quantity of electricity in 25.25 grains of water is, according to
an estimate of the force which I formerly made (861.), equal to above 24
millions of charges of a large Leyden battery; or it would have kept any
length of a platina wire 1/104 of an inch in diameter red-hot for an hour
and a half (853.). This result, though given only as an approximation, I
have seen no reason as yet to alter, and it is confirmed generally by the
experiments and results of M. Pouillet[A]. According to Mr. Wheatstone's
experiments, the influence or effects of the current would appear at a
distance of 576,000 miles in a second[B]. We have, therefore, in this view
of the matter, on the one hand, an enormous quantity of power equal to a
most destructive thunder-storm appearing instantly at the distance of
576,000 miles from its source, and on the other, a quiet effect, in
producing which the power had taken an hour and a half to travel through
the tenth of an inch: yet these are the equivalents to each other, being
effects observed at the sections of one and the same current (1634.).
[A] Becquerel, Traite de l'Electricite, v. p. 278.
[B] Philosophical Transactions, 1834, p. 589.
* * * * *
1653. It is time that I should call attention to the lateral or transverse
forces of the _current_. The great things which have been achieved by
Oersted, Arago, Ampere, Davy, De la Rive, and others, and the high degree
of simplification which has been introduced into their arrangement by the
theory of Ampere, have not only done their full service in advancing most
rapidly this branch of knowledge, but have secured to it such attention
that there is no necessity for urging on its pursuit. I refer of course to
magnetic action and its relations; but though this is the only recognised
lateral action of the current, there is great reason for believing that
others exist and would by their discovery reward a close search for them
(951.).
1654. The magnetic or transverse action of the current seems to b
|