Consider a permanent magnet a (Fig. 15), free to turn on an axis in the direction of the arrow. If there be other free magnets, b and c, in line, they will assume such positions that their similar poles all point one way. Let a be twisted to a position at right angles, then b will turn, but in the opposite direction, and c in similar. That is, if a turn in the direction of the hands of a clock, b and c will turn in opposite directions. These are simply the
observed movements of large magnets. Imagine that these magnets be reduced to atomic dimensions, yet retaining their magnetic qualities, poles and fields. Would they not evidently move in the same way and for the same reason? If it be true, that a magnet field always so acts upon another as to tend by rotation to set the latter into a certain position, with reference to the stress in that field, then, wherever there is a changing magnetic field, there the atoms are being adjusted by it.
Fig. 16.
Suppose we have a line of magnetic needles free to turn, hundreds or thousands of them, but disarranged. Let a strong magnetic field be produced at one end of the line. The field would be strongest and best conducted along the magnet line, but every magnet in the line would be compelled to rotate, and if the first were kept rotating, the rotation
would be kept up along the whole line. This would be a mechanical illustration of how an electric current travels in a conductor. The rotations are of the atomic sort, and are at right angles to the direction of the conductor.
That which makes the magnets move is inductive magnetic ether stress, but the advancing motion represents mechanical energy of rotation, and it is this motion, with the resulting friction, which causes the heat in a conductor.
What is important to note is, that the action in the ether is not electric action, but more properly the result of electro-magnetic action. Whatever name be given to it, and however it comes about, there is no good reason for calling any kind of ether action electrical.
Electric action, like magnetic action, begins and ends in matter. It is subject to transformations into thermal and mechanical actions, also into ether stress—right-handed or left-handed—which, in turn, can similarly affect other matter, but with opposite polarities.