electro magnet and armature is shown in Fig. 6. The alternating current
coils, C C', are wound upon an iron wire bundle bent into U form, and
opposite its poles is placed a pair of thick copper disks, B B', which
are attracted and repelled, but with an excess of repulsion depending on
their form, thickness, etc.

[Illustration: FIG. 11.]

If the iron core takes the form of that shown by I I, Fig. 7, such as a
cut ring with the coil, C, wound thereon, the insertion of a heavy
copper plate, B, into the slot or divided portion of the ring will be
opposed by a repulsive effort when alternating currents pass in C. This
was the first form of device in which I noticed the phenomenon of
repulsive preponderance in question. The tendency is to thrust the
plate, B, out of the slot in the ring excepting only when its center is
coincident with the magnetic axis joining the poles of the ring between
which B is placed.

If the axes of the conductors, Fig. 5, are not coincident, but
displaced, as in Fig. 8, then, besides a simple repulsion apart, there
is a lateral component or tendency, as indicated by the arrows. Akin to
this is the experiment illustrated in Fig. 9. Here the closed conductor,
B, is placed with its plane at right angles to that of C, wound on a
wire bundle. The part, B, tends to move toward the center of the coil,
C, so that its axis will be in the middle plane of C, transverse to the
core, as indicated by the dotted line. This leads us at once to another
class of actions, i.e., deflective actions.

[Illustration: FIG. 12.]