degree, a condition quite different to that of ordinary magnetization,
for the same rod, when magnetized to saturation under a single ordinary
magnetism, loses its evident magnetism by a few elastic torsions, as I
have already shown; but when it is magnetized under the double torsion
with its superposed magnetism, it is but slightly reduced by variations
or numerous torsions, and I have found it impossible to render this
rod again free from its double polar effects, except by strongly
remagnetizing it to saturation with a single polarity. The superposed
magnetism then becomes a single directive force, and we can then by a
few vibrations or torsions reduce the rod to its ordinary condition.

The effects of superposed magnetism and its double polarity I have
produced in a variety of ways, such as by the electro-magnetic influence
of coils, or in very soft iron simply by the directive influence of
the earth's magnetism, reversing the rod and torsions when held in
the magnetic meridian, these rods when placed magnetic west showing
distinctly the double polar effects.

It is remarkable, also, that we are enabled to superpose and obtain
the maximum effects on thin strips of iron from 1/4 to 1/2 millimeter in
thickness, while in thicker rods we have far less effect, being masked
by the comparatively neutral state of the interior, the exterior
molecules then reaching upon those of the interior, allowing them to
complete in the interior their circle of attractions.

I was anxious to obtain wires which would preserve this structure
against the destructive influence of torsion and vibrations, so that I
could constantly employ the same wires without the comparatively long
and tedious process of preparation. Soft iron soon loses the structure,
or becomes enfeebled, under the constant to and fro torsions requisite