Platinum Water
Many ores and Alcohol
salts of the Tellurium
above metals Selenium
Oxygen Sulphur
Thallium
Hydrogen
Air

We have theories of magnetism that reduce it to a phenomenon of
electricity, though we are ignorant of the real nature of both. If
we take a thin bar magnet and break it in two, we find that we
have now two shorter magnets, each with its "north" and "south"
poles, that is to say, poles of the same kind as the south and
north--magnetic poles of the earth. If we break each of these
again, we get four smaller magnets, and we can repeat the process
as often as we like. It is supposed, therefore, that every atom of
the bar is a little magnet in itself having its two opposite
poles, and that in magnetising the bar we have merely partially
turned all these atoms in one direction, that is to say, with
their north poles pointing one way and their south poles the other
way, as shown in figure 27. The polarity of the bar only shows
itself at the ends, where the molecular poles are, so to speak,
free.

There are many experiments which support this view. For example,
if we heat a magnet red hot it loses its magnetism, perhaps
because the heat has disarranged the particles and set the
molecular poles in all directions. Again, if we magnetise a piece
of soft iron we can destroy its magnetism by striking it so as to