Page 91

are struck by the heated air from the hay.
Lecture 20th.
Magnetism
Magnetism is that science which heats of
the properties of the load stone which is an
oxide of iron . It has been known to exist
for many years but its direchion proper was
not discovered until about 1300 . It has occa-
sionally been found in masses of 125 lb .
Though there is no effect without a cause yet
more than the facts that attraction exists
between the magnet and metals near it is not
known. The poles of a magnet are its extremities
that point which point which points to the north is called
the north pole and that to the south the south
pole. Opposite poles of different magnets attract
each other while like poles repel each other .
In this respect magnetism has the same prop-
-erties with electrivity. Besides the load - stone two
other metals cobalt and nickle have to some degree
magnetic properties {pross?} Fariaday has also
found magnetic properties which turn their
shorter axis north and south he calls these
dia magnetics. when a soft piece of iron
is placed within the influence of a magnet
it becomes magnetic by induction . The north
pole always induces south polarity to the
end next to it and each pole always induces