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3 6 2 FRAGMEN TS OF SCIENCE.

simple attraction observed in the first instance is now re-
placed by a dual force. Repeat the experiment till you
have thoroughly observed the ends which attract and those
which repel each other.

Withdraw the magnet entirely from the vicinity of your
needle, and leave the latter freely suspended by its fibre.
Shelter it as well as you can from currents of air, and if
you have iron buttons on your coat or a steel penknife in
your pocket, beware of their action. If you work at night,
beware of iron candlesticks, or. of brass ones with iron rods
inside. Freed from such disturbances, the needle takes up
a certain determinate position. It sets its length nearly
north and south. Draw it aside from this position and let
it go. After several oscillations it will again come to it.
If you have obtained your magnet from a philosophical-in-
strument maker, you will see a mark on one of its ends.
Supposing, then, that you drew your needle along the end
thus marked, and that the eye-end of your needle was the
last to quit the magnet, you will find that the eye turns to
the south, the point of the needle turning toward the north.
Make sure of this, and do not take this statement on my
authority.

N ow take a second darning-needle like the first, and
magnetize it in precisely the same manner: freely sus-
pended it also will turn its point to the north and its eye
to the south. Your next step is to examine the action of
the two needles which you have thus magnetized upon each
other.

Take one of them in your hand, and leave the other sus-
pended; bring the eye-end of the former near the eye-end
of the latter; the suspended needle retreats : it is repelled.
Make the same experiment with the two points, you obtain
the same result, the suspended needle is repelled. Now
cause the dissimilar ends to act on each other—you have
attraction—point attracts eye and eye attracts point. Prove

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