o a magnet, but less
strongly than the filings themselves not acted upon by fire. For the
saffron has become totally deformate, but the heated metal acquires a
defect from the fire, and the forces in the enfeebled body are less excited
by a loadstone; and, the nature of the iron being now ruined, it is not
attracted by a loadstone.
* * * * *
CHAP. XXIIII.
A piece of Iron placed within the Orbe of a
Loadstone hangs suspended in the air, if on account
_of some impediment it cannot approach it_.
Within the magnetick orbe a piece of iron moves towards the more powerful
points of the stone, if it be not hindered by force or by the material of a
body placed between them; either it falls down from above, or tends
sideways or obliquely, or flies up above. But if the iron cannot reach the
stone on account of some obstacle, it cleaves to it and remains there, but
with a less firm and constant connection, since at greater intervals or
distances the alliance is less amicable. Fracastorio, in the eighth chapter
of his _De Sympathia_, says that a piece of iron is suspended in the air,
so that it can be moved neither up nor down, if a loadstone be placed above
which is able to draw the iron up just as much as the iron itself inclines
downwards with equal force; for thus the iron would be supported in the
air: which thing is absurd; because the force of a magnet is {92} always
the stronger the nearer it is. So that when a piece of iron is raised a
very little from the earth by the force of the magnet, it needs must be
drawn steadily on towards the magnet (if nothing else come in the way) and
cleave to it. Baptista Porta suspends a piece of iron in the air[178] (a
magnet being fixed above), and, by no very subtile process, the iron is
detained by a slender thread from its lower part, so that it cannot rise up
to the stone. The iron is raised upright by the magnet, although the magnet
does not * touch the iron, but because it is in its vicinity; but when the
whole iron on account of its greater nearness is moved by that which
erected it, immediately it hurries with a swift motion to the magnet and
cleaves to it. For by approaching the iron is more and more excited, and
the coition grows stronger.
* * * * *
CHAP. XXV.
Exaltation of the power of the Magnet.
One loadstone far surpasses another in power, since one draws iron of
almost its own weight, another
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