ron draws away a piece of iron from a terrella, so is it also
with a minute loadstone and a lesser terrella, though weaker in strength.

[Illustration]

The piece of iron C comes into conjunction with the terrella A, and the
vigour in it is magnetically exalted and excited, both in the adjoining end
and in the other also which is turned away through {103} its conjunction
with the terrella. The end that is turned away also conceives vigour from
the loadstone B; likewise the pole D of that loadstone is powerful on
account of its suitable aspect and the nearness of the pole E of the
terrella. Several causes therefore concur why the piece of iron C should
cleave to the terrella B, to which it is joined more firmly than to the
terrella A; the vigour excited in the rod, the vigour also excited in the
stone B, and the strength implanted in B concur; therefore D is more firmly
cemented magnetically with C than E with C.

But if you were to turn the vertex F round to the iron C, C would not
adhaere to F as formerly to D; for stones so arranged being within the orbe
of virtue are placed contrary to natural order; wherefore F does not
receive power from E.

Two loadstones or excited pieces of iron, duly cohaering, fly * asunder on
the approach of another more powerful loadstone or magnetized piece of
iron. Because the new-comer repels the other with its opposing face, and
dominates it, and ends the relationship of the two which were formerly
joined. So the forces of the other are lessened and succumb; but if it
conveniently could, being diverted of its association with the weaker, and
rolling round, it would turn about to the stronger. Wherefore also
magnetick bodies suspended in the air fall when a loadstone is brought near
them with an opposing face, not (as Baptista Porta teaches) because the
faculty of both those which were joined before grows faint and torpid, for
no face can be hostile to both the ends which cohaere, but to one only; and
when the stronger loadstone, coming fresh with opposing face, impels this
further from it, it is put to flight by the friendly reception of the
former.

* * * * *

CHAP. XXXIII.

On the Varying Ratio of Strength, and of the Motion
_of coition, within the orbe of virtue_.

Should a very large weight, which at a very small distance is drawn towards
a loadstone, be divided into ever so many equal parts, and should the
radius of the orbe of magnetick att