er than in
_the other parts intermediate between the aequator and the pole;_
and on the proportion of forces of the coition in
_various parts of the earth and of the terrella_.
Observation has already been made that the highest power of alluring exists
in the pole, and that it is weaker and more languid in the parts adjacent
to the aequator. And as this is apparent in the declination, because that
disponent and rotational virtue has an augmentation as one proceeds from
the Aequator towards the poles: so also the coition of magneticks grows
increasingly fresh by the same steps, and in the same proportion. For in
the parts more remote from the poles the loadstone does not draw magneticks
straight down towards its own viscera; but they tend obliquely and they
allure obliquely. For as the smallest chords in a circle differ from the
diameter, so much do the forces of attracting differ between themselves in
different parts of the terrella. {82} For since attraction is coition
towards a body, but magneticks run together by their versatory tendency, it
comes about that in the diameter drawn from pole to pole the body appeals
directly, but in other places less directly. So the less the magnetick is
turned toward the body, the less, and the more feebly, does it approach and
adhaere. [Illustration] Just as if A B were the poles and a bar of iron or
a magnetick fragment C is allured at the part E; yet the end laid hold of
does not tend towards the centre of the loadstone, but verges obliquely
towards the pole; and a chord drawn from that end obliquely as the
attracted body tends is short; therefore it has less vigour and likewise
less inclination. But as a greater chord proceeds from a body at F, so its
action is stronger; at G still longer; longest at A, the pole (for the
diameter is the longest way) to which all the parts from all sides bring
assistance, in which is constituted, as it were, the citadel and tribunal
of the whole province, not from any worth of its own, but because a force
resides in it contributed from all the other parts, just as all the
soldiers bring help to their own commander. Wherefore also a slightly
longer stone attracts more than a spherical one, since the length from pole
to pole is extended, even if the stones are both from the same mine and of
the same weight and size. The way from pole to pole is longer in a longer
stone, and the forces brought together from other parts are not so
scattered as in a ro
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