CHAP. IIII.
Which pole of the stone is the Boreal: & how it is
distinguished from the austral.
ne pole of the earth turns toward the
constellation of the Cynosure, and constantly regards a fixed point in the heaven (except so far as it changes by the
fixed stars being shifted in longitude, which motion we recognize as existing in the earth, as we shall hereafter prove):
While the other pole turns to the opposite face of heaven, unknown to the ancients, now visible on long voyages, and
adorned with multitudinous stars: In the same way the loadstone has the property and power of directing itself North and
South (the earth herself consenting and contributing force thereto) according to the conformation of nature, which
arranges the movements of the stone towards its native situation. Which thing is proved thus: Place a magnetick stone
(after finding the poles) in a round wooden vessel, a Bowl or dish, at the same time place it together with the vessel
(like a sailor in a skiff) upon water in some large vessel or cistern, so that it may be able to float freely in the
middle, nor touch the edge of it, and where the air is not disturbed by winds, which would thwart the natural movement of
the stone. Hereupon the stone placed as it were in a ship, in the middle of the surface of the still and unruffled water,
will at once put itself in motion along with the vessel that carries it, and revolve circularly, until its austral pole
points to the north, and its boreal pole to the south. For it reverts from the contrary position to the poles: and
although by the first too-vehement impulse it over-passes the poles; yet after returning again and again, it rests at
length at the poles, or at the meridian (unless because of local reasons it is diverted some little from those points, or
from the meridional line, by some sort of variation66, the cause of which we
will hereafter state). However often you move it away from its place, so often by virtue of nature's noble dower does it
seek again those sure and determined goals; and this is so, not only if the poles have been
disposed in the vessel evenly with the plane of the horizon, but also in the case of one pole, whether austral or boreal,
being raised in the vessel ten, or twenty, or thirty, or fifty or eighty degrees, above * the plane of the horizon, or lowered beneath it:
Still you shall see the boreal part of the stone seek the south, and the austral part seek the north; So much so that if
the pole of the stone shall be only one degree distant from the Zenith and highest point of the heaven, in the case of a
spherical stone, the whole stone revolves until the pole occupies its own site; though not in the absolutely direct line,
it will yet tend toward those parts, and come to rest in the meridian of the directive action. With a like impulse too it
is borne if the austral pole have been raised toward the upper quarters, the same as if the Boreal had been exalted above
the Horizon. But it is always to be noted that, though there are various kinds of unlikeness in the stones, and one
loadstone may far surpass another in virtue and efficiency; yet all hold to the same limits, and are borne toward the
same points. Further it is to be remembered * that all who before our time wrote of the poles
of the stone, and all the craftsmen and navigators, have been very greatly in error in considering the part of the stone
which tended to the north as the north pole of the stone, and that which verged toward the south, the south pole, which
we shall hereafter prove to be false. So badly hitherto hath the whole magnetick philosophy been cultivated, even as to
its foundation principles.