That the Earth moves circularly.
If then the philosophers of the common sort, with an unspeakable absurdity,
imagine the whole heaven and the vast extent of the universe to rotate in a
whirl, it yet remains that the earth performs a diurnal change. For in no
third way can the apparent revolutions be explained. This day, then, which
is called natural, is a revolution of some meridian of the Earth from Sun
to Sun. It revolves indeed in an entire course, from a fixed star round to
that star again. Those bodies which in nature are moved with a circular,
æquable and constant motion, are furnished, in their parts, with various
boundaries. But the Earth is not a Chaos nor disordered mass; but by reason
of its astral virtue, it has boundaries which subserve the circular motion,
poles not mathematical, an æquator not devised by imagination, meridians
also and parallels; all of which we find permanent, certain and natural in
the Earth: which by numerous experiments the whole magnetick philosophy
sets forth. For in the earth there are poles set in fixed bounds, and at
them the verticity mounts up on either side from the plane of the Earth's
æquator, with forces which are mightier and præpotent from the common
action of the whole; and with these poles the diurnal revolution is in
agreement. But in no turnings-about of bodies, in none of the motions of
the planets are there to be recognized, beheld, or assured to us by any
reasoning any sensible or natural poles in the firmament, or in any
_Primum_ {221} _Mobile_; but those are the conception of an unsettled
imagination. Wherefore we, following an evident, sensible and tested cause,
do know that the earth moves on its own poles, which are apparent to us by
many magnetick demonstrations. For not only on the ground of its constancy,
and its sure and permanent position, is the Earth endowed with poles and
verticity: for it might be directed toward other parts of the universe,
toward East or West or some other region. By the wondrous wisdom then of
the Builder forces, primarily animate, have been implanted in the Earth,
that with determinate constancy the Earth may take its direction, and the
poles have been placed truly opposite[246], that about them as the termini,
as it were, of some axis, the motion of diurnal turning might be performed.
But the constancy of the poles is regulated by the primary soul. Wherefore,
for the Earth's good, the collimations of her verticities do not
continually regard a definite point of the firmament and of the visible
heaven. For changes of the æquinoxes take place from a certain deflection
of the Earth's axis; yet in regard to that deflection, the Earth has a
constancy of motion [Illustration] derived from her own forces. The Earth,
that she may turn herself about in a diurnal revolution, leans on her
poles. For since at A and B there is constant verticity, and the axis is
straight; at C and D (the æquinoctial line) the parts are free, the whole
forces on either side being spread out from the plane of the æquator toward
the poles, in æther which is free from renitency, or else in a void; and A
and B remaining constant, C revolves toward D both from innate conformity
and aptitude, and for necessary good, and the avoidance of evil; but being
chiefly moved forward by the diffusion of the solar orbes of virtues, and
by their lights. And 'tis borne around, not upon a new and strange course,
but (with the {222} tendency common to the rest of the planets) it tends
from West to East. For all planets have a like motion Eastward according to
the succession of the signs, whether Mercury and Venus revolve beneath the
Sun, or around the Sun. That the Earth is capable of and fitted for moving
circularly its parts show, which when separated from the whole are not only
borne along with the [Illustration] straight movement taught by the
Peripateticks, but rotate also. A loadstone fixed in a wooden vessel is
placed on water so as to swim freely, turn itself, and float about. If the
pole B of the loadstone be set contrary to nature toward the South, F, the
Terrella is turned about its own centre with a circular motion in the plane
of the Horizon, toward the North, E, where it rests, not at C or D. So does
a small stone if only of four ounces; it has the same motion also and just
as quick, if it were a strong magnet of one hundred pounds. The largest
magnetical mountain will possess the same turning-power also, if launched
in a wide river or deep sea: and yet a magnetick body is much more hindered
by water than the whole Earth is by the æther. The whole Earth would do the
same, if the Boreal pole were to be diverted from its true direction; for
the Boreal pole would run back with the circular motion of the whole around
the centre toward the Cynosure. But this motion by which the parts
naturally settle themselves in their own {223} resting-places is no other
than circular. The whole Earth regards the Cynosure with her pole according
to a steadfast law of her nature: and thus each true part of it seeks a
like resting-place in the world, and is moved circularly toward that
position. The natural movements of the whole and of the parts are alike:
wherefore when the parts are moved in a circle, the whole also has the
potency of [Illustration] moving circularly. A sphærical loadstone placed
in a vessel on water moves circularly around its centre (as is manifest) in
the plane of the Horizon, into conformity[247] with the earth.
So also it would move in any other great circle if it could be free; as in
the declination instrument, a circular motion takes place in the meridian
(if there were no variation), or, if there should be some variation, in a
great circle drawn from the Zenith through the point of variation on the
horizon. And that circular motion of the magnet to its own just and natural
position shows that the whole Earth is fitted and adapted, and is
sufficiently furnished with peculiar forces for diurnal circular motion. I
omit what Peter Peregrinus[248] constantly affirms, that a terrella
suspended above its poles on a meridian moves circularly, making an entire
revolution in 24 hours: which, however, it has not happened to ourselves as
yet to see; and we even doubt this motion on account of the weight of the
stone itself, as well as because the whole Earth, as she is moved of
herself, so also is she propelled by other stars: and this does not happen
in proportion (as it does in the terrella) {224} in every part. The Earth
is moved by her own primary form and natural desire, for the conservation,
perfection, and ordering of its parts, toward things more excellent: and
this is more likely than that the fixed stars, those luminous globes, as
well as the Wanderers, and the most glorious and divine Sun, which are in
no way aided by the Earth, or renewed, or urged by any virtue therein,
should circulate aimlessly around the Earth, and that the whole heavenly
host should repeat around the Earth courses never ending and of no profit
whatever to the stars. The Earth, then, which by some great necessity, even
by a virtue innate, evident, and conspicuous, is turned circularly about
the Sun, revolves; and by this motion it rejoices in the solar virtues and
influences, and is strengthened by its own sure verticity, that it should
not rovingly revolve over every region of the heavens. The Sun (the chief
agent in nature) as he forwards the courses of the Wanderers, so does he
prompt this turning about of the Earth by the diffusion of the virtues of
his orbes, and of light. And if the Earth were not made to spin with a
diurnal revolution, the Sun would ever hang over some determinate part with
constant beams, and by long tarriance would scorch it, and pulverize it,
and dissipate it, and the Earth would sustain the deepest wounds; and
nothing good would issue forth; it would not vegetate, it would not allow
life to animals, and mankind would perish. In other parts, all things would
verily be frightful and stark with extreme cold; whence all high places
would be very rough, unfruitful, inaccessible, covered with a pall of
perpetual shades and eternal night. Since the Earth herself would not
choose to endure this so miserable and horrid appearance on both her faces,
she, by her magnetick astral genius, revolves in an orbit, that by a
perpetual change of light there may be a perpetual alternation of things,
heat and cold, risings and settings, day and night, morn and eve, noon and
midnight. Thus the Earth seeks and re-seeks the Sun, turns away from him
and pursues him, by her own wondrous magnetick virtue. Besides, it is not
only from the Sun that evil would impend, if the Earth were to stay still
and be deprived of solar benefit; but from the Moon also serious dangers
would threaten. For we see how the ocean rises and swells beneath certain
known positions of the Moon: And if there were not through the daily
rotation of Earth a speedy transit of the Moon, the flowing sea would be
driven above its level into certain regions, and many shores would be
overwhelmed with huge waves. In order then that Earth may not perish in
various ways, and be brought to confusion, she turns herself about by
magnetick and primary virtue: and the like motions exist also in the rest
of the Wanderers, urged specially by the movement and light of other
bodies. For the Moon also turns herself about in a monthly course, to
receive in succession the Sun's beams in which she, like the Earth, {225}
rejoices, and is refreshed: nor could she endure them for ever on one
particular side without great harm and sure destruction. Thus each one of
the moving globes is for its own safety borne in an orbit either in some
wider circle, or only by a rotation of its body, or by both together. But
it is ridiculous for a man a philosopher to suppose that all the fixed
stars and the planets and the still higher heavens revolve to no other
purpose, save the advantage of the Earth. It is the Earth, then, that
revolves, not the whole heaven, and this motion gives opportunity for the
growth and decrease of things, and for the generating of things animate,
and awakens internal heat for the bringing of them to birth. Whence matter
is quickened for receiving forms; and from the primary rotation of the
Earth natural bodies have their primary impetus and original activity. The
motion then of the whole Earth is primary, astral, circular, around its own
poles, whose verticity arises on both sides from the plane of the æquator,
and whose vigour is infused into opposite termini, in order that the Earth
may be moved by a sure rotation for its good, the Sun also and the stars
helping its motion. But the simple straight motion downwards of the
Peripateticks is a motion of weight, a motion of the aggregation of
disjoined parts, in the ratio of their matter, along straight lines toward
the body of the Earth: which lines tend the shortest way toward the centre.
The motions of disjoined magnetical parts of the Earth, besides the motion
of aggregation, are coition, revolution, and the direction of the parts to
the whole, for harmony of form, and concordancy.
* * * * *