Archimedes Texts

107
gin to produce those difficulties that seem in his opinion, to thwart
this new disposition of the World.

SIMPL. That disposition is not new, but very old, and that
you may see it is so, Aristotle confuteth it; and his confutations
are these: “First if the Earth moveth either in it felf about its

own Centre, or in an Excentrick Circle, it is necessary that that
same motion be violent; for it is not its natural motion, for
if it were, each of its parts would partake thereof; but each
of them moveth in a right line towards its Centre. It being
therefore violent and pteternatural, it could never be perpetu
al: But the order of the World is perpetual. Therefore, &c.
Secondly, all the other moveables that move circularly, seem
to ^{*} stay behind, and to move with more than one motion, the

Primum Mobile excepted: Whence it would be necessary that
the Earth also do move with two motions; and if that should
be so, it would inevitably follow, that mutations should be
made in the Fixed Stars, the which none do perceive; nay
without any variation, the same Stars alwayes rise from towards
the same places, and in the same places do set. Thirdly, the mo
tion of the parts is the same with that of the whole, and natural
ly tendeth towards the Centre of the Universe; and for the same
cause rest, being arrived thither. He thereupon moves the que
stion whether the motion of the parts hath a tendency to the
centre of the Universe, or to the centre of the Earth; and conclu
deth that it goeth by proper instinct to the centre of the Universe,
and per accidence to that of the Earth; of which point we largely
discoursed yesterday. He lastly confirmeth the same with a fourth
argument taken from the experiment of grave bodies, which fal
ing from on high, descend perpendicularly unto the Earthssurface;
and in the same manner Projections shot perpendicularly upwards,
do by the same lines return perpendicularly down again, though
they were shot to a very great height. All which arguments neces
sarily prove their motion to be towards the Centre of the Earth,
which without moving at all waits for, and receiveth them. He
intimateth in the last place that the Astronomers alledg other
reasons in confirmation of the same conclusions, I mean of the
Earths being in the Centre of the Universe, and immoveable;
and instanceth onely in one of them, to wit, that all the Phæ
nomena or appearances that are seen in the motions of the Stars,
perfectly agree with the position of the Earth in the Centre;
which would not be so, were the Earth seated otherwise.
The rest produced by Ptolomy and the other Astronomers, I can
give you now if you please, or after you have spoken what you
have to say in answer to these of Aristotle.”

* Restino indietzo,
which is meant
here of that moti
on which a bowl
makes when its
born by its by as to
one side or other,
and so hindered in
its direct motion.