Galilei, Galileo - Discourse concerning the natation of bodies

Galilei, Galileo, Discourse concerning the natation of bodies, 1663

None
Concordance
Figures
Thumbnails

Page concordance

Scan	Original
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50

and none light: For that the ſame would befall the Fire and Air,
if put in the Bottom of the water. And, howbeit, Ariſtotle grants
a Pulſion in the Elements, by which the Earth is reduced into a Sphe
ricall Figure, yet nevertheleſs, in his judgement, it is not ſuch that it
can remove grave Bodies from their naturall places, but rather, that
it ſend them toward the Centre, to which (as he ſomewhat obſcurely
continues to ſay,) the water principally moves, if it in the interim
meet not with ſomething that reſiſts it, and, by its Gravity, thruſts
it out of its place: in which caſe, if it cannot directly, yet at leaſt
as well as it can, it tends to the Centre: but it happens, that light
Bodies by ſuch Impulſion, do all aſcend upward: but this properly
they have by nature, as alſo, that other of ſwimming. He concludes,

laſtly, that he concurs with Archimedes in his Concluſions; but not
in the Cauſes, which he would referre to the facile and difficult Sepa
ration of the Medium, and to the predominance of the Elements, ſo
that when the Moveable ſuperates the power of the Medium; as for
example, Lead doth the Continuity of water, it ſhall move thorow it,
elſe not.

The Ancients
denved Aoſolute
Levity.

The cauſes of
Natation & Sub
merſion, accord
ing to the Peri
pateticks.

This is all that I have been able to collect, as produced againſt
Archimedes by Signor Buonamico: who hath not well obſerved the
Principles and Suppoſitions of Archimedes; which yet muſt be
falſe, if the Doctrine be falſe, which depends upon them; but is
contented to alledge therein ſome Inconveniences, and ſome Repug
nances to the Doctrine and Opinion of Ariſtotle. In anſwer to which
Objections, I ſay, firſt, That the being of Archimedes Doctrine, ſim

ply different from the Doctrine of Ariſtotle, ought not to move any
to ſuſpect it, there being no cauſe, why the Authority of this ſhould
be preferred to the Authority of the other: but, becauſe, where the
decrees of Nature are indifferently expoſed to the intellectuall eyes of
each, the Authority of the one and the other, loſeth all anthentical
neſs of Perſwaſion, the abſolute power reſiding in Reaſon; therefore
I paſs to that which he alledgeth in the ſecond place, as an abſurd con

ſequent of the Doctrine of Archimedes, namely, That water ſhould
be more grave than Earth. But I really find not, that ever Archi
medes ſaid ſuch a thing, or that it can be rationally deduced from his
Concluſions: and if that were manifeſt unto me, I verily believe, I
ſhould renounce his Doctrine, as moſt erroneous. Perhapsthis Dedu
ction of Buonamico, is founded upon that which he citeth of the Ve
ſſel, which ſwims as long as its voyd of water, but once full it ſinks to
the Bottom, and underſtanding it of a Veſſel of Earth, he infers againſt
Archimedes thus: Thou ſayſt that the Solids which ſwim, are leſs grave
than water: this Veſſell ſwimmeth: therefore, this Veſſell is leſſe grave
than water. If this be the Illation. I eaſily anſwer, granting that this
Veſſell is leſſe grave than water, and denying the other conſequence,

Text layer

Text normalization

Search