|Galilei, Galileo Dialogues on two world systems 1661, tr. Salusbury, Thomas|
remotiores, in minori circulo feruntur? [scilicet:] Why are
those near the Æquinoctial carried about in a greater circle, and
those which are remote in a lesser?
SALV. To imitate the starry Sphere, in which those nearest
to the Æquinoctial, move in greater circles, than the more re
SIMP. Quarè Pila eadem sub Æquinoctiali tota circa centrum
terr æ, ambitu maximo, celeritate incredibili; sub Polo verò circa
centrum proprium, gyro nullo, tarditate supremâ volveretur?
[That is:] Why is the same ball under the Æquinoctial wholly
turned round the centre of the Earth in the greatest circumfe
rence, with an incredible celerity; but under the Pole about its
own centre, in no circuite, but with the ultimate degree of tar
SALV. To imitate the stars of the Firmament, that would do
the like if they had the diurnal motion.
SIMP. Quare eadem res, pila v. g. plumbea, si semel terram
circuivit, descripto circulo maximo, eandem ubique non circum
migret secundùm circulum maximum, sed translata extra Æquino
ctialem in circulis minoribus agetur? [Which speaketh thus:]
Why doth not the same thing, as for example, a ball of lead
turn round every where according to the same great circle, if once
describing a great circle, it hath incompassed the Earth, but being
removed from the Æquinoctial, doth move in lesser circles?
SALV. Because so would, nay, according to the doctrine of
Ptolomey, so have some fixed stars done, which once were very
near the Æquinoctial, and described very vast circles, and now that
they are farther off, describe lesser.
SAGR. If I could now but keep in mind all these fine no
tions, I should think that I had made a great purchase; I must
needs intreat you, Simplicius, to lend me this Book, for there can
not chuse but be a sea of rare and ingenious matters contained in
SIMP. I will present you with it.
SAGR. Not so, Sir; I would not deprive you of it: but are
the Queries yet at an end?
SIMP. No Sir; hearken therefore. Si latio circularis gra
vibus & levibus est naturalis, qualis est ea quæ fit secundùm line
am rectam? Nam si naturalis, quomodo & is motus qui circum est,
naturalis est, cùm specie differat à recto? Si violentus, quî fit, ut
missile ignitum sursùm evolans scintillosum caput sursùm à terrâ,
non autem circum volvatur, &c. [Which take in our idiom:] If
a circular lation is natural to heavy and light things, what is that
which is made according to a right line? For if it be natural, how
then is that motion which is about the centre natural, seeing it