1which being of a ſpherical figure, if its ſuperficies were ſmooth, as
this paper, the parts of its hemiſphere illuminated by the Sun,
which are towards its extremity, would receive much leſs light,
than the middle parts; the rays falling upon them moſt obliquely,
and upon theſe at right angles; whereupon at the time of full
Moon, when we ſee almoſt its whole Hemiſphere illuminated, the
parts towards the midſt, would ſhew themſelves to us with more
ſplendor, than thoſe others towards the circumference: which is
not ſo in effect. Now the face of the Moon being repreſented
to me full of indifferent high mountains, do not you ſee how their
tops and continuate ridges, being elevated above the convexity of
the perfect ſpherical ſuperficies, come to be expoſed to the view
of the Sun, and accommodated to receive its rays much leſs
liquely, and conſequently to appear as luminous as the reſt?
this paper, the parts of its hemiſphere illuminated by the Sun,
which are towards its extremity, would receive much leſs light,
than the middle parts; the rays falling upon them moſt obliquely,
and upon theſe at right angles; whereupon at the time of full
Moon, when we ſee almoſt its whole Hemiſphere illuminated, the
parts towards the midſt, would ſhew themſelves to us with more
ſplendor, than thoſe others towards the circumference: which is
not ſo in effect. Now the face of the Moon being repreſented
to me full of indifferent high mountains, do not you ſee how their
tops and continuate ridges, being elevated above the convexity of
the perfect ſpherical ſuperficies, come to be expoſed to the view
of the Sun, and accommodated to receive its rays much leſs
liquely, and conſequently to appear as luminous as the reſt?
The more oblique
Rayes illuminate
leß, and why.
Rayes illuminate
leß, and why.
SAGR. All this I well perceive: and if there are ſuch
tains, its true, the Sun will dart upon them much more directly
than it would do upon the inclination of a polite ſuperficies: but
it is alſo true, that betwixt thoſe mountains all the valleys would
become obſcure, by reaſon of the vaſt ſhadows, which in that
time would be caſt from the mountains, whereas the parts towards
the middle, though full of valleys and hills, by reaſon they have
the Sun elevated, would appear without ſhadow, and therefore
more lucid by far than the extreme parts, which are no leſs
ſed with ſhadow than light, and yet we can perceive no ſuch
rence.
tains, its true, the Sun will dart upon them much more directly
than it would do upon the inclination of a polite ſuperficies: but
it is alſo true, that betwixt thoſe mountains all the valleys would
become obſcure, by reaſon of the vaſt ſhadows, which in that
time would be caſt from the mountains, whereas the parts towards
the middle, though full of valleys and hills, by reaſon they have
the Sun elevated, would appear without ſhadow, and therefore
more lucid by far than the extreme parts, which are no leſs
ſed with ſhadow than light, and yet we can perceive no ſuch
rence.
SIMPL. I was ruminating upon the like difficulty.
SALV. How much readier is Simplicius to apprehend the
jections which favour the opinions of Ariſtotle, than their
ons? I have a kind of ſuſpition, that he ſtrives alſo ſometimes to
diſſemble them; and in the preſent caſe, he being of himſelf able
to hit upon the doubt, which yet is very ingenious, I cannot
lieve but that he alſo was adviſ'd of the anſwer; wherefore I will
attempt to wreſt the ſame (as they ſay) out of his mouth.
fore tell me, Simplicius, do you think there can be any ſhadow,
where the rays of the Sun do ſhine?
jections which favour the opinions of Ariſtotle, than their
ons? I have a kind of ſuſpition, that he ſtrives alſo ſometimes to
diſſemble them; and in the preſent caſe, he being of himſelf able
to hit upon the doubt, which yet is very ingenious, I cannot
lieve but that he alſo was adviſ'd of the anſwer; wherefore I will
attempt to wreſt the ſame (as they ſay) out of his mouth.
fore tell me, Simplicius, do you think there can be any ſhadow,
where the rays of the Sun do ſhine?
SIMPL. I believe, nay I am certain that there cannot; for that
it being the grand luminary, which with its rays driveth away
neſs, it is impoſſible any tenebroſity ſhould remain where it
eth; moreover, we have the definition, that Tenebræ ſunt
tio luminis.
it being the grand luminary, which with its rays driveth away
neſs, it is impoſſible any tenebroſity ſhould remain where it
eth; moreover, we have the definition, that Tenebræ ſunt
tio luminis.
SALV. Therefore the Sun, beholding the Earth, Moon or
ther opacous body, never ſeeth any of its ſhady parts, it not
ving any other eyes to ſee with, ſave its rays, the conveyers of
light: and conſequently, one ſtanding in the Sun would never
ſee any thing of umbrage, foraſmuch as his viſive rays would ever
ther opacous body, never ſeeth any of its ſhady parts, it not
ving any other eyes to ſee with, ſave its rays, the conveyers of
light: and conſequently, one ſtanding in the Sun would never
ſee any thing of umbrage, foraſmuch as his viſive rays would ever
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