743 | 744 | 745 | 746 | 747 |
1 | 306 | 613 | 919 | 1225 |
reflected in a convex body takes up but a small portion of that
body, as is proved in perspective [Footnote 18: come e provato.
This alludes to the accompanying diagram.]. The third reason is that
when the moon is full, it only faces half the hemisphere of the
illuminated earth, on which only the ocean and other waters reflect
bright light, while the land makes spots on that brightness; thus
half of our earth would be seen girt round with the brightness of
the sea lighted up by the sun, and in the moon this reflection would
be the smallest part of that moon. Fourthly, a radiant body cannot
be reflected from another equally radiant; therefore the sea, since
it borrows its brightness from the sun,--as the moon does--, could
not cause the earth to be reflected in it, nor indeed could the body
of the sun be seen reflected in it, nor indeed any star opposite to
it.
9
06.
If you keep the details of the spots of the moon under observation
you will often find great variation in them, and this I myself have
proved by drawing them. And this is caused by the clouds that rise
from the waters in the moon, which come between the sun and those
waters, and by their shadow deprive these waters of the sun's rays.
Thus those waters remain dark, not being able to reflect the solar
body.
9
07.
745
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