| 739 | 740 | 741 | 742 | 743 |
| 1 | 306 | 613 | 919 | 1225 |
|
shown above.
[
Footnote 23. 24: The larger of the two diagrams reproduced above
stands between these two lines, and the smaller one is sketched in
the margin. At the spot marked A Leonardo wrote corpo solare
(solar body) in the larger diagram and Sole (sun) in the smaller
one. At C luna (moon) is written and at B terra (the earth).]
Some might say that the air surrounding the moon as an element,
catches the light of the sun as our atmosphere does, and that it is
this which completes the luminous circle on the body of the moon.
Some have thought that the moon has a light of its own, but this
opinion is false, because they have founded it on that dim light
seen between the hornes of the new moon, which looks dark where it
is close to the bright part, while against the darkness of the
background it looks so light that many have taken it to be a ring of
new radiance completing the circle where the tips of the horns
illuminated by the sun cease to shine [Footnote 34: See Pl. CVIII,
No. 5.]. And this difference of background arises from the fact that
the portion of that background which is conterminous with the bright
part of the moon, by comparison with that brightness looks darker
than it is; while at the upper part, where a portion of the luminous
circle is to be seen of uniform width, the result is that the moon,
being brighter there than the medium or background on which it is
seen by comparison with that darkness it looks more luminous at that
741
Page
Quick Jump
|