The moon's day and night, and eclipses of sun, moon and earth
How sunlight reflected from earth's water lights the moon, and when its day becomes night
Set beside ringed diagrams of the sun's and moon's orbits about the earth, these notes argue that the moon, like the earth, has day and night: day on its lit side, night on its dark side. Leonardo describes how the moon's dark side loses the sunlight reflected to it from the earth's water, and how, in a companion figure, the earth's night is left without sunlight reflected from the moon. When the moon stands in the east and the sun in the west, the day the moon had is turned wholly into night.
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The moon has day and night like the earth
Leonardo treats the darkening of sun, moon and earth as a common scheme, and holds that the moon, like the earth, has day and night: night on the part that does not shine, day on the part that does.
Sunlight reflected between earth's water and the moon
In the first orbital figure the moon's night sees the earth's light, that of its water, grow dark; the darkened water in turn sees the sun's darkening, so the moon's night loses the reverberation of the solar rays that were reflected to it from the earth.
When the moon's day is changed into night
A companion figure shows the moon's day darkened while the earth's night is left without solar rays reflected from the moon. When the moon is in the east and the sun in the west, the day the moon had while west with the sun is entirely turned into night.