the Queen of England, was already separated from the original MS. at the time when the Vatican copy was made.]
Light and shade on clouds (474-477).
474.
Describe how the clouds are formed and how they dissolve, and what cause raises vapour.
475.
The shadows in clouds are lighter in proportion as they are nearer to the horizon.
[Footnote: The drawing belonging to this was in black chalk and is totally effaced.]
476.
When clouds come between the sun and the eye all the upper edges of their round forms are light, and towards the middle they are dark, and this happens because towards the top these edges have the sun above them while you are below them; and the same thing happens with the position of the branches of trees; and again the clouds, like the trees, being somewhat transparent, are lighted