[Footnote 29: The heading _alberi vicini_ (trees at a short
distance) is in the original manuscript written in the margin.] When
the trees are situated between the sun and the eye, beyond the
shadow which spreads from their centre, the green of their leaves
will be seen transparent; but this transparency will be broken in
many places by the leaves and boughs in shadow which will come
between you and them, or, in their upper portions, they will be
accompanied by many lights reflected from the leaves.
454.
The trees of the landscape stand out but little from each other;
because their illuminated portions come against the illuminated
portions of those beyond and differ little from them in light and
shade.
455.
Of trees seen from below and against the light, one beyond the other
and near together. The topmost part of the first will be in great
part transparent and light, and will stand out against the dark
portion of the second tree. And thus it will be with all in
succession that are placed under the same conditions.
Let _s_ be the light, and _r_ the eye, _c d n_ the first tree, _a b
c_ the second. Then I say that _r_, the eye, will see the portion _c
f_ in great part transparent and lighted by the light _s_ which
falls upon it from the opposite side, and it will see it, on a dark
ground _b c_ because that is the dark part and shadow of the tree _a
b c_.
But if the eye is placed at _t_ it will see _o p_ dark on the light
background _n g_.
Of the transparent and shadowy parts of trees, that which is nearest
to you is the darkest.
456.
That part of a tree which has shadow for background, is all of one
tone, and wherever the trees or branches are thickest they will be
darkest, because there are no little intervals of air. But where the
boughs lie against a background of other boughs, the brighter parts
are seen lightest and the leaves lustrous from the sunlight falling
on them.
457.
In the composition of leafy trees be careful not to repeat too often
the same colour of one tree against the same colour of another
[behind it]; but vary it with a lighter, or a darker, or a stronger
green.
On the treatment of light for landscapes (458-464).
458.
The landscape has a finer azure [tone] when, in fine weather the sun
is at noon than at any other time of the day, because the air is
purified of moisture; and looking at it under that aspect you will
see the trees of a beautiful green at the outside and the shadows
dark towards the middle; and in the remoter distance the atmosphere
which comes between you and them looks more beautiful when there is
something dark beyond. And still the azure is most beautiful. The
objects seen from the side on which the sun shines will not show you
their shadows. But, if you are lower than the sun, you can see what
is not seen by the sun and that will be all in shade. The leaves of
the trees, which come between you and the sun are of two principal
colours which are a splendid lustre of green, and the reflection of
the atmosphere which lights up the objects which cannot be seen by
the sun, and the shaded portions which only face the earth, and the
darkest which are surrounded by something that is not dark. The
trees in the landscape which are between you and the sun are far
more beautiful than those you see when you are between the sun and
them; and this is so because those which face the sun show their
leaves as transparent towards the ends of their branches, and those
that are not transparent--that is at the ends--reflect the light;
and the shadows are dark because they are not concealed by any
thing.
The trees, when you place yourself between them and the sun, will
only display to you their light and natural colour, which, in
itself, is not very strong, and besides this some reflected lights
which, being against a background which does not differ very much
from themselves in tone, are not conspicuous; and if you are lower
down than they are situated, they may also show those portions on
which the light of the sun does not fall and these will be dark.
In the Wind.
But, if you are on the side whence the wind blows, you will see the
trees look very much lighter than on the other sides, and this
happens because the wind turns up the under side of the leaves,
which, in all trees, is much whiter than the upper sides; and, more
especially, will they be very light indeed if the wind blows from
the quarter where the sun is, and if you have your back turned to
it.
[Footnote: At _S_, in the original is the word _Sole_ (sun) and at
_N parte di nuvolo_ (the side of the clouds).]
459.
When the sun is covered by clouds, objects are less conspicuous,
because there is little difference between the light and shade of
the trees and of the buildings being illuminated by the brightness
of the atmosphere which surrounds the objects in such a way that the
shadows are few, and these few fade away so that their outline is
lost in haze.
460.