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In trees that are illuminated [both] by the sun and the atmosphere
and that
have leaves of a dark colour, one side will be illuminated
by the atmosphere
[only] and in consequence of this light will tend
to blueness, while on the
other side they will be illuminated by the
atmosphere and the sun; and the
side which the eye sees illuminated
by the sun will reflect light.
The trees and plants which are most thickly branched with slender
branches
ought to have less dark shadow than those trees and plants
which, having
broader leaves, will cast more shadow.
The shadows of trees placed in a landscape do not display themselves
in the
same position in the trees on the right hand and those on the
left; still
more so if the sun is to the right or left. As is proved
by the 4th which
says: Opaque bodies placed between the light and
the eye display themselves
entirely in shadow; and by the 5th: The
eye when placed between the opaque
body and the light sees the
opaque body entirely illuminated. And by the 6th:
When the eye and
the opaque body are placed between darkness and light, it
will be
seen half in shadow and half in light.
Of the plants which take a shadow from the plants which spring among
them,
those which are on this side [in front] of the shadow have the
stems lighted
up on a background of shadow, and the plants on which
the shadows fall have
their stems dark on a light background; that
is on the background beyond the
shadow.
Of the trees which are between the eye and the light the part in
front will
be light; but this light will be broken by the
ramifications of transparent
leaves--being seen from the under
side--and lustrous leaves--being seen from
the upper side; and the
background below and behind will be dark green, being
in shadow from
the front portion of the said tree. This occurs in trees
placed
above the eye.
Landscapes should be represented so that the trees may be half in
light and
half in shadow; but it is better to do them when the sun
is covered with
clouds, for then the trees are lighted by the
general light of the sky, and
the general darkness of the earth. And
then they are darkest in certain parts
in proportion as those parts
are nearest to the middle of the tree and to the
earth.
When the sun is in the east the trees to the South and to the North
have
almost as much light as shadow. But a greater share of light in
proportion as
they lie to the West and a greater share of shadow in
proportion as they lie
to the East.
If the sun is in the East the verdure of the meadows and of other
small
plants is of a most beautiful green from being transparent to
the sun; this
does not occur in the meadows to the West, and in
those to the South and
North the grass is of a moderately brilliant
green.
When the sun is in the East the trees seen towards the East will
have the
light which surrounds them all round their shadows,
excepting on the side
towards the earth; unless the tree has been
pruned [below] in the past year.
And the trees to the South and
North will be half in shade and half in light,
and more or less in
shade or in light in proportion as they are more or less
to the East
or to the West.
The [position of] the eye above or below
varies the shadows and
lights in trees, inasmuch as the eye placed above sees
the tree with
the little shadow, and the eye placed below with a great deal
of
shadow.
The colour of the green in plants varies as much as their
species.
To represent a landscape choose that the sun shall be at noon and
look
towards the West or East and then draw. And if you turn towards
the North,
every object placed on that side will have no shadow,
particularly those
which are nearest to the [direction of the]
shadow of your head. And if you
turn towards the South every object
on that side will be wholly in shadow.
All the trees which are
towards the sun and have the atmosphere for their
background are
dark, and the other trees which lie against that darkness will
be
black [very dark] in the middle and lighter towards the edges.
The spaces between the parts in the mass of trees, and the spaces
between the
trees in the air, are, at great distances, invisible to
the eye; for, where
it is an effort [even] to see the whole it is
most difficult to discern the
parts.--But a confused mixture is the
result, partaking chiefly of the [hue]
which predominates. The
spaces between the leaves consist of particles of
illuminated air
which are very much smaller than the tree and are lost sight
of
sooner than the tree; but it does not therefore follow that they
are
not there. Hence, necessarily, a compounded [effect] is produced
of
the sky and of the shadows of the tree in shade, which both
together
strike the eye which sees them.
What outlines are seen in trees at a distance against the sky which
serves as
their background?
The outlines of the ramification of trees, where they
lie against
the illuminated sky, display a form which more nearly approaches
the
spherical on proportion as they are remote, and the nearer they
are
the less they appear in this spherical form; as in the first tree
_a_
which, being near to the eye, displays the true form of its
ramification; but
this shows less in _b_ and is altogether lost in
_c_, where not merely the
branches of the tree cannot be seen but
the whole tree is distinguished with
difficulty. Every object in
shadow, of whatever form it may be, at a great
distance appears to
be spherical. And this occurs because, if it is a square
body, at a
very short distance it loses its angles, and a little farther off
it
loses still more of its smaller sides which remain. And thus before
the
whole is lost [to sight] the parts are lost, being smaller than
the whole; as
a man, who in such a distant position loses his legs,
arms and head before
[the mass of] his body, then the outlines of
length are lost before those of
breadth, and where they have become
equal it would be a square if the angles
remained; but as they are
lost it is round.
All trees seen against the sun are dark towards the middle and this
shadow
will be of the shape of the tree when apart from others.
The shadows cast
by trees on which the sun shines are as dark as
those of the middle of the
tree.
The shadow cast by a tree is never less than the mass of the
tree
but becomes taller in proportion as the spot on which it
falls,
slopes towards the centre of the world.
The shadow will be
densest in the middle of the tree when the tree
has the fewest branches.
Every branch participates of the central shadow of every other
branch and
consequently [of that] of the whole tree.
The form of any shadow from a
branch or tree is circumscribed by the
light which falls from the side whence
the light comes; and this
illumination gives the shape of the shadow, and
this may be of the
distance of a mile from the side where the sun
is.
If it happens that a cloud should anywhere overshadow some part of
a
hill the [shadow of the] trees there will change less than in
the
plains; for these trees on the hills have their branches
thicker,
because they grow less high each year than in the plains.
Therefore
as these branches are dark by nature and being so full of shade,
the
shadow of the clouds cannot darken them any more; but the open
spaces
between the trees, which have no strong shadow change very
much in tone and
particularly those which vary from green; that is
ploughed lands or fallen
mountains or barren lands or rocks. Where
the trees are against the
atmosphere they appear all the same
colour--if indeed they are not very close
together or very thickly
covered with leaves like the fir and similar trees.
When you see the
trees from the side from which the sun lights them, you will
see
them almost all of the same tone, and the shadows in them will
be
hidden by the leaves in the light, which come between your eye
and
those shadows.
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.
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.
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.
OF TREES
AND LIGHTS ON THEM.
The best method of practice in representing country
scenes, or I
should say landscapes with their trees, is to choose them so
that
the sun is covered with clouds so that the landscape receives
an
universal light and not the direct light of the sun, which makes
the
shadows sharp and too strongly different from the lights.
All the leaves which hung towards the earth by the bending of the
shoots with
their branches, are turned up side down by the gusts of
wind, and here their
perspective is reversed; for, if the tree is
between you and the quarter of
the wind, the leaves which are
towards you remain in their natural aspect,
while those on the
opposite side which ought to have their points in a
contrary
direction have, by being turned over, their points turned
towards
you.
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 up in part, and
at the edges they show thinner.
But, when the
eye is between the cloud and the sun, the cloud has
the contrary effect to
the former, for the edges of its mass are
dark and it is light towards the
middle; and this happens because
you see the same side as faces the sun, and
because the edges have
some transparency and reveal to the eye that portion
which is hidden
beyond them, and which, as it does not catch the sunlight
like that
portion turned towards it, is necessarily somewhat darker. Again,
it
may be that you see the details of these rounded masses from the
lower
side, while the sun shines on the upper side and as they are
not so situated
as to reflect the light of the sun, as in the first
instance they remain
dark.
The black clouds which are often seen higher up than those which
are
illuminated by the sun are shaded by other clouds, lying between
them
and the sun.
Again, the rounded forms of the clouds that face the sun,
show their
edges dark because they lie against the light background; and to
see
that this is true, you may look at the top of any cloud that is
wholly
light because it lies against the blue of the atmosphere,
which is darker
than the cloud.
The colours in the middle of the rainbow mingle together.
The bow in
itself is not in the rain nor in the eye that sees it;
though it is generated
by the rain, the sun, and the eye. The
rainbow is always seen by the eye that
is between the rain and the
body of the sun; hence if the sun is in the East
and the rain is in
the West it will appear on the rain in the
West.
480.
When the air is condensed into rain it would produce a
vacuum if the
rest of the air did not prevent this by filling its place, as
it
does with a violent rush; and this is the wind which rises in
the
summer time, accompanied by heavy rain.
All the flowers which turn towards the sun perfect their seeds; but
not the
others; that is to say those which get only the reflection
of the sun.
We know for certain that sight is one of the most rapid actions we
can
perform. In an instant we see an infinite number of forms, still
we only take
in thoroughly one object at a time. Supposing that you,
Reader, were to
glance rapidly at the whole of this written page,
you would instantly
perceive that it was covered with various
letters; but you could not, in the
time, recognise what the letters
were, nor what they were meant to tell.
Hence you would need to see
them word by word, line by line to be able to
understand the
letters. Again, if you wish to go to the top of a building you
must
go up step by step; otherwise it will be impossible that you
should
reach the top. Thus I say to you, whom nature prompts to pursue
this
art, if you wish to have a sound knowledge of the forms of
objects
begin with the details of them, and do not go on to the
second
[step] till you have the first well fixed in memory and in
practice.
And if you do otherwise you will throw away your time, or
certainly
greatly prolong your studies. And remember to acquire
diligence
rather than rapidity.
I cannot forbear to mention among these precepts a new device for
study
which, although it may seem but trivial and almost ludicrous,
is nevertheless
extremely useful in arousing the mind to various
inventions. And this is,
when you look at a wall spotted with
stains, or with a mixture of stones, if
you have to devise some
scene, you may discover a resemblance to various
landscapes,
beautified with mountains, rivers, rocks, trees, plains,
wide
valleys and hills in varied arrangement; or again you may see
battles
and figures in action; or strange faces and costumes, and an
endless variety
of objects, which you could reduce to complete and
well drawn forms. And
these appear on such walls confusedly, like
the sound of bells in whose
jangle you may find any name or word you
choose to imagine.
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