The Notebooks of Leonardo Da Vinci

Page 297

Take care that the perspective of colour does not disagree with the
size of your objects, hat is to say: that the colours diminish from
their natural [vividness] in proportion as the objects at various
distances dimmish from their natural size.

On the relative density of the atmosphere (298--290).

Page 296

The medium lying between the eye and the object seen, tinges that
object with its colour, as the blueness of the atmosphere makes the
distant mountains appear blue and red glass makes objects seen
beyond it, look red. The light shed round them by the stars is
obscured by the darkness of the night which lies between the eye and
the radiant light of the stars.

Page 295

OF AERIAL PERSPECTIVE.

There is another kind of perspective which I call Aerial
Perspective, because by the atmosphere we are able to distinguish
the variations in distance of different buildings, which appear
placed on a single line; as, for instance, when we see several
buildings beyond a wall, all of which, as they appear above the top
of the wall, look of the same size, while you wish to represent them
in a picture as more remote one than another and to give the effect
of a somewhat dense atmosphere. You know that in an atmosphere of
equal density the remotest objects seen through it, as mountains, in
consequence of the great quantity of atmosphere between your eye and
them--appear blue and almost of the same hue as the atmosphere
itself [Footnote 10: _quado il sole e per leuante_ (when the sun is
in the East). Apparently the author refers here to morning light in
general. H. LUDWIG however translates this passage from the Vatican
copy "_wenn namlich die Sonne (dahinter) im Osten steht_".] when the
sun is in the East [Footnote 11: See Footnote 10]. Hence you must
make the nearest building above the wall of its real colour, but the
more distant ones make less defined and bluer. Those you wish should
look farthest away you must make proportionately bluer; thus, if one
is to be five times as distant, make it five times bluer. And by
this rule the buildings which above a [given] line appear of the
same size, will plainly be distinguished as to which are the more
remote and which larger than the others.

Page 294

HOW A PAINTER SHOULD CARRY OUT THE PERSPECTIVE OF COLOUR IN
PRACTICE.

In order to put into practice this perspective of the variation and
loss or diminution of the essential character of colours, observe at
every hundred braccia some objects standing in the landscape, such
as trees, houses, men and particular places. Then in front of the
first tree have a very steady plate of glass and keep your eye very
steady, and then, on this plate of glass, draw a tree, tracing it
over the form of that tree. Then move it on one side so far as that
the real tree is close by the side of the tree you have drawn; then
colour your drawing in such a way as that in colour and form the two
may be alike, and that both, if you close one eye, seem to be
painted on the glass and at the same distance. Then, by the same
method, represent a second tree, and a third, with a distance of a
hundred braccia between each. And these will serve as a standard and
guide whenever you work on your own pictures, wherever they may
apply, and will enable you to give due distance in those works. [14]
But I have found that as a rule the second is 4/5 of the first when
it is 20 braccia beyond it.

[Footnote: This chapter is one of those copied in the Manuscript of
the Vatican library Urbinas 1270, and the original text is rendered
here with no other alterations, but in the orthography. H. LUDWIG,
in his edition of this copy translates lines 14 and 15 thus: "_Ich
finde aber als Regel, dass der zweite um vier Funftel des ersten
abnimmt, wenn er namlich zwanzig Ellen vom ersten entfernt ist
(?)"_. He adds in his commentary: "_Das Ende der Nummer ist wohl
jedenfalls verstummelt_". However the translation given above shows
that it admits of a different rendering.]

The rules of aerial perspective (295--297).

Page 293

ALL COLOURS ARE AT A DISTANCE UNDISTINGUISHABLE AND UNDISCERNIBLE.

All colours at a distance are undistinguishable in shadow, because
an object which is not in the highest light is incapable of
transmitting its image to the eye through an atmosphere more
luminous than itself; since the lesser brightness must be absorbed
by the greater. For instance: We, in a house, can see that all the
colours on the surface of the walls are clearly and instantly
visible when the windows of the house are open; but if we were to go
out of the house and look in at the windows from a little distance
to see the paintings on those walls, instead of the paintings we
should see an uniform deep and colourless shadow.

The practice of the prospettiva de colori.

Page 292

Of the edges [outlines] of shadows. Some have misty and ill defined
edges, others distinct ones.

No opaque body can be devoid of light and shade, except it is in a
mist, on ground covered with snow, or when snow is falling on the
open country which has no light on it and is surrounded with
darkness.

And this occurs [only] in spherical bodies, because in other bodies
which have limbs and parts, those sides of limbs which face each
other reflect on each other the accidental [hue and tone] of their
surface.

An experiment.

Page 291

OF THE VISIBILITY OF COLOURS.

Which colour strikes most? An object at a distance is most
conspicuous, when it is lightest, and the darkest is least visible.

An exceptional case.

Page 290

As to the colours of objects: at long distances no difference is
perceptible in the parts in shadow.

Page 289

The variety of colour in objects cannot be discerned at a great
distance, excepting in those parts which are directly lighted up by
the solar rays.

Page 288

WHETHER THE COLOURS OF THE RAINBOW ARE PRODUCED BY THE SUN.

The colours of the rainbow are not produced by the sun, for they
occur in many ways without the sunshine; as may be seen by holding a
glass of water up to the eye; when, in the glass--where there are
those minute bubbles always seen in coarse glass--each bubble, even
though the sun does not fall on it, will produce on one side all the
colours of the rainbow; as you may see by placing the glass between
the day light and your eye in such a way as that it is close to the
eye, while on one side the glass admits the [diffused] light of the
atmosphere, and on the other side the shadow of the wall on one side
of the window; either left or right, it matters not which. Then, by
turning the glass round you will see these colours all round the
bubbles in the glass &c. And the rest shall be said in its place.

THAT THE EYE HAS NO PART IN PRODUCING THE COLOURS OF THE RAINBOW.

In the experiment just described, the eye would seem to have some
share in the colours of the rainbow, since these bubbles in the
glass do not display the colours except through the medium of the
eye. But, if you place the glass full of water on the window sill,
in such a position as that the outer side is exposed to the sun's
rays, you will see the same colours produced in the spot of light
thrown through the glass and upon the floor, in a dark place, below
the window; and as the eye is not here concerned in it, we may
evidently, and with certainty pronounce that the eye has no share in
producing them.

OF THE COLOURS IN THE FEATHERS OF CERTAIN BIRDS.

There are many birds in various regions of the world on whose
feathers we see the most splendid colours produced as they move, as
we see in our own country in the feathers of peacocks or on the
necks of ducks or pigeons, &c.

Again, on the surface of antique glass found underground and on the
roots of turnips kept for some time at the bottom of wells or other
stagnant waters [we see] that each root displays colours similar to
those of the real rainbow. They may also be seen when oil has been
placed on the top of water and in the solar rays reflected from the
surface of a diamond or beryl; again, through the angular facet of a
beryl every dark object against a background of the atmosphere or
any thing else equally pale-coloured is surrounded by these rainbow
colours between the atmosphere and the dark body; and in many other
circumstances which I will not mention, as these suffice for my
purpose.

_VI._

_'Prospettiva de' colri' (Perspective of Colour)_

_and_

_'Prospettiva aerea' (Aerial Perspective)._

_Leonardo distinctly separates these branches of his subject, as may
be seen in the beginning of No._ 295. _Attempts have been made to
cast doubts on the results which Leonardo arrived at by experiment
on the perspective of colour, but not with justice, as may be seen
from the original text of section_ 294.

_The question as to the composition of the atmosphere, which is
inseparable from a discussion on Aerial Perspective, forms a
separate theory which is treated at considerable length. Indeed the
author enters into it so fully that we cannot escape the conviction
that he must have dwelt with particular pleasure on this part of his
subject, and that he attached great importance to giving it a
character of general applicability._

General rules (289--291).

Page 287

Treat of the rainbow in the last book on Painting, but first write
the book on colours produced by the mixture of other colours, so as
to be able to prove by those painters' colours how the colours of
the rainbow are produced.

Page 286

OF PAINTING.

Colours seen in shadow will display more or less of their natural
brilliancy in proportion as they are in fainter or deeper shadow.

But if these same colours are situated in a well-lighted place, they
will appear brighter in proportion as the light is more brilliant.

THE ADVERSARY.

The variety of colours in shadow must be as great as that of the
colours in the objects in that shadow.

THE ANSWER.

Colours seen in shadow will display less variety in proportion as
the shadows in which they lie are deeper. And evidence of this is to
be had by looking from an open space into the doorways of dark and
shadowy churches, where the pictures which are painted in various
colours all look of uniform darkness.

Hence at a considerable distance all the shadows of different
colours will appear of the same darkness.

It is the light side of an object in light and shade which shows the
true colour.

On the colours of the rainbow (287. 288).

Page 285

An object represented in white and black will display stronger
relief than in any other way; hence I would remind you O Painter! to
dress your figures in the lightest colours you can, since, if you
put them in dark colours, they will be in too slight relief and
inconspicuous from a distance. And the reason is that the shadows of
all objects are dark. And if you make a dress dark there is little
variety in the lights and shadows, while in light colours there are
many grades.

Page 284

WHY BEAUTIFUL COLOURS MUST BE IN THE [HIGHEST] LIGHT.

Since we see that the quality of colour is known [only] by means of
light, it is to be supposed that where there is most light the true
character of a colour in light will be best seen; and where there is
most shadow the colour will be affected by the tone of that. Hence,
O Painter! remember to show the true quality of colours in bright
lights.

Page 283

WHAT PORTION OF A COLOURED SURFACE OUGHT IN REASON TO BE THE MOST
INTENSE.

If _a_ is the light, and _b_ illuminated by it in a direct line,
_c_, on which the light cannot fall, is lighted only by reflection
from _b_ which, let us say, is red. Hence the light reflected from
it, will be affected by the hue of the surface causing it and will
tinge the surface _c_ with red. And if _c_ is also red you will see
it much more intense than _b_; and if it were yellow you would see
there a colour between yellow and red.

On the use of dark and light colours in painting (284--286).

Page 282

PERSPECTIVE.

That side of an object in light and shade which is towards the light
transmits the images of its details more distinctly and immediately
to the eye than the side which is in shadow.

PERSPECTIVE.

The solar rays reflected on a square mirror will be thrown back to
distant objects in a circular form.

PERSPECTIVE.

Any white and opaque surface will be partially coloured by
reflections from surrounding objects.

[Footnote 281. 282: The title line of these chapters is in the
original simply _"pro"_, which may be an abbreviation for either
_Propositione_ or _Prospettiva_--taking Prospettiva of course in its
widest sense, as we often find it used in Leonardo's writings. The
title _"pro"_ has here been understood to mean _Prospettiva_, in
accordance with the suggestion afforded by page 10b of this same
MS., where the first section is headed _Prospettiva_ in full (see
No. 94), while the four following sections are headed merely _"pro"_
(see No. 85).]