133. Finally, the qualities and relations of natural colours, the means of imitating them, and the laws by which they become separately beautiful, and in association harmonious, are the subjects of the third and final division of the painter's study. I shall endeavour at once to state to you what is most immediately desirable for you to know on each of these topics, in this and the two following lectures.
134. What we have to do, then, from beginning to end, is, I repeat once more, simply to draw spaces of their true shape, and to fill them with colours which shall match their colours; quite a simple thing in the definition of it, not quite so easy in the doing of it.
But it is something to get this simple definition; and I wish you to notice that the terms of it are complete, though I do not introduce the term "light," or "shadow." Painters who have no eye for colour have greatly confused and falsified the practice of art by the theory that shadow is an absence of colour. Shadow is, on the contrary, necessary to the full presence of colour; for every colour is a diminished quantity or energy of light; and, practically, it follows from what I have just told you—(that every light in painting is a shadow to higher lights, and every shadow a light to lower shadows)—that also every colour in painting must be a shadow to some brighter colour, and a light to some darker one—all the while being a positive colour itself. And the great splendour of the Venetian school arises from their having seen and held from the beginning this great fact—that shadow is as much colour as light, often much more. In Titian's fullest red the lights are pale rose-colour, passing into white—the shadows warm deep crimson. In Veronese's most splendid orange, the lights are pale, the shadows crocus colour; and so on. In nature, dark sides if seen by reflected lights, are almost always fuller or warmer in colour than the lights; and the practice of the Bolognese and Roman schools, in drawing their shadows always dark and cold, is false from the beginning, and renders perfect painting for ever impossible in those schools, and to all who follow them.
135. Every visible space, then, be it dark or light, is a space of colour of some kind, or of black or white. And you have to enclose it with a true outline, and to paint it with its true colour.
But before considering how we are to draw this enclosing line, I must state to you something about the use of lines in general, by different schools.
I said just now that there was no difference between the masses of colour of which all visible nature is composed, except in texture. Now textures are principally of three kinds:—
(1) Lustrous, as of water and glass.
(2) Bloomy, or velvety, as of a rose-leaf or peach.
(3) Linear, produced by filaments or threads, as in feathers, fur, hair, and woven or reticulated tissues.
All these three sources of pleasure to the eye in texture are united in the best ornamental work. A fine picture by Fra Angelico, or a fine illuminated page of missal, has large spaces of gold, partly burnished and lustrous, partly dead;—some of it chased and enriched with linear texture, and mingled with imposed or inlaid colours, soft in bloom like that of the rose-leaf. But many schools of art affect for the most part one kind of texture only, and a vast quantity of the art of all ages depends for great part of its power on texture produced by multitudinous lines. Thus, wood engraving, line engraving properly so called, and countless varieties of sculpture, metal work, and textile fabric, depend for great part of the effect, for the mystery, softness, and clearness of their colours, or shades, on modification of the surfaces by lines or threads. Even in advanced oil painting, the work often depends for some part of its effect on the texture of the canvas.
136. Again, the arts of etching and mezzotint engraving depend principally for their effect on the velvety, or bloomy texture of their darkness, and the best of all painting is the fresco work of great colourists, in which the colours are what is usually called dead; but they are anything but dead, they glow with the luminous bloom of life. The frescoes of Correggio, when not repainted, are supreme in this quality.
137. While, however, in all periods of art these different textures are thus used in various styles, and for various purposes, you will find that there is a broad historical division of schools, which will materially assist you in understanding them. The earliest art in most countries is linear, consisting of interwoven, or richly spiral and otherwise involved arrangements of sculptured or painted lines, on stone, wood, metal or clay. It is generally characteristic of savage life, and of feverish energy of imagination. I shall examine these schools with you hereafter, under the general head of the "Schools of Line."[12]