Chiaroscuro.—A few words about chiaroscuro will be useful. This is a term of great importance and frequent use with artists and writers up to within the last thirty or forty years. It has of late become almost unused. The reason for this was explained in the chapter on "Values." Nevertheless, it is well that the student should know what the word meant, and still means. Although he may hear and use it less frequently than if he had lived earlier in the century, the pictures, certain qualities of which no other word expresses, still exist, and are probably as immortal as anything in this world can be. He should know what those qualities are, and he should understand their relation to the work of to-day.

Chiaroscuro is described by an old writer as suggesting "a theme which is the most interesting, perhaps, in the whole range of the art of painting. Of vast importance, great extent, and extreme intricacy. Chiaroscuro is an Italian compound word whose two parts, chiar and oscuro, signify simply bright and obscure, or light and dark. Hence the art or branch of art that bears the name regards all the relations of light and shade, and this independently of coloring, notwithstanding that in painting, coloring and the clair-obscure are of their very nature inseparable. The art of clair-obscure, therefore, teaches the painter the disposition and arrangement in general of his lights and darks, with all their degrees, extreme and intermediate, of tint and shade, both in single objects, as the parts of a picture, and in combination as one whole, so as to produce the best representation possible in the best manner possible; that is, so as to produce the most desirable effect upon the senses and spirit of the observers. In a word, its end and aim are fidelity and beauty of imitation; its means, every effect of light; chromatic harmonies and contrasts; chromatic values, reflections; the degradations of atmospheric perspective, etc." The italics are mine.

You see at once that this covers a pretty wide field. But it is to be again noted that the use of chiaroscuro by the old painters meant not only the expression of the light and shade of nature, but the so arranging of the objects and the way that the light was permitted to fall on them, that certain parts of the picture became shadow, while the light was concentrated in some other part or parts. In this way the arrangement of the light and shade of a picture became a distinct element of composition, and a very important one. The quality of "light" was something to be emphasized by contrast. It is stated (whether truly or not) that the proportion of light to dark was according to a definite rule or principle with certain painters, some permitting more, and some less, space of canvas to be proportioned to light and to dark. The gradations of light and dark were studied of course; but the quantity of light spread over the canvas was calculated upon, so that the less space of light and the greater the space of dark, the more brilliant would be the main spot of light in the picture. They wrought with the quality of light and shade as an element, just as they would with the quality of line or of color, considered apart from objects or facts they might represent.

Arbitrary Lighting.—This is the arbitrary light and shade spoken of in the chapter on "Values"; and although the older painters included what we now call values in their word chiaroscuro, it is this fact of arbitrary lighting as opposed to accepting the light as it does fall, or selecting those places or times where it does naturally fall as we would like it to, that makes the difference between modern painting generally and the older method, and has made chiaroscuro as a word and as a quality of painting so much a thing of the past.

Light and Shade.—But we may use the old word with a more restricted meaning. If we use it to mean literally light and shade, the way light falls on objects and the relief due to the light side and the shadow side of them, we get a use which implies a very important and practical matter for present study.

Objects Visible by Light and Shadow.—If you will put a white egg on a piece of white paper, with another white paper back of it, you will see that it is only because the egg obstructs the light, the side of it towards the light preventing the light rays from touching the other side, and so casting a shadow on itself and on the paper, that the egg is visible. You will also see, if you manipulate the egg, that according as the light is concentrated or diffused, or according to the sharpness of the shadow and light, is the egg more or less distinct.

Contrast.—Apply these facts to other objects, and you will see how important the principle of contrast is to the representation of nature. Not only contrast of light and shade, but contrast of color. And you should make a study, both by setting up groups of objects in different lights, and by studying effects of lights wherever you are, of the possibilities and combinations of light and shadow.

Constant Observation.—The painter is constantly studying with his eyes. It is not necessary always to have the brush in your hand in order to be always studying. Keep your brain active in making observations and considering the relations in nature around you. The amount of material you can store up in this way is immense, to say nothing of the training it gives you in the use of your eyes, and in the practice of selection of motives for work. Schemes of color or composition are not usually deliberately invented within the painter's brain. They are in most cases the result of some suggestion from a chance effect noticed and remembered or jotted down, and afterwards worked out. Nature is the great suggester. It is the artist's business to catch the suggestion and make it his own. For nature seldom works out her own suggestions. The effect as nature gives it is either not complete, or is so evanescent as to be uncopyable. But the habit of constant receptivity on the part of the artist makes nature an infinite mine of possibilities to him.

Perception.—Only by continually observing and judging of contrasts and relations can the eye be trained to perceive subtle distinctions; yet it must be so trained, for all good work is dependent on these distinctions. Effects of Light.—It is important to study the different qualities of light. Take, for instance, the difference of character on a sunny day and on a gray day. On the former, fine distinctions of color are less pronounced; they are lost in the contrasts of sunlight and shadow. On a gray day the light is diffused; contrast is less, but the finer distinctions are more marked. For the study of the subtleties of color choose a gray day.

So, too, is the difference marked between the general light of out-doors and the more concentrated light of the house. The pitch is different. Outside, even in a dark day, the general character of light is clearer, more full, than in-doors.

There is nothing possible under the open sky like the strong contrasts you get from a single window in an otherwise unlighted room.

Compare, for instance, the character of the light and shade as shown in the illustrations on pages 156 and 159. The one is the diffused, out-of-door light, the other that from a studio window. The character of the subject has nothing to do with this quality. The head would have less of sharpness and contrast in the open air, and more reflected light.

Other differences to be studied as to quality of the light in the manner of its contrast, and also for its color quality, are to be seen in moonlight or nightlight as compared with daylight. Artificial light, such as lamp- and candle-light, gives marked effects also, which may be compared with daylight both as it is out-of-doors and in its more concentrated effects in the studio. Compare the picture of the "Woman Sewing by Lamplight," by Millet, with the "Canal" and the "Bohemian Woman" given above. The effects of gas and electric light also should be studied. Their characteristics both of contrast and, particularly, of color are worth your attention as a student, inasmuch as the essence of some pictures lies in these qualities.

Another matter of great importance to the student, and one which the same three illustrations just referred to may serve to show, is the effect on objects of the position of the point of entrance of the light with reference to them and to the observer. The simplest light is the side-light from a single window. This gives broad, sharp masses of light and shade, and makes the study of drawing and painting more simple. With the observer in the same relative position to the subject, as the light swings round towards a point back of him the contrasts become less, the relations more subtle and difficult of recognition, and naturally the study of them more difficult. In this position of light the values become "close." To make the object seen at all, it is necessary that the finest distinctions shall be observed.

Portrait painters have always been fond of a top light, which gives a direct concentrated light descending on the sitter, very similar in character to the side-light, but more favorable to the expression and drawing of the face.

Cross Lights.—The most confusing and difficult of study and representation are the "cross lights." If there are several windows or other points for the admission of light, and the sitter or object painted is between them, the light comes from all sides, so that the rays cross each other and there is no single scheme of light and shade. The rays from one side modify the shadows cast from the other side, and a perplexing and involved arrangement of values is the result. This is a favorite technical problem with painters, and its solution is splendid training; but the student who can successfully solve it is not far from the end of his "student days."