The first conception of a picture is always embodied in the form of a sketch, and the artist will make as many sketches as he thinks of changes in his original idea. It is in this form that he works out his picture problem. He is troubled here by nothing but the one thing he has in mind at this time. It may be an arrangement of line or of mass. He changes and rearranges it as he pleases, not troubling himself in the least with exactness of drawing, of modelling, of color, nor of anything but that one of composition. It may be a scheme of color, and here again the spots of pigment only vaguely resemble the things they will later represent; now they are only composition of color to the painter, and everything bends to that. When this has been decided on, has been successfully worked out, then it is time enough to think of other things. And think of other things he does, before he makes his picture; but not in this sketch; in another sketch or other sketches, each with its own problem, or in studies which will furnish more material to be used later; or in the picture itself, where the problem is the unity of the various ideas within the great whole in the completed painting.
It is the sketch on which the picture rests for its singleness of purpose. No picture but begins in this way, whether it is afterwards built up on the same canvas or not. The sketch points the way. But all the preliminary sketches of a painting are not problems of composition or color; are not conceptions of the brain. There are suggestions received from nature which the painter perceives rather than conceives. Possibilities show themselves in these, but it is in the sketch that they first become tangible and stable. This is the sketch from nature, always the record of an impression, the note of an idea hinted by one fact or condition seen more sharply or clearly than any or all of the thousands which surrounded it at the moment.
The painter must always sketch from nature. Only by so doing can he be constantly in touch with her, and receive her suggestions unaffected by multitudinous facts. The sketch preserves for him the evanescent effects of nature, which the study would not so entirely, because not so simply, grasp. The sudden storm approaches; the fleeting cloud shadow; or the last gleam of afterglow; these, as well as the more permanent, but equally charming effects of mass against mass of wood and sky, or of meadow and hill, he can only store up for future use or reference in his sketches.
Main Idea Only.—In the making of the sketch, then, no problem should come in but that of the expression of the main idea,—no problem of drawing or of manipulation of color. To get the idea expressed in the most direct and immediate and convenient way, anything will do to sketch on or with; that which presents the least difficulty is the best. The matter of temperament, of course, comes in largely, and technical facility. That which you can use most freely, use in your sketching, and keep for other occasions the new means or medium. Use freely, if you can, black and white for whatever black and white will express, and pigment for all color effects. Oil for greatest certainty and facility of correction.
Quick Work.—Make your sketch at one sitting, or you will have something which is not a sketch. Work long enough, and it may be a study; but more than one sitting makes it neither one thing nor the other. To say nothing of the fact that the conditions are unlikely to be exactly the same again, you are almost sure on the second working to have lost the first impression,—the freshness and directness of purpose which the first impress gives; and this is the very heart of a sketch. You must never lose sight of what was the original purpose of it; never forget what it was which first made you want to paint it. No matter what else you get or do not get, if you lose this you lose all that can give it life or reality.
The very fact that you have limited yourself to one working makes you concentrate on that which first caught your attention, and that is what you want to seize.
Overworkings and after-paintings will only interfere with the directness and force with which this is expressed.
Remember that nature is never at rest. You must catch her on the wing, and the more quickly you do it the more vivid will be the effect.