If we require a large space for repose, by getting the light at one or other side of the picture, the light should of necessity possess some striking quality, to compensate so great a sacrifice of space; while a multitude of less important objects may find a mysterious locality in the reposing mass. ([Plate 2, figs. 1], [2].)
In some of Rembrandt's etchings, a very small but brilliant point of light is carried through the composition, by the softest gradations, into the intense depth of shadow, by striking the tops only of the figures, parts of architecture, &c., until completely lost. The principal light must never be placed in the centre, but either on one side or other.
A single mass of light will have the greatest force when brought in immediate contact with a dark background: so will a dark object tell with equal power when opposed to the strongest light. So a figure, clothed in black and white, and placed on one side of the foreground, will focus all the other lights and shadows, which will immediately keep their places in the picture—so they be less in strength. In proportion to the number of forms in the composition, this rule may be equally applied to a group, if it agree in its outline, and does not disturb the masses on which it depends for repose.
If the picture be generally light, or the greater part in half tint, a single object or point of dark will be often found sufficient to key the whole,—placed at the opposing angle on the side opposite the darkest part.
The outline of an object we would bring most forward should come out cutting and strong from its surrounding shadow, while the other masses will retire in proportion to the absence of the opposition of density employed in preventing their approach. It may not be impossible that these few words convey the impression of what we mostly intend.
The small and immaterial lights, catching the edges of objects carried into the shadow, are of the greatest usefulness in giving depth and intensity to it, while they assist the work by carrying the communicating medium through it.
Carrying the shadow across the middle of the subject is attended with many advantages; among which are, bringing the foreground into extreme vigour; furnishing ourselves with greater facilities in getting away the background; and more readily obtaining distance and repose by blending the horizon with the clouds; while the figures are brought up in cutting relief against it. ([Plate 3.])
A mass of landscape in middle tint—such as a broken common, fields, clumps of foliage, &c.—sweeping across the picture at a third, or little more, its height from the bottom, with a bold tree or group printing its dark form on the lightest part of the sky, and lifting itself from a bright sunny bank laid on the bottom edge of the design, carried on by a dark object or two, with cutting lights and intense shadows in the weeds, stones, &c., of the foreground to support it, the clouds graduating upwards from the horizon and mingling with the middle space at the opposite side of the principal group, seems to have been a favourite arrangement with Gaspar Poussan, Cuyp, and many of the Dutch, as at present it is with Turner, and many of the modern,—offering great advantages from the numerous scenes in nature for ever opening to our view through the broad masses of shadow, flung from the passing clouds across the country, and possessing every variety of tint, sobered and covered down by the extent and transparency of the shadows, while the brilliant lights come out with all the vigorous warmth the sun invests them with.
A walk into the fields, or across a heath, can scarcely be taken, when the clouds are floating along, without an effect corresponding with this being seen. A part of the principal group will sometimes be in light while the rest is in deep shadow, or may appear so from the different colours of the trees; in which case, it will blend more gently with the sky, and more intensely focus the depth of shadow, if the lighter colour be interposed between it and the sky, losing a little of its force, but gaining harmony and union, together with the advantage of carrying the warm colour of the foreground up into the foliage, and extending it more gradually through the clouds.
Three lights, differing in strength—the centre one the strongest—and placed at different angles, has universally been found an agreeable arrangement. This mode may be always pursued with a certain degree of success. The etchings and drawings after this manner are very numerous,—perhaps from its easy management.