Turner and Claude often brought the highest light and deepest dark together in close opposition through a series of big gradations of objects, the most light-giving device known in painting. The introduction of a shadow through the foreground or middle distance, over which the vision travels to the light beyond, always gives great depth; another of the devices in landscape painting frequently met with in the work of Claude, Ruysdael, Corot, Vandevelde, Cuyp, Inness, Wyant, Ranger, and all painters of landscape who attain light by the use of a graded scale of contrasts. A cumulative gradation which suddenly stops has the same force in light and shade as a long line which suddenly changes into a short line of opposed direction. They are both equivalent to a pause in music, awakening an attention at such a point, and only to be employed where there is something important to follow.
It is the experience of all picture makers that under the limitations which special subjects impose they are often obliged to search for an equivalent with which to comply with the requirements of composition.
If, for instance, in the arrangement of a picture it is found necessary to move an object—a tree, figure or other item of importance, instead of obliteration and repainting, the result is attained by creating an attraction on the side from which it is to be moved.
By so doing the range of the picture is increased and its space seems to take in more than its limits presupposed: If an isolated tree standing against a mass of trees, by opening the sky through that mass or by creating attraction of color or form therein, the vision is led to the far side of the object to be moved, which is thereby crowded out of its position in the balancing scheme.
An object upon a surface may frequently give place to a dark or light variation of the surface itself which becomes an equivalent of attraction.
Several objects may be made to balance without rearrangement though the marginal proportions of the picture are altered. The _ship and moon_ compose as an upright, but not in long shape without either the following line which indicates the ship’s course; or an object of attraction in the opposing half either in the distance or foreground, much less being required in the latter than the former. The equivalent therefore of the leading line is the object on the farther shore.
