The early pictures, in all ages, either merely indicate the character of bas-reliefs or single statues,—a cold continuity of outline, and an absence of foreshortening. The first move in advance, and that which constitutes their pictorial character, in contradistinction to sculpture, is an assemblage of figures, repeating the various forms contained in the principal ones, and thus rendering them less harsh by extension and doubling of the various shapes, as we often perceive in a first sketch of a work, where the eye of the spectator chooses, out of the multiplicity of outlines, those forms most agreeable to his taste. The next step to improvement, and giving the work a more natural appearance, is the influence of shadow, so as to make the outlines of the prominent more distinct, and those in the background less harsh and cutting, and consequently more retiring. The application of shadow, however, not only renders works of art more natural, by giving the appearance of advancing and retiring to objects represented upon a flat surface—thus keeping them in their several situations, according to the laws of aërial perspective—but enables the artist to draw attention to the principal points of the story, and likewise to preserve the whole in agreeable form, by losing and pronouncing individual parts. Coreggio was the first who carried out this principle to any great extent; but it was reserved for Rembrandt, by his boldness and genius, to put a limit to its further application. Breadth, the constituent character of this mode of treatment, cannot be extended; indeed, it is said that Rembrandt himself extended it too far; for, absorbing seven-eighths in obscurity and softness, though it renders the remaining portion more brilliant, yet costs too much. This principle, however, contains the greatest poetry of the art, in contradistinction to the severe outline and harsh colouring of the great historical style.