But the laws which Titian discovered have been unheeded for centuries; and they might have remained so, had not the mind of William Page felt the necessity of their revival and use.  To him there could be no chance-work.  Art must have laws as definite and immutable as those of science; indeed, the body in which the spirit of art is developed, and through which it acts, must be science itself.  He saw, that, if exact imitation of Nature be taken as the law in painting, there must inevitably occur the difficulty to which we have before referred,—­that, above a certain point, paint no longer undergoes transfiguration, thereby losing its character as mere coloring material,—­that, if the ordinary tone of Nature be held as the legitimate key-note, the scope of the palette would be exhausted before success could be achieved.

Any one of Turner’s latest pictures may serve to illustrate the nature of this difficulty.  Although in his early practice he was remarkable for his judicious restraint, it is evident that the splendors of the higher phenomena of light had for him unlimited fascination; and he may be traced advancing cautiously through that period of his career which was marked by the influence of Claude, toward what he hoped would prove, and perhaps believed to be, a realization of such splendors.

It must have been observed by those who have studied his later pictures, that, while the low passages of the composition are wonderfully fine and representative, all the higher parts, those supposed or intended to stand for the radiance of dazzling light, fail utterly in representative capacity.  There is an abundance of the most brilliant pigment, but it is still paint,—­unmitigated ochre and white lead.  The spectator is obliged to recede from the picture until distance enables the eye to transmute the offending material and reconcile the conflicting passages.

To accomplish the result of rendering the quality and effect of high light was one of the problems to which Mr. Page years ago turned his attention; and he found its solution in the transposition of the scale.  The pitch of Nature could not be adopted as the immutable in art.  That were impossible, unless art presumed to cope with Nature.

More than he, no man could respect the properties and qualities of the visible world.  His ideas of the truthful rendering of that which became the subject of his pencil might seem preposterous to those who knew not the wonderful significancy which he attached to individual forms and tints.  Yet, in imitation, where is the limit?  What is possible?  Must there be any sacrifice?

Evidently there must be; and of course it follows that the less important must be sacrificed.  Nature herself has taught the artist that the most variable of all her phenomena is that of tone.  Other truths of Nature have a character of permanency which the artist cannot modify without violating the first principles of art.  He is required to render the essential; and to render the essential of that which art cannot sacrifice, if it would, and continue art, he foregoes the non-essential and evanescent.