He painted everything in Barbizon--the plains and the hills, the river and the forest, all the seasons of the year and all the hours of the day. The succession of his moods is as inexhaustible as boundless nature herself. Skies gilded by the setting sun, phases of dewy morning, plains basking in light, woods in the russet-yellow foliage of autumn: these are the subjects of Théodore Rousseau--an endless procession of poetic effects, expressed at first by the mere instinct of emotion and later with a mathematical precision which is often a little strained, though always irresistibly forcible. Marvellous are his autumn landscapes with their ruddy foliage of beech; majestic are those pictures in which he expressed the profound sentiment of solitude as it passes over you in the inviolate tangle of the forest, inviting the spirit to commune with itself; but especially characteristic of Rousseau are those plains with huge isolated trees, over which the mere light of common day rests almost coldly and dispassionately. [Illustration: COROT AT WORK.] It is an artistic or psychological anomaly that in this romantic generation a man could be born in whom there was nothing of the Romanticist. Théodore Rousseau was an experimentalist, a great worker, a restless and seeking spirit, ever tormented and unsatisfied with itself, a nature wholly without sentimentality and impassionless, the very opposite of his predecessor Huet. Huet made nature the mirror of the passions, the melancholy and the tragic suffering which agitate the human spirit with their rage. Whilst he celebrated the irresistible powers and blind forces, the elemental genii which rule the skies and the waters, he wanted to waken an impression of terror and desolation in the spirit of the beholder. He piled together masses of rock, lent dramatic passion to the clouds, and revelled with delight in the sharpest contrasts. Rousseau's pervasive characteristic is absolute plainness and actuality. Such a simplicity of shadow had never existed before. Since the Renaissance artists had systematically heightened the intensity of shadows for the sake of effect; Rousseau relied on the true and simple doctrine that may be formulated in the phrase: the more light there is the fainter and more transparent are the shadows, not the darker, as Decamps and Huet painted them. Or, to speak more generally, in nature the intensity of shadows stands in an inverse relation to the intensity of the light. [Illustration: COROT. DAPHNIS AND CHLOE.]