green grass in bright sunshine shows that Leonardo clearly apprehended the _plein-airiste’s_ problem. Doubtless it will prove possible to show that he foresaw still later methods. He rejected these methods because it seemed to him that the artist could work most freely by moving midway between light and darkness, and, indeed, he, first of painters, succeeded in combining them—just as he said also that Pleasure and Pain should be imaged as twins since they are ever together, yet back to back because ever contrary—and devised the method of _chiaroscuro_, by which light reveals the richness of shade and shade heightens the brightness of light. No invention could be more characteristic of this man whose grasp of the world ever involved the union of opposites, and the opposites both apprehended more intensely than falls to the lot of other men. Yet it is noteworthy that Leonardo constantly speaks of the artist’s function as searching into and imitating Nature, a view which the orthodox artist anathematises. But Leonardo was not the orthodox artist, not even, perhaps, as he is traditionally regarded, one of the world’s supreme painters. For one may sympathise with Mr. Berenson’s engaging attempt—unconvincing as it has seemed—to “expose” Leonardo. The drawings Mr. Berenson, like every one else, admires whole-heartedly, but, save for the unfinished “Adoration,” which he regards as a summit of art, he finds the paintings mostly meaningless and repellent. He cannot rank Leonardo as an artist higher than Botticelli, and concludes that he was not so much a great painter as a great inventor in painting. With that conclusion it is possible that Leonardo himself would have agreed. Painting was to him, he said, a subtle invention whereby philosophical speculation can be applied to all the qualities of forms. He seemed to himself to be, here and always, a man standing at the mouth of the gloomy cavern of Nature with arched back, one hand resting on his knee and the other shading his eyes, as he peers intently into the darkness, possessed by fear and desire, fear of the threatening gloom of that cavern, desire to discover what miracle it might hold. We are far here from the traditional attitude of the painter; we are nearer to the attitude of that great seeker into the mysteries of Nature, one of the very few born of women to whom we can ever even passingly compare Leonardo, who felt in old age that he had only been a child gathering shells and pebbles on the shore of the great ocean of truth.