But we are aided still more by our habit of looking at things theoretically, apart from their immediate practical bearing. A savage can comprehend a carved image, but not so readily a picture. An Indian whom Catlin painted with half his face in shadow became the laughingstock of the tribe, as "the man with half a face." It is not necessary to suspect Mr. Catlin's chiaroscuro; what puzzled them was, doubtless, the bringing together in one view what they had seen only separate. They were accustomed to see the man in light and in shadow; but what they cared for, and therefore what they saw, was only the effect in making it more or less easy to recognize him and to ascertain his state of mind, intentions, etc. His face was either visible or obscured; if they could see enough for their purpose, they regarded only that. For it to be both at once was possible only from a point of view which they had not reached. A child takes the shading of the portrait for dirt,--that being the form in which darkening of the face is familiar to him. A carved image is easier comprehended, because it can be handled, turned about, and looked at on different sides, and a material connection thereby assured between the various aspects. To transfer this connection to the mind--to see varying distances in one vertical plane, so that mere gradations of light and shade shall suggest all these aspects arranged and harmonized in one view--is a farther step, and the difficulty increases with the variety embraced. Cicero was struck with this superiority in the artists of his time. "How much," he says, "do painters see in shadow and relief that we do not see!" Yet their perception seems strangely limited to us. The ancients had little notion of perspective. Their eyes were too sure and too well-practised to overlook the effect of position in foreshortening objects, and they were much experienced in the corrections required, and the effect of converging lines in increasing apparent distance was taken advantage of in their theatre-scenes. But they had not learned that the difference between the actual and the apparent form is thorough-going, so that the picture no longer stands in the attitude of passive indifference towards the beholder, but imposes upon him its own point of view. It was thought remarkable in the Minerva of Fabullus, that it had the appearance of always looking at the spectator, from whatever point it was viewed. This would be miraculous in a statue, and must seem so in the picture so long as it is looked upon only as one side of a statue. The wall-paintings of Pompeii, doubtless copies or reminiscences of Greek originals,--with masterly skill in the parts, and with some success in the landscape as far as it was easily reducible to one plane,--are only collections of fragments, and show utter incapacity to see the whole at once as a picture. For instance, in one of the many pictures of Narcissus beholding himself in the well, the head, which is