In this place I had proposed to draw on my La Plata notebooks for some amusing illustrations of this fact of our two sights; but it is not necessary to go so far afield for illustrations, or to insist on a thing so familiar. "The shepherd knows his sheep," is a saying just as true of this country--of Scotland, at all events--as of the far East. Detectives, also military men who take an interest in their profession, see faces more sharply than most people, and remember them as distinctly as others remember the faces of a very limited number of individuals--of those they love or fear or constantly associate with. Sailors see atmospheric changes which are not apparent to others; and, in like manner, the physician detects the signs of malady in faces which to the uninstructed vision seem healthy enough. And so on through the whole range of professions and pursuits which men have: each person inhabits a little world of his own, as it were, which to others is only part of the distant general blueness obscuring all things, but in which, to him, every object stands out with wonderful clearness, and plainly tells its story. All this may sound very trite, very trivial and matter of common knowledge--so common as to be known to every schoolboy and to the boy that goeth not to school; yet it is because this simple familiar fact has been ignored, or has not always been borne in mind by our masters, that they have taught us an error, namely, that savages are our superiors in visual power, and that the difference is so great that ours is a dim decaying sense compared with their brilliant faculty, and that only when we survey the prospect through powerful field-glasses do we rise to their level and see the world as they see it. The truth is that the savage sight is no better than ours, although it might seem natural enough to think the contrary, on account of their simple natural life in the desert, which is always green and restful to the eye, or supposed to be so; and because they have no gas nor even candlelight to irritate the visual nerve, and do themselves no injury by poring over miserable books.