But it is not the mere predominance of the senses, or the strength and acuteness of the sense which so broadly and radically separates whites and negroes. They are entirely different in the manifestations of these qualities. As has been observed, there are few if any near-sighted negroes, or negroes with other defects of vision, and the sense of smell in negroes permits them to discriminate and to indicate the presence of the rattle snake, or other venomous serpents. And in respect to the sense of touch or feeling, the peculiarity of the negro nature is perhaps most remarkable of all. This sense in the white person, though universal of course, is mainly located in the hand and fingers. Sir Charles Bell, an eminent English surgeon, has written an interesting work—one of the Bridgewater treatises—on the flexibility and adaptation of the human hand, and other volumes might be given to the world without exhausting the subject. The universal law of adaptation, indeed, demands that the sense of touch, the flexibility of the hand, the delicacy of the fingers, should be in accord with the large brain and commanding intellect, otherwise the world itself would long since have come to a stand-still, and human invention ended with the antediluvians. It is true the structure—the arrangement of the bones, muscles, tendons, etc., in short, the mere mechanism of the hand, is essential, but without the sense of feeling, or that delicacy of touch found only in the fingers of the Caucasian, the mechanical perfections of the hand would be comparatively useless.