The hair affords an excellent instance of this agreeable complication. Soft curls agitated by the wind have been the theme of every poet. And yet, says Hogarth, "to show how excess ought to be avoided in intricacy, as well as in every other principle, the very same head of hair, wisped and matted together, would make the most disagreeable figure; because the eye would be perplexed, and at a fault, and unable to trace such a confused number of uncomposed and entangled lines." III. But animals have a higher system of organs and functions which peculiarly distinguishes them, and which presents new and peculiar characteristics of beauty. This consists of the organs by which they receive impressions from, and react upon the objects around them--the first organs which Nature presents having altogether external relations, and the first, consequently, in which we look for fitness for any purpose. The importance of fitness to the beauty of such objects is learned imperceptibly. Lines and forms, though the most elegant, fail to please us, if ill distributed in this respect: and objects, to a great extent destitute of the other characters of natural beauty, become beautiful when regarded in relation to fitness. Thus would this sense appear to be so powerful, as in some measure to regulate our other perceptions of beauty. It is fitness which leads us to admire in one animal, what would displease us if found in another. "The variety," says Barry, "and union of parts, which we call beautiful in a greyhound, are pleasing in consequence of the idea of agility which they convey. In other animals, less agility is united with more strength; and, indeed, all the different arrangements please because they indicate either different qualities, different degrees of qualities, or the different combinations of them." In relation to the various fitness of the human body, the same writer says: "We should not increase the beauty of the female bosom, by the addition of another protuberance; and the exquisite undulating transitions from the convex to the concave tendencies, could not be multiplied with any success. In fine, our rule for judging of the mode and degree of this combination of variety and unity, seems to be no other than that of its fitness and conformity to the designation of each species." But it is less necessary for me to adduce authorities in support of this truth, than to answer the objections that have been made to it by some of the ablest writers on the subject--objections which have generally their origin in the narrow views which these men have taken, and in those partial hypotheses which, even when true, led them to reject all other truth.