together with the adaptations of animals in other directions, has received in recent years much merited attention, chiefly in behalf of development theories. But, whether these remarkable adaptations of animals to peculiar food and surroundings be the result of variation and development, or of special creation, they are equally wonderful.
IT is often said that the pleasure of form as contrasted with that of color is an intellectual pleasure arising from the perception of relations (unity in variety, proportion, etc.). In a sense this is true, for, as I hope to show in the course of this essay, the appreciation of form as compared with the enjoyment of color is saturated, so to speak, with the more refined sort of intellectual activity. But the fact that certain varieties of the arts of form, more especially outline drawing, dispense with the pleasure of color, and even with that of light and shade, suggests that the pleasure of visual form includes a sensuous element as well as an intellectual. It will be my special aim in this paper to bring out this somewhat neglected factor in visual gratification, and to indicate, so far as it is possible, its importance among the several factors, which together compose what we call beauty of form.
In pursuing this inquiry, it will be best to disregard the sensuous enjoyment of light and shade. For our present purpose, differences of light and shade are merely means of appreciating form. Again, it will be advisable to include all varieties of form as determined by the three dimensions of space. It is true that beauty of form, so far as it rests on purely visual feelings, is largely that of surface relations or of space in two dimensions. Yet it will be found to be practically impossible to treat of this apart from that other kind of beauty of form which embraces the charm of distance and perspective, and the characteristic attractiveness of solid shapes. As to the order of treatment, I shall set out with the elements of pleasure which are obviously direct—that is, arise from the activity of the visual organ—and trace the process of building up a more complex intellectual gratification on these. After that I shall pass to the indirect or associated elements of enjoyment. The simplest kind of visual appreciation of form is that of linear relations. For reasons to be spoken of presently, a straight line is the natural element of visible form, and the development of the visual perception of form (regarded as independent of that of the tactual) proceeds by a kind of synthesis of linear