And that the serpentine line, by its waving and winding at the same time different ways, leads the eye in a pleasing manner along the continuity of its variety, if I may be allowed the expression; and which by its twisting so many different ways, may be said to inclose (tho' but a single line) varied contents; and therefore all its variety cannot be express'd on paper by one continued line, without the assistance of the imagination, or the help of a figure; see [Fig. 26 T p. I] where that sort of proportion'd, winding line, which will hereafter be call'd the precise serpentine line, or line of grace, is represented by a fine wire, properly twisted round the elegant and varied figure of a cone.
[CHAPTER VIII.]
Of what sort of Parts, and how pleasing Forms are composed.
Thus far having endeavoured to open as large an idea as possible of the power of variety, by having partly shewn that those lines which have most variety in themselves, contribute most towards the production of beauty; we will next shew how lines may be put together, so as to make pleasing figures or compositions.
In order to be as clear as possible, we will give a few examples of the most familiar and easy sort, and let them serve as a clue to be pursued in the imagination: I say in the imagination chiefly, for the following method is not meant always to be put in practice, or follow'd in every case, for indeed that could hardly be, and in some it would be ridiculously losing time if it could——Yet there may be cases where it may be necessary to follow this method minutely; as for example, in architecture.
I am thoroughly convinc'd in myself, however it may startle some, that a completely new and harmonious order of architecture in all its parts, might be produced by the following method of composing, but hardly with certainty without it; and this I am the more apt to believe, as upon the strictest examination, those four orders of the ancients, which are so well established for beauty and true proportion, perfectly agree with the scheme we shall now lay down.
This way of composing pleasing forms, is to be accomplished by making choice of variety of lines, as to their shapes and dimensions; and then again by varying their situations with each other, by all the different ways that can be conceived: and at the same time (if a solid figure be the subject of the composition) the contents or space that is to be inclosed within those lines, must be duly consider'd and vary'd too, as much as possible, with propriety. In a word, it may be said, the art of composing well is the art of varying well. It is not expected that this should at first be perfectly comprehended, yet I believe it will be made sufficiently clear by the help of the examples following.
The figure [Fig. 29 T p. I], represents the simple and pleasing figure of a bell; this shell, as we may call it, is composed of waving lines, encompassing, or bounding within it, the varied space marked with dotted lines: here you see the variety of the space within is equal to the beauty of its form without, and if the space, or contents, were to be more varied, the outward form would have still more beauty.