I should not have given my reader the trouble of compleating, by the help of his imagination, the foregoing figure, but as it may contribute to the more ready and particular conception of that intricate variety which twisted figures give to this species of shade, and to facilitate his understanding the cause of its beauty, wherever it may be seen on surfaces of ornament, when it will be found no where more conspicuous than in a fine face, as will be seen upon further enquiry.
The dotted line [Fig. 97 B p. I], which begins from the concave part, under the arch of the brow, near the nose, and from thence winding down by the corner of the eye, and there turning obliquely with the round of the cheek, shews the course of that twist of shades in a face, which was before described by the horn; and which may be most perfectly seen in the life, or in a marble busto, together with the following additional circumstances still remaining to be described.
As a face is for the most part round, it is therefore apt to receive reflected light on its shadowy side[15], which not only adds more beauty by another pleasing tender gradation, but also serves to distinguish the roundness of the cheeks, &c. from such parts as sink and fall in: because concavities do not admit of reflections, as convex forms do[16].
[15] Note, though I have advised the observing objects by a front light, for the sake of the better distinguishing our four fundamental species of shades, yet objects in general are more advantagiously, and agreeably seen by light coming side-ways upon them, and therefore generally chose in paintings; as it gives an additional reflected softness, not unlike the gentle tone of an echo in music.
[16] As an instance that convex and concave would appear the same, if the former were to have no reflection thrown upon, observe the ovolo and cavetto, or channel, in a cornice, placed near together, and seen by a front light, when they will each of them, by turns, appear either concave, or convex, as fancy shall direct.
I have now only to add, that as before observed, Chapter IV, page [23], that the oval hath a noble simplicity in it, more equal to its variety than any other object in nature; and of which the general form of a face is composed; therefore, from what has been now shewn, the general gradation-shade belonging to it, must consequently be adequate thereto, and which evidently gives a delicate softness to the whole composition of a face; insomuch that every little dent, crack, or scratch, the form receives, its shadows also suffer with it, and help to shew the blemish. Even the least roughness interrupts and damages that soft gradating play of shades which fall upon it. Mr. Dryden, describing the light and shades of a face, in his epistle to Sir Godfrey Kneller the portrait painter, seems, by the penetration of his incomparable genius, to have understood that language in the works of nature, which the latter, by means of an exact eye and a strict obeying hand, could only faithfully transcribe; when he says,
Where light to shades descending, plays, not strives,
Dies by degrees, and by degrees revives.