223. One of the most important applications of the law of contrast is in association with the law of continuity, causing an unexpected but gentle break in a continuous series. This artifice is perpetual in music, and perpetual also in good illumination; the way in which little surprises of change are prepared in any current borders, or chains of ornamental design, being one of the most subtle characteristics of the work of the good periods. We take, for instance, a bar of ornament between two written columns of an early fourteenth century MS., and at the first glance we suppose it to be quite monotonous all the way up, composed of a winding tendril, with alternately a blue leaf and a scarlet bud. Presently, however, we see that, in order to observe the law of principality, there is one large scarlet leaf instead of a bud, nearly half-way up, which forms a center to the whole rod; and when we begin to examine the order of the leaves, we find it varied carefully. Let A stand for scarlet bud, b for blue leaf, c for two blue leaves on one stalk, s for a stalk without a leaf, and R, for the large red leaf. Then, counting from the ground, the order begins as follows:
b, b, A; b, s, b, A; b, b, A; b, b, A; and we think we shall have two b's and an A all the way, when suddenly it becomes b, A; b, R; b, A; b, A; b, A; and we think we are going to have b, A continued; but no: here it becomes b, s; b, s; b, A; b, s; b, s; c, s; b, s; b, s; and we think we are surely going to have b, s continued, but behold it runs away to the end with a quick b, b, A; b, b, b, b![69] Very often, however, the designer is satisfied with one surprise, but I never saw a good illuminated border without one at least; and no series of any kind was ever introduced by a great composer in a painting without a snap somewhere. There is a pretty one in Turner's drawing of Rome with the large balustrade for a foreground in the Hakewell's Italy series: the single baluster struck out of the line, and showing the street below through the gap, simply makes the whole composition right, when otherwise it would have been stiff and absurd.
224. If you look back to [Fig. 48] you will see, in the arrangement of the battlements, a simple instance of the use of such variation. The whole top of the tower, though actually three sides of a square, strikes the eye as a continuous series of five masses. The first two, on the left, somewhat square and blank, then the next two higher and richer, the tiles being seen on their slopes. Both these groups being couples, there is enough monotony in the series to make a change pleasant; and the last battlement, therefore, is a little higher than the first two,—a little lower than the second two,—and different in shape from either. Hide it with your finger, and see how ugly and formal the other four battlements look.
225. There are in this figure several other simple illustrations of the laws we have been tracing. Thus the whole shape of the walls' mass being square, it is well, still for the sake of contrast, to oppose it not only by the element of curvature, in the ring, and lines of the roof below, but by that of sharpness; hence the pleasure which the eye takes in the projecting point of the roof. Also, because the walls are thick and sturdy, it is well to contrast their strength with weakness; therefore we enjoy the evident decrepitude of this roof as it sinks between them. The whole mass being nearly white, we want a contrasting shadow somewhere; and get it, under our piece of decrepitude. This shade, with the tiles of the wall below, forms another pointed mass, necessary to the first by the law of repetition. Hide this inferior angle with your finger, and see how ugly the other looks. A sense of the law of symmetry, though you might hardly suppose it, has some share in the feeling with which you look at the battlements; there is a certain pleasure in the opposed slopes of their top, on one side down to the left, on the other to the right. Still less would you think the law of radiation had anything to do with the matter: but if you take the extreme point of the black shadow on the left for a center, and follow first the low curve of the eaves of the wall, it will lead you, if you continue it, to the point of the tower cornice; follow the second curve, the top of the tiles of the wall, and it will strike the top of the right-hand battlement; then draw a curve from the highest point of the angled battlement on the left, through the points of the roof and its dark echo; and you will see how the whole top of the tower radiates from this lowest dark point. There are other curvatures crossing these main ones, to keep them from being too conspicuous. Follow the curve of the upper roof, it will take you to the top of the highest battlement; and the stones indicated at the right-hand side of the tower are more extended at the bottom, in order to get some less direct expression of sympathy, such as irregular stones may be capable of, with the general flow of the curves from left to right.
226. You may not readily believe, at first, that all these laws are indeed involved in so trifling a piece of composition. But, as you study longer, you will discover that these laws, and many more, are obeyed by the powerful composers in every touch: that literally, there is never a dash of their pencil which is not carrying out appointed purposes of this kind in twenty various ways at once; and that there is as much difference, in way of intention and authority, between one of the great composers ruling his colors, and a common painter confused by them, as there is between a general directing the march of an army, and an old lady carried off her feet by a mob.
7. THE LAW OF INTERCHANGE.
227. Closely connected with the law of contrast is a law which enforces the unity of opposite things, by giving to each a portion of the character of the other. If, for instance, you divide a shield into two masses of color, all the way down—suppose blue and white, and put a bar, or figure of an animal, partly on one division, partly on the other, you will find it pleasant to the eye if you make the part of the animal blue which comes upon the white half, and white which comes upon the blue half. This is done in heraldry, partly for the sake of perfect intelligibility, but yet more for the sake of delight in interchange of color, since, in all ornamentation whatever, the practice is continual, in the ages of good design.
228. Sometimes this alternation is merely a reversal of contrasts; as that, after red has been for some time on one side, and blue on the other, red shall pass to blue's side and blue to red's. This kind of alternation takes place simply in four-quartered shields; in more subtle pieces of treatment, a little bit only of each color is carried into the other, and they are as it were dovetailed together. One of the most curious facts which will impress itself upon you, when you have drawn some time carefully from Nature in light and shade, is the appearance of intentional artifice with which contrasts of this alternate kind are produced by her; the artistry with which she will darken a tree trunk as long as it comes against light sky, and throw sunlight on it precisely at the spot where it comes against a dark hill, and similarly treat all her masses of shade and color, is so great, that if you only follow her closely, every one who looks at your drawing with attention will think that you have been inventing the most artificially and unnaturally delightful interchanges of shadow that could possibly be devised by human wit.
229. You will find this law of interchange insisted upon at length by Prout in his Lessons on Light and Shade: it seems of all his principles of composition to be the one he is most conscious of; many others he obeys by instinct, but this he formally accepts and forcibly declares.
The typical purpose of the law of interchange is, of course, to teach us how opposite natures may be helped and strengthened by receiving each, as far as they can, some impress or reflection, or imparted power, from the other.