§ 19. Before the idea of landscape had been thus far developed, the representations of it had been purely typical; the objects which had to be shown in order to explain the scene of the event, being firmly outlined, usually on a pure golden or chequered color background, not on sky. The change from the golden background, (characteristic of the finest thirteenth century work) and the colored chequer (which in like manner belongs to the finest fourteenth) to the blue sky, gradated to the horizon, takes place early in the fifteenth century, and is the crisis of change in the spirit of mediæval art. Strictly speaking, we might divide the art of Christian times into two great masses—Symbolic and Imitative;—the symbolic, reaching from the earliest periods down to the close of the fourteenth century, and the imitative from that close to the present time; and, then, the most important circumstance indicative of the culminating point, or turn of tide, would be this of the change from chequered background to sky background. The uppermost figure in Plate 7. opposite, representing the tree of knowledge, taken from a somewhat late thirteenth century Hebrew manuscript (Additional 11,639) in the British Museum, will at once illustrate Mr. Macaulay's "serpent turned round the tree," and the mode of introducing the chequer background, will enable the reader better to understand the peculiar feeling of the period, which no more intended the formal walls or streams for an imitative representation of the Garden of Eden, than these chequers for an imitation of sky.
§ 20. The moment the sky is introduced (and it is curious how perfectly it is done at once, many manuscripts presenting, in alternate pages, chequered backgrounds, and deep blue skies exquisitely gradated to the horizon)—the moment, I say, the sky is introduced, the spirit of art becomes for evermore changed, and thenceforward it gradually proposes imitation more and more as an end, until it reaches the Turnerian landscape. This broad division into two schools would therefore be the most true and accurate we could employ, but not the most convenient. For the great mediæval art lies in a cluster about the culminating point, including symbolism on one side, and imitation on the other, and extending like a radiant cloud upon the mountain peak of ages, partly down both sides of it, from the year 1200 to 1500; the brightest part of the cloud leaning a little backwards, and poising itself between 1250 and 1350. And therefore the most convenient arrangement is into Romanesque and barbaric art, up to 1200,—mediæval art, 1200 to 1500,—and modern art, from 1500 downwards. But it is only in the earlier or symbolic mediæval art, reaching up to the close of the fourteenth century, that the peculiar modification of natural forms for decorative purposes is seen in its perfection, with all its beauty, and all its necessary shortcomings; the minds of men being accurately balanced between that honor for the superior human form which they shared with the Greek ages, and the sentimental love of nature which was peculiar to their own. The expression of the two feelings will be found to vary according to the material and place of the art; in painting, the conventional forms are more adopted, in order to obtain definition, and brilliancy of color, while in sculpture the life of nature is often rendered with a love and faithfulness which put modern art to shame. And in this earnest contemplation of the natural facts, united with an endeavor to simplify, for clear expression, the results of that contemplation, the ornamental artists arrived at two abstract conclusions about form, which are highly curious and interesting.
§ 21. They saw, first, that a leaf might always be considered as a sudden expansion of the stem that bore it; an uncontrollable expression of delight, on the part of the twig, that spring had come, shown in a fountain-like expatiation of its tender green heart into the air. They saw that in this violent proclamation of its delight and liberty, whereas the twig had, until that moment, a disposition only to grow quietly forwards, it expressed its satisfaction and extreme pleasure in sunshine by springing out to right and left. Let a b, Fig. 1. Plate 8., be the twig growing forward in the direction from a to b. It reaches the point b, and then—spring coming,—not being able to contain itself, it bursts out in every direction, even springing backwards at first for joy; but as this backward direction is contrary to its own proper fate and nature, it cannot go on so long, and the length of each rib into which it separates is proportioned accurately to the degree in which the proceedings of that rib are in harmony with the natural destiny of the plant. Thus the rib c, entirely contradictory, by the direction of his life and energy, of the general intentions to the tree, is but a short-lived rib; d, not quite so opposite to his fate, lives longer; e, accommodating himself still more to the spirit of progress, attains a greater length still; and the largest rib of all is the one who has not yielded at all to the erratic disposition of the others when spring came, but, feeling quite as happy about the spring as they did, nevertheless took no holiday, minded his business, and grew straightforward.
§ 22. Fig. 6. in the same plate, which shows the disposition of the ribs in the leaf of an American Plane, exemplifies the principle very accurately; it is indeed more notably seen in this than in most leaves, because the ribs at the base have evidently had a little fraternal quarrel about their spring holiday; and the more gaily-minded ones, getting together into trios on each side, have rather pooh-poohed and laughed at the seventh brother in the middle, who wanted to go on regularly, and attend to his work. Nevertheless, though thus starting quite by himself in life, this seventh brother, quietly pushing on in the right direction, lives longest, and makes the largest fortune, and the triple partnerships on the right and left meet with a very minor prosperity.
§ 23. Now if we inclose Fig. 1. in Plate 8. with two curves passing through the extremities of the ribs, we get Fig. 2., the central type of all leaves. Only this type is modified of course in a thousand ways by the life of the plant. If it be marsh or aquatic, instead of springing out in twigs, it is almost certain to expand in soft currents, as the liberated stream does at its mouth into the ocean, Fig. 3. (Alisma Plantago); if it be meant for one of the crowned and lovely trees of the earth, it will separate into stars, and each ray of the leaf will form a ray of light in the crown, Fig. 5. (Horsechestnut); and if it be a commonplace tree, rather prudent and practical than imaginative, it will not expand all at once, but throw out the ribs every now and then along the central rib, like a merchant taking his occasional and restricted holiday, Fig. 4. (Elm).
§ 24. Now in the bud, where all these proceedings on the leaf's part are first imagined, the young leaf is generally (always?) doubled up in embryo, so as to present the profile of the half-leaves, as Fig. 7., only in exquisite complexity of arrangement; Fig. 9., for instance, is the profile of the leaf-bud of a rose. Hence the general arrangement of line represented by Fig. 8. (in which the lower line is slightly curved to express the bending life in the spine) is everlastingly typical of the expanding powers of joyful vegetative youth; and it is of all simple forms the most exquisitely delightful to the human mind. It presents itself in a thousand different proportions and variations in the buds and profiles of leaves; those being always the loveliest in which, either by accidental perspective of position, or inherent character in the tree, it is most frequently presented to the eye. The branch of bramble, for instance, Fig. 10. at the bottom of Plate 8., owes its chief beauty to the perpetual recurrence of this typical form; and we shall find presently the enormous importance of it, even in mountain ranges, though, in these, falling force takes the place of vital force.