| Fig. 43. |
§ 12. It may, perhaps, be interesting to compare, with the rude fallacies of Claude and Salvator, a little piece of earliest art, wrought by men who could see and feel. The scroll, Fig. 42, is a portion of that which surrounds the arch in San Zeno of Verona, above the pillar engraved in the Stones of Venice, Plate 17, Vol. I. It is, therefore, twelfth, or earliest thirteenth century work. Yet the foliage is already full of spring and life; and in the part of the stem, which I have given of its real size in Fig. 43, the reader will perhaps be surprised to see at the junctions the laws of vegetation, which escaped the sight of all the degenerate landscape-painters of Italy, expressed by one of her simple architectural workmen six hundred years ago.
We now know enough, I think, of the internal conditions which regulate tree-structure to enable us to investigate finally, the great laws of branch and stem aspect. But they are very beautiful; and we will give them a separate chapter.
[1] See the note on Fig. 11, at page 17, which shows these two directions in a shoot of lime.
[2] I find that the office and nature of cambium, the causes of the action of the sap, and the real mode of the formation of buds, are all still under the investigation of botanists. I do not lose time in stating the doubts or probabilities which exist on these subjects. For us, the mechanical fact of the increase of thickness by every leaf’s action is all that needs attention. The reader who wishes for information as accurate as the present state of science admits, may consult Lindley’s Introduction to Botany, and an interesting little book by Dr. Alexander Harvey on Trees and their Nature (Nisbet & Co., 1856), to which I owe much help.
[3] In the true sense a “mediator,” (μεσίτης).
[4] The gradual development of this radiating structure, which is organic and essential, composed of what are called by botanists medullary rays, is still a great mystery and wonder to me.
