§ 10. Wherein we already see the germ of our irregularly bending branch, which might ultimately be much the prettier for the loss of _b_. Alas! the Fates have forbidden even this. While the low bough is making all these exertions, the boughs of A, above him, higher in air, have made the same under happier auspices. Every year their thicker leaves more and more forbid the light; and, after rain, shed their own drops unwittingly on the unfortunate lower bough, and prevent the air or sun from drying his bark or checking the chill in his medullary rays. Slowly a hopeless languor gains upon him. He buds here or there, faintly, in the spring; but the flow of strong wood from above oppresses him even about his root, where it joins the trunk. The very sap does not turn aside to him, but rushes up to the stronger, laughing leaves far above. Life is no more worth having; and abandoning all effort, the poor bough drops, and finds consummation of destiny in helping an old woman's fire. When he is gone, the one next above is left with greater freedom, and will shoot now from points of its sprays which were before likely to perish. Hence another condition of irregularity in form. But that bough also will fall in its turn, though after longer persistence. Gradually thus the central trunk is built, and the branches by whose help it was formed cast off, leaving here and there scars, which are all effaced by years, or lost sight of among the roughnesses and furrows of the aged surface. The work is continually advancing, and thus the head of foliage on any tree is not an expansion at a given height, like a flower-bell, but the collective group of boughs, or workmen, who have got up so far, and will get up higher next year, still losing one or two of their number underneath. § 11. So far well. But this only accounts for the formation of a vertical trunk. How is it that at a certain height this vertical trunk ceases to be built; and irregular branches spread in all directions?