For this multiplication of the cells is at least compelled
by an influence which passes from the leaf to the ground, and vice versa;
and which is at present best {168} conceivable to me by imagining the
continual and invisible descent of lightning from electric cloud by a
conducting rod, endowed with the power of softly splitting the rod into two
rods, each as thick as the original one. Studying microscopically, we
should then see the molecules of copper, as we see the cells of the wood,
dividing and increasing, each one of them into two. But the visible result,
and mechanical conditions of growth, would still be the same as if the leaf
actually sent down a new root fibre; and, more than this, the currents of
accumulating substance, marked by the grain of the wood, are, I think,
quite plainly and absolutely those of streams flowing only from the leaves
downwards; never from the root up, nor of mere lateral increase. I must
look over all my drawings again, and at tree stems again, with more
separate study of the bark and pith in those museum sections, before I can
assert this; but there will be no real difficulty in the investigation. If
the increase of the wood is lateral only, the currents round the knots will
be compressed at the sides, and open above and below; but if downwards,
compressed above the knot and open below it. The nature of the force
itself, and the manner of its ordinances in direction, remain, and must for
ever remain, inscrutable as our own passions, in the hand of the God of all
Spirits, and of all Flesh.

"Drunk is each ridge, of thy cup drinking,
Each clod relenteth at thy dressing,
{169}
Thy cloud-borne waters inly sinking,
Fair spring sproutes forth, blest with thy blessing;
The fertile year is with thy bounty crouned,
And where thou go'st, thy goings fat the ground.

Plenty bedews the desert places,
A hedge of mirth the hills encloseth.
The fields with flockes have hid their faces,
A robe of corn the valleys clotheth.
Deserts and hills and fields and valleys all,
Rejoice, shout, sing, and on thy name do call."

* * * * *

{170}

CHAPTER X.

THE BARK.

1. Philologists are continually collecting instances, like our friend the
French critic of Virgil, of the beauty of finished language, or the origin
of unfinished, in the imitation of natural sounds. But such collections
give an entirely false idea