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84 PATTERSON v. M'CAUSLAND.
Supposing it to be true, that all our forest trees are sustained
only by the circulation earned on immediately under their bark,
disturbing it. Third, the origin of the wood is in some way intimately connected
with the action of the leaves. It has long been known, that the diameter of a stem
depends very much upon the number of the leaves which it bears; and that the
larger the number of leaves developed upon a stem, the greater will be its diameter,
and the more rapid its growth. And also, that the largest quantity of wood is
always found on that side of a stem which developes most leaves. But had we only
these facts, on which to base a judgment, we might hesitate which to consider the
cause and which the effect; whether to believe that the luxuriance of the stem arose
from the increased number of the leaves, or the increased number of leaves from the
luxuriance of the stem. This question, however, has been determined by direct
experiment. Mr. Knight stripped off the leaves from the upper portion of a young
shoot; as the consequence, the shoot died as far down as the leaves were removed,
whilst below that point, it flourished. He afterwards insulated a single leaf, by re-
moving a ring of bark, at some distance above the point at which it was inserted
into the stem, and another at an equal distance below that point. In the course of
the summer a perceptible increase in the wood took place above the leaf, but none
below it. In another instance, he removed a narrow ring of bark from the lower
part of a growing stem; the stem afterwards increased sensibly in diameter down to
this ring; but not at all between the ring and the leaf next below it. From these
and similar facts he has inferred, that the matter of which the wood is formed, is
elaborated in the leaves and sent downwards. Fourth, the portion of wood formed
each year, is entirely independent of, and distinct from, that of every other year;
and when once formed, undergoes no change, except the slight change which takes
place when it is converted from sapwood into he art wood. In confirmation of this,
many curious facts may be mentioned. On what are called line trees,' in the west,
certain marks are made when the land is first divided off into lots. This is done by
striking with an axe, so as to cut through the bark and two or three of the outer
layers of the wood. If one of those trees be examined, say twenty years after the
marks were made, no traces of them will be discovered on the outside of the bark;
nor, if we cut into the wood, will we find any on the nineteen outer layers; whilst
we will find all the marks perfect in the twentieth layer, in which they were ori-
ginally made; thus establishing the fact, that that layer has remained unaltered since
its first formation, and that all the outer layers have been formed entirely indepen-
dent of it. Good, in bis Book of Nature, states, that in England, dates of very re-
mote national eras, and the initials of monarchs who flourished in early times, have
been found stamped in the very heart of the timber. M. Klein states, that in the
year 1727, a long series of letters were discovered in the trunk of a full grown
beech, near Dantzic. The letters were conspicuous in a layer about half way be-
tween the axis and the bark of the stern, whilst no traces of them could be disco*
vered, either in the layers within, or on those without it. The same author mentions
several other facts of the same kind. In one instance, the image of a thief banging
from m gibbet, was discovered in the timber of a beech tree, apparently drawn by
nature's own pencil. In another tree, the figure of a crucified man was found in
similar circumstances; and in another, a chalice, with a sword perpendicularly erect,
sustaining & crown on its point. Such marks were formerly attributed to miraculous
intervention, or regarded as miraculous sports of nature; and on this account, were
preserved with peculiar care. When rightly understood, they place the truth of the
above statement beyond a doubt.'—Essay on Vegetable Physiology, by Armstrong,
Prof, &c., Washington, Virginia, chap, 7; The Farmers' Register, by Ruffin, vol. 7,
No. 4.
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