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PATTERSON v. M'CAUSLAND. 91
From what has been said, it appears, then, that some mere an-
nual roots, and the roots of all trees, as well as the wood of most
of our forest trees, exhibit the appearance, in a transverse section,
of having been formed by a succession of concentrical layers; that
the wood of a variety of trees which are only the growth of the
torrid zone, are obviously formed in the same way: and therefore,
that such concentrical layers cannot with certainty be pronounced
to be the result of a succession of summer growths; or any one of
them to be the growth of only one year, or of any other given
space of time. It also appears, that the wood of some trees, of
the growth of the temperate as well as of the torrid zone, does
not, in a transverse section of it, exhibit the least appearance
whatever of any concentrical layers; and that in the wood of
those trees, which is so constructed, the formation of such layers
is said to be checked by accident, to be much affected by soil and
situation, and even by the peculiarities of the successive seasons;
and moreover, that they always become thinner and more indis-
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been drained of three feet of its usual contents, still, on the 25th of August, con-
tained water, A chesnut tree, six feet in diameter, standing on the top of the
wall, serves to mark its antiquity. Counting and measuring the annual layers of
wood, where an axeman had cut into the trunk, I found them at nearly two hundred
to the foot, which would give to this tree six hundred years. How much longer
the wall had been standing, I saw no means of determining. A poplar, seven feet
in diameter, standing in the ditch, allowing the thickness to the layers which I have
found in like poplars, one hundred and seventy to the foot, would give nearly the
same result, six hundred and seven years.'—The Globe newspaper, 2lst Sept, 1838.
* There have,' says Goldsmith,' been two methods devised for determining the age
of fishes, which are more ingenious than certain; the one is the circles of the
scales, the other by the transverse section of the backbone. The first method is
this. When the fish's scale is examined, through a microscope, it will be found to
consist of a number of circles, one circle within another, in some measure resem-
bling those which appear upon the transverse section of a tree, and supposed to
offer the same information. For, as in trees we can tell their age by the number of
their circles, so in fishes we can tell theirs by the number of circles in every scale,
reckoning one ring for every year of the animal's existence. By this method, M.
Button found a carp, whose scales he examined, to be not less than a hundred years
old; a thing almost incredible, had we not several accounts in other authors which
tend to confirm the discovery. Gesner brings us an instance of one of the same
age; and Albertus of one more than double that period. The age of the skate and
ray, that want scales, may be known by the other method; which is by separating
the joints of the backbone, and then minutely observing the number of rings which
the surface where it was joined exhibits. By this the fish's age is said to be known;
and perhaps with as much certainty as in the former instance. But how unsatis-
factory soever these marks may be, we have no reason to doubt the great age of
some fishes. Those that have ponds often know the oldest by their superior size.'
Goldsmith's Animated Nature, Hist. Fishes chap, 1.
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