The name is absent

down very exact general calculations as to the return ob-
tained from plantations of these kinds of timber, so great
is the influence of soil, climate, and position upon the
growth and longevity of the trees. Different authorities
that have made the same estimate from experience of a
forest to be exterminated and renewed in the course of
one hundred years, have arrived at the differing conclu-
sions noted in the figures of the following table. It sup-
poses the term of one hundred years divided into five
periods for felling, at each of which the number of cubic
feet noted in the table shows the growth of the trees
and the planter’s gain. The calculations differ as much
as thirty-three per cent.

According to the calculation of the first-named writer
a morgen of land ought to produce 4655 cubic feet of
timber in a hundred years, -while the second estimates
a growth of 6584 cubic feet in the same inter-
val ; this will show the difficulty of treating the subject
briefly and satisfactorily. These figures are taken from
tables calculated on observations made in different parts of
Germany ; it would be as dangerous, however, to assume
an average of these results as a practical guide in forest
estimates, as it is to attempt to form a general table of
mortality from a combination of scattered materials. The
calculation will in both cases be a safer one if it be con-
fined to the localities from which sure information has
been obtained. When the forester has ascertained the
slow or rapid growth of his timber, and the kind of tim-
ber predominating in his district, he may then apply some
such table as the following to calculate his stock and its
prospects :—

Produce of a Fulda morgen equal to half an acre of
beech-wood, in a course of 120 years :—

Disposable

From column three we see that the annual growth
increases in the beech, under favourable Circumstancesof

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