re entitled to the original
fertility of the soil. Europe passed through the process of settlement
and exhaustion many centuries ago. Her recovery has been the work of
centuries,--ours may be accomplished in a few years, even within the
limits of a single life. The fact from which an improving system of
agriculture must proceed is apparent in the northern and central
Atlantic states, and is, in a measure, appreciated in the West. We have
all heard that certain soils were inexhaustible. The statement was first
made of the valley of the Connecticut, then of the Genesee country, then
of Ohio, then of Illinois, and occasionally we now hear similar
statements of Kansas, or California, or the valley of the Willamette. In
the nature of things these statements were erroneous. The idea of soil,
in reason and in the use of the word, contains the idea of exhaustion.
Soil is not merely the upper stratum of the earth; it is a substance
which possesses the power, under certain circumstances, of giving up
essential properties of its own for the support of vegetable and
ultimately of animal life. What it gives up it loses, and to the extent
of its loss it is exhausted. It is no more untrue to say that the great
cities of the world have not, in their building, exhausted the forests
and the mines to any extent, than to say that the annual abundant
harvests of corn and wheat have not, in any degree, exhausted the
prairies and bottom lands of the West. Some lands may be exhausted for
particular crops in a single year; others in five years, others in ten,
while others may yield undiminished returns for twenty, fifty, or even a
hundred years. But it is plain that annual cropping without rotation,
and without compensation by nature or art, must finally deprive the soil
of the required elements. Nor should we deceive ourselves by considering
only those exceptions whose existence is due to the fact that nature
makes compensation for the loss. Annual or occasional irrigation with
rich deposits,--as upon the Nile and the Connecticut,--allowing the
land to lie fallow, rotation of crops and the growth of wood, are so
many expedients and provisions by which nature increases the
productiveness of the earth. Nor is a great depth of soil, as two, five,
ten, or twenty feet, any security against its ultimate impoverishment.
Only a certain portion is available. It has been found in the case of
coal-mines which lie at great depths, that they are, for the pre