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the best preventive against the flooding of heavy rains, because the water 
can enter the soil, and pass away by the natural channels, instead of 
overflowing the surface; and, again, in the subsoil are found all the ele¬ 
ments of fertility which the soil possessed before it was weakened by re¬ 
peated cropping. 
The Improvement of Soils —Is a modification of their original natural 
qualities, to better adapt them to the climate or to the crops they are in¬ 
tended to produce. Observation shows, that soils with a due proportion 
of sand and clay are the best adapted to the general uses of agriculture, 
but seldom are these two ingredients found united in the proper propor¬ 
tion, either the one or the other predominates; and the most natural in¬ 
ference is, that a mechanical intermixture would be the proper method of 
amelioration. No doubt that a heavy clay soil would be materially bene- 
fitted by the addition of a quantity of sand, and that a loose sand would 
be made more productive by an intermixture with clay soil ; for the co¬ 
hesiveness of a clay soil (says the theorist) would be overcome in a great 
measure by the sand—it would dry earlier and retain the heat better; and 
so, on the other hand, sandy soils are too loose and possess too little cohe¬ 
siveness—now, introduce clay as a cement, and your soil is perfect: neither 
too loose nor yet too cohesive. But this theory, which at first sight appears 
so natural, is obnoxious to a weighty objection, its expensiveness and the 
same ends can be obtained equally well, by simpler and far cheaper means. 
[Note. —For some crops stiff soils are preferable, while others require the op¬ 
posite, and we can generally decide from the roots of the plant what kind of soil 
is best adapted to its culture. Plants with large, or largely developed, roots, re¬ 
quire a loose soil, well stirred—for instance, turnips, carrots, potatoes, and Indian 
corn; while wheat, and the grasses, flourish best in a soil of more consistency. 
But the skillful agriculturist will not only understand the wants of crops, and 
the nature of his soil, but he will also investigate the means of improving his 
domain—he must not rest satisfied with the good qualities of his farm, but 
must study its defects and how to apply the remedy, and be guided both by his 
own observation and experience, and that of others; always endeavoring to add 
to the general fund of knowledge by continued and careful experiment.] 
Sandy soils, for instance, are unable to retain sufficient moisture, and 
we overcome this defect, not by an intermixture of clay, as theory would 
do, but by manures capable of retaining moisture in a high degree—for 
instance, humus or vegetable mould, which possesses, as we have before 
i 
