circulation of air among the wide fissures between them. It is also
worthy of incidental remark, that the cracking of heavy soils, shrinking
by drought, is attended by the tearing asunder of the smaller roots which
may have penetrated them.

*The Injurious Effects of Standing Water in the Subsoil* may be best
explained in connection with the description of a soil which needs
under-draining. It would be tedious, and superfluous, to attempt to detail
the various geological formations and conditions which make the soil
unprofitably wet, and render draining necessary. Nor,--as this work is
intended as a hand-book for practical use,--is it deemed advisable to
introduce the geological charts and sections, which are so often employed
to illustrate the various sources of under-ground water; interesting as
they are to students of the theories of agriculture, and important as the
study is, their consideration here would consume space, which it is
desired to devote only to the reasons for, and the practice of,
thorough-draining.

To one writing in advocacy of improvements, of any kind, there is always a
temptation to throw a tub to the popular whale, and to suggest some
make-shift, by which a certain advantage may be obtained at half-price. It
is proposed in this essay to resist that temptation, and to adhere to the
rule that "whatever is worth doing, is worth doing well," in the belief
that this rule applies in no other department of industry with more force
than in the draining of land, whether for agricultural or for sanitary
improvement. Therefore, it will not be recommended that draining be ever
confined to the wettest lands only; that, in the pursuance of a
penny-wisdom, drains be constructed with stones, or brush, or boards; that
the antiquated horse-shoe tiles be used, because they cost less money; or
that it will, in any case, be economical to make only such drains as are
necessary to remove the water of large springs. The doctrine herein
advanced is, that, so far as draining is applied at all, it should be done
in the most thorough and complete manner, and that it is better that, in
commencing this improvement, a single field be really well drained, than
that the whole farm be half drained.

Of course, there are some farms which suffer from too much water, which
are not worth draining at present; many more which, at the present price
of frontier lands, are only worth relieving of the water which stands on
the surface;