pear, in the course of this work, the only sort
of drain to which reference is here made is that which consists of a
conduit of burned clay, (tile,) placed at a considerable depth in the
subsoil, and enclosed in a compacted bed of the stiffest earth which can
conveniently be found. Stone-drains, brush-drains, sod-drains, mole-plow
tracks, and the various other devices for forming a conduit for the
conveying away of the soakage-water of the land, are not without the
support of such arguments as are based on the expediency of make-shifts,
and are, perhaps, in rare cases, advisable to be used; but, for the
purposes of permanent improvement, they are neither so good nor so
economical as tile-drains. The arguments of this book have reference to
the latter, (as the most perfect of all drains thus far invented,) though
they will apply, in a modified degree, to all underground conduits, so
long as they remain free from obstructions. Concerning stone-drains,
attention may properly be called to the fact that, (contrary to the
general opinion of farmers,) they are very much more expensive than
tile-drains. So great is the cost of cutting the ditches to the much
greater size required for stone than for tiles, of handling the stones, of
placing them properly in the ditches, and of covering them, after they are
laid, with a suitable barrier to the rattling down of loose earth among
them, that, as a mere question of first cost, it is far cheaper to buy
tiles than to use stones, although these may lie on the surface of the
field, and only require to be placed in the trenches. In addition to this,
the great liability of stone-drains to become obstructed in a few years,
and the certainty that tile-drains will, practically, last forever, are
conclusive arguments in favor of the use of the latter. If the land is
stony, it must be cleared; this is a proposition by itself, but if the
sole object is to make drains, the best material should be used, and this
material is not stone.

A well laid tile-drain has the following essential characteristics:--1. It
has a free outlet for the discharge of all water which may run through it.
2. It has openings, at its joints, sufficient for the admission of all the
water which may rise to the level of its floor. 3. Its floor is laid on a
well regulated line of descent, so that its current may maintain a flow of
uniform, or, at least, never decreasing rapidity, throughout its entire
length.

Land which req