here
land is too wet to ditch properly in the first instance, and it is
necessary to draw off part of the surplus water before systematic
operations are commenced--an open ditch is, perhaps, the cheapest method
to be adopted.

Again: where land to be drained is part of a large sloping tract, and
water runs down, at certain seasons, in large quantities upon the
surface, an open catch-water-ditch may be absolutely necessary. This
condition of circumstances is very common in mountainous districts,
where the rain which falls on the hills flows down, either on the
visible surface or on the rock-formation under the soil, and breaks out
at the foot, causing swamps, often high up on the hill-sides. Often,
too, in clay districts, where sand or loam two or three feet deep rests
on tough clay, we see broad sloping tracts, which form our best
grass-fields.

If we are attempting to drain the lower part of such a slope, we shall
find that the water from the upper part flows down in large quantities
upon us, and an open ditch may be most economical as a header, to cut
off the down-flowing water; though, in most cases, a covered drain may
be as efficient.

At the outlets, too, of our tile or stone drains, when we come down
nearly to the level of the stream which receives our drainage-water, we
find it convenient, often, and indeed necessary, to use open
ditches--perhaps only a foot or two deep--to carry off the water
discharged. These ditches are of great importance, and should be
finished with care, because, if they become obstructed, they cause
back-water in the drains, and may ruin the whole work.

Open drains are thus essential auxiliaries to the best plans of thorough
drainage; and, whatever opinion may be entertained of their economy,
many farmers are so situated that they feel obliged to resort to them
for the present, or abandon all idea of draining their wet lands. We
will, therefore, give some hints as to the best manner of constructing
open drains; and then suggest, in the form of objections to them, such
considerations as shall lead the proprietor who adopts this mode to
consider carefully his plan of operations in the outset, with a view to
obviate, as much as possible, the manifest embarrassments occasioned by
them.

As to the location of drains in swamps and peculiarly wet places,
directions may be found in another chapter. We here propose only to
treat of the mode of forming open drains, after their location is f