Instead of the few very deep drains, cut with reference to particular
springs or sources of wetness, adopted by Elkington, Smith advocated and
practiced a systematic operation over the whole field, at regular
distances and shallow depths. Smith states, that in Scotland, much more
injury arises from the retention of rain water, than from springs; while
Elkington's attention seems to have been especially directed to springs,
as the source of the evil.

The characteristic views of Smith, of Deanston, as stated by Mr. Denton,
were:

"1st. _Frequent_ drains at intervals of from ten to twenty-four
feet.

"2nd. _Shallow_ depth--not exceeding thirty inches--designed for
the single purpose of freeing that depth of soil from stagnant and
injurious water.

"3rd. '_Parallel drains at regular distances_ carried throughout
the whole field, without reference to the wet and dry appearance of
portions of the field,' in order 'to provide frequent opportunities
for the water, _rising from_ below and falling on the surface, to
pass freely and completely off.

"4th. _Direction of the minor drains_ 'down the steep,' and that of
the mains along the bottom of the chief hollow; tributary mains
being provided for the lesser hollows.

"The reason assigned for the minor drains following the line of
steepest descent, was, that 'the stratification generally lies in
sheets at an angle to the surface.'

"5th. _As to material_--Stones preferred to tiles and pipes."

Mr. Smith somewhat modified his views during the last years of his life,
especially as to the depth of drains, and, instead of shallow drains,
recommended a depth of three feet, and even more in some cases; but
continued, to the time of his death, which occurred about 1854, to
oppose any increased intervals between the drains, and the extreme depth
of four feet and more advocated by others. The peculiar points insisted
on by Smith were, that drains should be near and parallel. His own words
are:

"The drains should be parallel with each other and at regular
distances, and should be carried throughout the whole field,
without regard to the wet and dry appearance of portions of the
field--the principle of this system being the providing of frequent
opportunities for the water rising from below, or falling on the
surface, to pass freely and completely off."

Mr. Sm