This field was
drained in March, 1842, to the depth of 30 to 36 inches, at a distance of
24 feet asunder, the length of each drain being 235 yards.
"Each, drain emptied itself through a fence bank into a running stream in
a road below it; the discharge therefore was distinctly observable. Two or
three of the pipes had now ceased running; and, with the exception of one
which tapped a small spring and gave a stream about the size of a tobacco
pipe, the run from the others did not exceed the size of a wheat straw.
The greatest flow had been observed by Mr. Hammond at no time to exceed
half the bore of the pipes. The fall in this field is very great, and the
drains are laid in the direction of the fall, which has always been the
practice in this district. The issuing water was transparently clear; and
Mr. Hammond states that he has never observed cloudiness, except for a
short time after very heavy flushes of rain, when the drains are quickly
cleared of all sediment, in consequence of the velocity and force of the
water passing through so small a channel. Infiltration through the soil
and into the pipes, must, in this case, be considered to have been
perfect; and their observed action is the more determinate and valuable as
regards time and effect, as the land was saturated with moisture previous
to this particular fall of rain, and the pipes had ceased to run when it
commenced. This piece had, previous to its drainage, necessarily been
cultivated in narrow stretches, with an open water furrow between them;
but it was now laid quite plain, by which one-eighth of the continuation
of acreage has been saved.
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