Knoxville weekly chronicle. [volume] (Knoxville, Tenn.) 1870-1875, 1870-05-11
lCONNuNTcATED.l
EAST TENNESSEE UNIVERSITY.
lecture on AgricuIture.

Lecture ON Agriculture.
At the University, on Friday, Prof Nichol
son delivered his sixth lecture on agriculture
He resumed the subject OF land Drainage,
and began by saying "The object Of drainage
is, to enable the plant to extract the creates
amount Of nourishment from he soil Evapo
ration is the process by which liquid assume
the form of gas Vapor produced by heat
It occupies 1000 times the space of water, and
to do this absorbs the heat Of surrounding
bodies wet napkin on an aching head cools
It, because in evaporating, the water carries of
! the heat Of the adjacent parts. The same may
be said of wet cloth on pitcher of water in a
summer day
" Does this apply to drainage? 1t does The
greater part of the water of undrained lands
must escape by evaporation, and in so doing
carries off a large quantity of the soils heat.
Experiments show that soil drained is 81 degrees
warmer than undraned soil This is equal to a
difference in altitude of 1860 feet 1t is estima-
ted that in England the evaporation is inches
per month from May to August inclusive. Two
inches of water over one acre equals 200 tons
and so must take an immense quantity of heat
from the soil in evaporating Evaporation
makes it almost impossible to obtain warm
soil in wet undrained land. One special object
of draining is to keep the soil warm. If the
water is carried off by drains, no heat is alb
stracted by evaporation
The next great advantage of drainage is to
protect crops from drouth. Some men think
that carrying off the water by drains makes
drouth, This is only one of the many errors.
There is always the same amount of water in
and abount the earth. There is more in the soil
in winter than in summer, for in the latter sea-
son great part of it floats away in the form of
vapor.
"Vapor is preserved by heat Dew is formed
by cold In summer, the soil and plants are
colder than the air, and so condense this vapor
into dew. This same process extends down into
the soil. Now, your land is not drained, wa
ter occupies the openings between the particles
of soil, and, therefore, the air cannot pass down
TO deposit the dew. Dew is much more impor-
tant to crops than is generally supposed. Drain
age makes the soil spongy, SO that it not only
absorbs moisture from the air, but by capillary
attraction draws it up from the subsoi below
Again, drainage effects chemical changes in
the soil. This is illustrated by the changed
character of the red clay thrown up from the nu-
merous rife-pts around Knoxville, which, from
being barren soon becomes highly productive
Also, draining incorporates manure with the
soil. In undraded soils, the manure cannot go
below depth of five or six inches and its good
effect is soon lost; while in drained lands, it
goes down three four feet, and forms a re-
serve for years. The health of man and animals
is effected by drainage. We know swamps pro-
duce chlls and fever to a proportional extent
damp soil Injuries animals. Physicians have
that many cases of consumption are
induced by defect Of drainage around dwell
ings
'Drainages is subject almost entirely neglect
ed by farmers. They doubt the utility of it
W hen anything was proposed to the ancient
Hebrews, they asked. Did God command it?n
If to the Greeks, they inquired, is it beauti-
ful?' The Romans, rs it lawful?' If in our
own day, to the French, they ask, 'Is it glori-
Gus or witty?' The English rs it customary
with the nobility But Americans say, "Wil
it pay?' They worship the almighty dollar.
Talk draining as eloquent as Demosthenese, and
If you don't show that it pays you fail TO effect
anything. Ny answer is that it will pay on all
land that needs draining And now will it pay
In the first place it gives the farmer command
OF his land. He can plant at his own time,
almost regardless of weather 1t has been prov
ed that 1t greatly increases the yield of crops.
In undrained lands a great many of the seed
planted do not come up"
Here the results of some experiments were
given to show the great advantage of draining.
The subject of next lecture will be-" Flows
and Flowing"