The Tupelo journal. (Tupelo, Miss.) 1876-1924, 1907-06-28

nave Deon replaced with DeauCf-
ful homes and commodious barns
and the value of the land in
creased from $1.00 to $10O. 90 and
even $4,000 an acre.
MECHANICAL EFFECTS.
l. Saves space used in turn
ing rows.
2. Prevents woods from
growing.
8. Open bitches are in the way
for hauling and are traps for
stock.
A. Water in the bitches car
ries off the fine particles of fer
tile soil and thus impoverishes
the ground, while tile drainage
carries off the excess of water
through the tile without loss of
the soils fertility.
CHEMICAL EFFECTS.
l. Deeply laid tile drains re-
lieve the soil of free water which.
if it remains for any length of
time, Injuries the growing crops
and causes a concentration of
the iron oxide into small buck
shot pebbles.
/ 2. Well laid tile drains deep
en- the soil bed which retains the
water of moisture and is thus a
protection against drought by
preventing excessive surface
evaporation.
3. Rainfall usually contains
ammonia equal to 6 or s pounds
of nitrogen to the acre, In un-
drained land this valuable fer
tilizer is carried away with the
surface waters. In tile drained
land it is carried into the open
soil by the water and left to be
taken up as plant food.
4. The rainwater instead of
running off passes through the
open soil and carries into it any
applied fertilizer, and serves a
most useful purposei in dissolving
the soil and preparing it for
plant food.
SIZE OF TILE.
The size of tile for the main
drains depends upon the size of
the area to be drained, the
amount of rainfall, the gradient
or fall and the depth the tile are
placed under the ground. It is
evident, therefore, that a large
area with a heavy rainfall would
require a much larger tile than
the same sized area with a scan
, ty rainfall or a smaller area with
smaller rainfall. This question
must be decided by the drainage
engineer.
Formerly two and three inch
tile were the more common sizes
for lateral drains, but in more
recent years there is a growing
! tendency to use a larger tile. In
many sections of the country 4
inch tile are the minimum size
used.
The character Of the soil in the
Yazoo delta and northeast Ar
kansas and the heavy rainfall
which often visits this region
will perhaps require a 4 inch tile
as a minimum; a 5 or 6 inch or
even an 8 inch would not be tee
large in some soils.
| DEPTHS OF DRAINS.
Many of the best engineers
say that tile should not be laid
less than 3 feet deep; others ad.
vocate minimum of 4 feet. A
drain A feet deep will drain ef-
fectively Is per cent wider area
than a drain 3 feet deep. The
extra cost in laying tile at a depth
of 4 feet will be more than off
set in the larger area drained and
it will, therefore, require less Ia
Dor and tile to put in the deeper
tile.
CAPACITY OF DRAINS.
| All the rainfall does not pass
directly into the drains. A por-
ton is evaporated at the surface,
a portion runs directly into the
stream, and a portion is absorbed
by the ground. The soil must
be thoroughly saturated before
any water enters the drains.
With the same temperature and
the same pressure it may be said
that the coarser the sand and
the smaller the amount of clay
the more rapid is the movement
of water through che ground.
The rate of movement is slower
near the surface than alta depth
of 10 feet. Likewise, the rate
of percolation is more rapid in
summer than in winter. It is
quite probable that about one
third of the amount of water alb
sorbed by the ground in Missis-
sippi is returned to the surface
as moisture By capillary attraction
and by roots Of vegetation.
With an annual rainfall of &c
inches about 100000 gallons OF
water to the acre enters the sol