Iowa voter. [volume] (Knoxville, Iowa) 1867-1874, 1870-05-26
FARM AND HOUSEHOLD
Movements II watsrsia the SoiI.a

oil, the oil, BY capillary attraction, gradual
~ permeates its whole length, sbat which is
above as well az that below the surface of
the liqnid When the lamp IL set burn
ing, the oil ct the fame is consumed, and
as each particle disappears. its place is
supplied by q new one, until the lamp is
empty or the fame is extinguished f7i'' y
Something quite analogous occurs in
the soil, by which the plant is fed. The
soil ID at once lamp and wick, and the
water Of the coil TepYesents the Jill. Let
evaporation Of water from the surface of
the soil or Of the plant take the place Of
the combustion Of oil from q wick, and
the matter stands thls.*Let us suppose
dew or rain TO have, saturated the ground
with moisture for some depth. On recur-
renee OF q dry atmosphere with sdnshine
and wind, the surface of the soil rapidly
dries; but as each particle of water dries
Thy eyapc.sti0nj into the atmosphere. its
place is supplied (by capillarity} from the
stores below. The ascending water brings
along with it the soluble matter Of the
soil, and thus the roots of plants are eitu-
ated in 4 stream of their appropriate food.
The movement proceeds in this way 20
long ~ the surface il drier than the deep
er coil. When, by rain or otherwise, the
surface is saturated, it is like letting thin
stream Of oil run upon ii the apex Of a
lamp wick -n0 more evaporation into the
air can occur, and consequently there is
no longer any sscent Of water; on the
contrary, the water, by its own weight,
penetrates the soil. and IL the underlying
ground be not saturated ' it'll moisture, as
can happen where the subterranean foun.
tains yield meagre supply, then capillar.
ity viii aid gravity in its downward dis
II is certain that . portion Of the mine
raj matters, and perhaps also some or
ganic bodies which feed the plant, are
more or less freely dissolved in the water
of the soil. So long IS evaporation goes
on from the surface, 80 long there is con-
slant upward flow Of these matters Those
portions which do, not enter vegetation
accumulate on or near the surface OF the
ground when d rain falls, they are washed
down again to certain depth, and thus
are kept constantly changing their place
with the water, which is the vehicle of
their distribution. In regions where rain
falls periodically or not at all, this upward
flow of the soil water often causes an &C
cumulation of sails on the surface of the
ground. Thus in Bengal many soils
which in the wet season produce the
most luxuriant crops, during the rAinless
portions of the year become covered with
white crusts of saltpeter. The beds of
nitrate of soda that are found In Peru,
and the carbonate of soda, and other salts
which incrust the deserts of Utah, and
often fill the air with alkaline dust, have
accumulated in the same manner SO in
tour western caves, the earth sheltered
| from rains Is saturated with salt-epsom
salts, Glauber's salts, and saltpeter, or
mixtures Of these Often the rich soils
of gardens is slightly incrusted in this
manner in our summer weather; but the
saline matters are carried into the soil
with the next rain. .{fI8
1t is easy to Zee how, in good soil,
capillarity thus acts in keeping the roots
} of plants constantly immersed in a stream
of water or, moisture that is now ascend
ing, now descending, but never at rest,
and how the food Of the plant is thus
made to circulate around the organs fitted
for absorbing it, 500 ala ~, .s,a1
The same causes that maintain this per
petual supply of wster and food to the
plant are also eff1caciOus in constantly pre-.
pairing new supplies of food. AS before
explained, the materials of the soil are al.
ways undergoing decomposition, whereby
the silica, lime, phosphoric acid, potash,
ETC., of the iDsoluble fragments Of rock,
become soluble in water and accessible to
the plant. Water charged with carbonic
acid and oxygen is the chiefagent in these
chemical chsnges The more extensive
and rapid circulation of water in the soil,
the more matters will be rendered soluble
In a given time, and other things being
equal the less will the soil be dependent
on the manures TO keep up its fertility
HoW Crops Feed. " 7t.'s'