The west Tennessee star. (Bolivar, Tenn.) 1888-1888, 1888-06-01
CAPnLARITY oE SOL.
a FrIneIpI. IN TIIl.ge whleh !. Attra'

CAEAELAhtl = OF SOiE.
A Principle In TEIlage which Is Attract /
ing Considerable Attention.
DR.. Z. Lewis Sturtevant, in using /
and explaining the term .'capillarity |
of the SOIL has formulated into doc |
trine what has been observed and des- |
ultorily taught through generations. |
The old writer's insist on fine tillage, a |
rendering of the soil into fine filth |
evenly graduated all through-and |
the famous exploits of Tull, and of
Smith, of Lois Weldon in producing
heavy crops continually without man.
ure on heavy clay soils, were results of
this intimately fine working of them.
A soil may be called capillary when SO
finely divided (yet without being
ground into powder-impalpable) as
to resemble the finest sand, the parti-
cles of which, as one may see in a heap
of broken roadstone. lie in close con-
tact, yet everywhere leaves spaces
communicating so as to allow water or
air free passage. When we take up a
handful of damp loan and press it it
falls apart again almost as readily as
the fine sand. yet not wholly, because
once quite near. by the attraction Of
cohesion. This same attraction also
allures the water, as is distinctly
seen when one end of a glass tube of
any caliber Gas piece of a broken
thermometer tube) is dipped vertically
in colored water; the water will be
seen rising quite far up the narrow in
terror and even drawn up against the
outer face of the glass as far as one
sided pull can take it. A lump of white
sugar with its base just barely touch
ing the same water will Immediately
draw it to the top, assembled through
the interstices. A dry clot of capillary
soil-loam-wi take up the liquid sim
ilarly. If the sugar is compacted into
candy, or the soil into a dense clayey
lump, this beautiful effect can not Oc-
cur. Too finely powdered loan, as
road dust for example, wetted into
dough and then dried, will be too COM
pact to admit of it. And if we crush
this dried cake or the cake of clay into
coarse fragments, the interstices will
be too wide for the power of attraction
to reach across and the water will fail
to climb up. It is like chimney
sweep of the clden time who could
mount up a fiue with back against one
side, and hands and knees against the
| other, but would fail in chimneys too
wide for such means of ascent
This principle underlies all soil-work
! ing, and should guide continually in the
management of heavy soils. It accounts
for the better success with wheat or
rye sown on cornstubbles without re-
| blowing. The sod that was turned
! down in the spring for corn renders
the soil, by the end of September, in
! the best condition of capillarity, but if
we pillow it again, tearing out the thick
corn roots, we can not restore that
same equally fine condition but leave
openings, especially among the corn
roots which both cut off the capillary
ascent of moisture and by becoming
filled with stagnant, damp air. form
chambers for the growth of molds that
are poisonous to the plant roots. The
supply of moisture to feeding roots Of
plants from below is superior to sur
face irrigation supply in at least three
respects: First, it is comparatively in.
expensive. Next, it feeds the roots as
well as supplies water to convey the
food; for the salts that dissolve into the
soil water at whatever depth, rise with
it to the surface, and it is only there that
they separate, as only the pure vapOr OF
water can take wing and rise among
the particles of air like as the solution
did through the particles of earth. In
dry autumnal weather we often see the
surface visibly coated with deposited
salts left behind in this way. Water
or irrigation may bring with it some
nutriment in solution, but it is very
often the case that it's excessive flow
carries this means of fertility beyond
the reach of the plants, if it does moi
even carry some of the soil away too
Much of the good effect of irrigation
on dry Western soils results from its
dissolving salts left at the surface and
; conveying them down again within the
reach of the absorbing roOt-points
This brings up third great merit o.
this capillary supply of the constantly
needed water-that its supply is con
slant as long as there is water below
and within reach of the capillary struc
ture of the soil, and also that its sup
ply is never in injurious excess.-W
g. Waring, ST., in NJ Y. Tribune.