The Anderson intelligencer. [volume] (Anderson Court House, S.C.) 1860-1914, 1884-10-16
DROUGHT.
by II. Puryear, LII. d., Professor:of Chem
istry I'm Richmond College.


rEEr
Who feels like work, who can work.
under this dead September heat? viii
scientists explain why the came temper.
ature in June and September Is 80 much
more iptolerable In the latter case? Ia
the September heat unpolariEed heat Z?
Certain it IL that temperature which
we can easily bear In June Is grievomsly
distressing In September. Who will rise
to explaihf
One would think that, having been
accustomed to the heat of Summer, we
could better bear high temperature in
September than In early Summer, but II
Ia not 80.
But we are contending now not with
heat only, but with q severe and protrac.
ted drought. Tho drought now upon us
ia severe because tho atmosphere is ex.
tremely arid. Droughts occurring at the
same seasons in different years, aud with
the temperature of the atmosphere the
same, may be very unequally disastrous.
In one case the blades Of corn may twist
and wilt Ia ten days after the drought
sets in; in another case, not for three
weeks or more-perhaps not ut all.
Why? We must remember that seventy.
FIVE per cent, and frequently more, of
living vegetation is water, and that this
water is just as mnoh part of the plant
as the condensed solids that constitute
the vegetable skeleton. Now, water 10
always passing, by evaporation, from tha
leaves Of plants, aud the rate of ovapo.
ration depends chiefly upon the hygrom-
etric condition of the atmosphere,
When the atmosphere is very dry, II
sucks up moisture from plants rapidly;
when the atmosphere is humid, evapora.
tion takes place slowly, and Is arrested
altogether when the atmosphere is satu.
rated with aqueous vapor. 1t is obvious
then that evaporation may take place
very rapidly during drought, making
the drought disastrous; or very slowly,
so making tho drought comparatively
harmless. For more particular illustra.
tion, let us Say that 1t has not rained for
two weeks, and that the atmosphere 10
very dry. In such case plants lose
water by evaporation rapidly, and i'm
mediate and serious damage eneuea. r.
But II, whilo no rain falls, the atmos.
phere all the time is humid, evaporation
will take place slowly and plants will
suffer but little, If at oil. The loss of
water by evaporation from the leaves,
when the atmosphere is humid, Ia 60
small that it ID supplied, or nearly sup.
piled, by tho water constantly introduced
by the roots, aud hence the drought may
be much protracted before infliotipg seri.
GUS detriment on growing vegetation. A
drought then of given length and with!
Q certain temperature may be disastrous.
In another year and at the Same season,
another drought equally long, and &C.
companied by the same temperature,
may occur and do but little damage. In
the former case the atmosphere is dry,
and evaporation Ia rapid; in the latter
the atmosphere 10 humid and evapora.
ton slow.
Have we any remedy against droughtsP
To no uncomfortable extent we have,
and that remedy is deep plowipg.
I. Deeply plowed lands receive, when
rains are abundant, into their substance
all or nearly oil the water that falls;
none or little rune of from the surface.
Such lands have therefore larger store.
house of water, from which plants may
draw their supplies-crops will stand q
drought better for this reason. But the
farther the water sinks into the substance
of the soil, the smaller is tho amount
which The hossua az sst,r1nlsr Will s7ap.
crate. Twelve inches beneath the sur.
face, the coil 10 many degrees cooler in
Summer than the surface, and hence II
the soil be once saturated TO that depth.
much less water Is dissipated and lost by
solar heat. Deeply plowed lands, there.
fore, not only receive into their substance
more water when rains are copious, but
hold this water with greater grip and
tenacity. ~
2. A deeply pulverized soil Is permea.
bic by the atmosphere, and the atmoB.
phere, how dry soeyer, always contains
some aqueous Vapor. In perfectly dry
atmosphere our bodies would shriSel in O
very few hours into mummies; all plants
would wilt and die In day. When the
can descend deeply into the:
soil, the cool soil deprives the aqueous
vapor Of heat, and 90 converts into water
and deposits 1T just where it is most
needed, about the rootleta Of plants. In
other words, in deeply plowed lands dew
is Le!ag asiF.ocss!!!.ssda Il; siryinS quantities
all the time about tho roots. Here 10
another reason why crops stand droughts
better in deeply plowedlauda.
8. Water ia always rising from below
by the capillarity Of the coil, but It rises
slowly through hard and compact aoii
with ease through deeply pulverized
soil. Hence the moro deeply the soil IL
plowed, the larger will bethe amount of
water drawn up from below by capillary
Can philosophy draw comfort from o
drought? When the fields are dry and
parched, when the water courses are fall,
ing, and our domestic animals are
pinched both for food and water, and the
hopes are blnsted.-are there no
compensatiDg advantages7 We think
there are, and we give them for the com.
fort Of the despairing and dependent.
During q droIEht tho soil is collecting
its forces and recnperating Its energies
for better work in the ensning eeasoH.
Let us see. 81 .ft 2 is's
IF from q damp cellar We take q cube
Of cut sugar and touch q point. of water,
the water will strike slowly through the
mass Of sugar. But II We take q cube of
cut sugar. made perfectly dry BY expo,
sure to the hot sun, and touch It to
water the water In a moment flashes
through the lump. The difference with:
which the two Jumps receive water , is
striking and obvious. The dry lump ia
q tenth Of the time vii. .sceiye ten times
as much water into it's substance as the
moist lump. til just 80 with the earth
tho dry lump OF sugar repreaentsi the
earth in drought the drier the Boii, the
stronger Is the tendency of water to rise
from below. toi the surface, where iE is
evaporhted. But water never comes To-
tho surface simply: as water; Il must
come charged with all the soluble mate.
rial, which 1t has encountered in It's