The Milan exchange. (Milan, Gibson County, Tenn.) 1874-1978, 1878-09-19
FARM TOPICS.

HE USE OF PLASTER.-There is
scarcely farmer who does not know
how useful is dressing of plaster or
gypsum to land-beariDg clover. But
while this is thus, and although this is
the best possible season to use plaster
upon the young clover, yet it is very
rare to see any use made of it at this
time. Perhaps plaster has been hardly
used by its friends more than by those
who have no faith in it. Many things
are said in its favor which are untrue,
and what is worse, are unreasonable.
We recently read an otherwise excel
lent article upon the use of plaster,
which contained the statement that one
of the benefits derived from it was that
it attracted moisture from the atmos-
phere, and so kept the ground from dry
lug up. Now that statement is untrue
and unfounded, as any one may know
who understands the character of this
mineral. And so with many other
wrong statements about it, and wrong
directions for using it, based upon the
erroneous statements.
Plaster is a sulphate of lime in COM
bination with water, consisting of 1924
per cent. of lime, 464 per cent. of sui
phuric acid, and 81 per cent of water,
not absorbed, but combined as water of
crystallization. When raw gypsum is
burned or heated to about 100 deg.
above the boiling point, this water is
driven off as steam, the massive gyp-
sum falls apart into powder, the parti-
cles being forced asunder by the expan
sive steam; and, If the gypsum is
ground into powder, this boils and bub-
bles by the escape of the steam from the
contained water. After the water has
been thus driven off the gypsum be-
comes the ordinary plaster-Of-Paris, SO
called because it was first used as plas-
ter at that city. This is the material
used for hard-inishing walls, for
cornices of rooms, and cements of vari-
Gus kinds, and is well known from its
property of setting or becoming hard
when mixed with water. This property
of setting is derived simply from its re-
combination with water, from which it
was separated by heating at the first,
and its return to q solid condition. Now,
it is evident that while in a raw state
and already holding in combination all
the water possible, it can not absorb
any more; nor can tpart with its water
to the soil, because to do this it would
require heat of 500 deg, or much more
than that of boiling water, which is but
2l2 deg.
The simple truth of the matter is that
sulphate of lime, in its combined state,
is constituent of MANY plants, but of
clover especially; that lime and sulphur
ic acid, separately, are found in nearly
all, if not all, plants in some proper
ton; that gypsum, being a sulphate of
lime, and containing both lime and sui
pluric acid, is really q needed food for
vegetation, but especially so for clover,
for which it is a most necessary nutri-
ment. AS plant thrives best when it
is well supplied with proper food at the
right time, and as the right time is
when it is young and needs to grow Wig
orously, it follows shat just now liber-
al dressing of gypsum upon the young
clover will be found extremely bene-
fetal. That it acts with greater effect
in rainy weather is due to the fact that
it is soluble only in 400 times its bulk of
water, and that considerable rain is,
therefore, needed to make it ready for
absorption by the roots of the clover.
Its rapid action is seen by the almost
immediate deepening of the color of the
vegetation and the more apparent vigor
of its growth.
The quantity usually applied is 100
pounds per acre; but this is not suffi-
cient for full effect. 1t is cheap, and
full dose can well be afforded. At $40
per ton, 500 pounds per acre will be a
very cheap dressing. If it is ground
very fine the effect is produced more
rapidly than when it is in coarse pow
der, and it is best to use it in the finest
state of division. There are other uses
on the farm for gypsum. As a purifier
of stables, cesspools, poultry-hOuseS, or
other foul places it is very effective. We
have heard from those in whose opinion
we had confidence that it would not act
as deOdorizer when in dry state and
not until it had entered into solution.
This opinion, however, is not founded
upon fact. 1t operates as a deodorizer
by absorbing ammonia and the pungent
ammoniacal vapors which are produced
by decomposing organic substances. 1t
is capable of absorbing ammonia when
dry, for it will quickly purify a foul
poultry-house when scattered freely
about it, although the place and every
thing about it is perfectly dry. Besides,
if small quantity of dry powdered
gypsum be placed in glass tube, and a
current of ammonia, which is really q
gas, be passed through it from bottle
of ordinary ammonia water, it will be
found that the gas will be absorbed
in greater part, and its pun
gency be greatly diminished.
However, in practice, it will be
found that to scatter it freely about
stables, cow-sheds, yards, pig-pens,
cesspools, manure heaps, slop-sinks,
and all such disagreeably smelling
places, will quickly stop the odors and
completely neutralize them. The effect
is to unite the ammonia and the sui
phuric acid of the plaster, producing an
inodorous sulphate of ammonia, and to
leave the lime free; this very soon unit
ing with carbonic acid, which is abun
dant in all decaying substances, and
forming carbonate of lime. Gypsum is
the more valuable because it helps US to
grow large crops of clover, which, in
its growth, draws from the soil from q
considerable depth many of the most
needed substances for the growth OF
crops, and leaves them upon or near
the surface. The deep-feeding roots Of
clover bring up from several feet below