Nashville union and American. [volume] (Nashville, Tenn.) 1868-1875, 1872-04-18

be the case from excess or over action 4
plaster performed any function at 81 to DC
assimlaied to that of saliva or Vegelaple
gastric juice.
Some say It is simply stimulant OF Fe-
eetation. This explanation viii not do' Pc
cause there is no doubt plaster perInaIeheiy
improyes the soil if the vegetation produced
by IL is not removed from the land. .O1Aers
attribute its power 10 its Possessnlg e.s
power Of supplying water ana ca a., =
to plants This explanation VIII nOS nu ~,
because of the fact that only very sHaii
qusntity of plaster will act when so"n up
on land in its ordinary cOndluon, ana II Is
only another form Of expressing the nrst
explanation of the action Of plaster, VIZ,
that It acts as a manure, whlch we nave
shown TO be untrue. Others say II owes It's
power to the fact Of its supplying sulphuric
acid TO plants, which is but modification
of other explanations which l have shown
to be untenable. The question still remains,
how does plaster act? l think can an
swer it in great part, if not TO the full salts
faction of the inquirer. 1t acts as con-
denser sf the ammonia of the atmosphere
and of the soil. Plaster of Paris is COM
posed of sulphuric acid and lime. A bushel
of this substance, if it acted as a manure,
would clearly exert but very small effect
upon an acre of land by its chemical action
upon plants, or by entering into combina-
ton in the growth of crops. BY observa-
ton, however. it is concluded that plaster Uf
Paris acts as a condenser of ammonia, which
is found everywhere in the atmosphere
and in all soils to a limited extent
that it holds this most subtle and
powerful manure in its grasp, fixes it and
gives it out to the growth of plants as they
require il, instead of allowing the ammonia
to pass away and remain unixed and I'M
adapted to plant growth. There are few
phenomena which seem to me to fully es-
tablish the fact that this is the true explana-
ton of the action of plaster: That only
certain amount viii act. Thus bushel to
the acre, sown upon a clover field, acts as
well as fifty bushels-showing that it does
not act as a manure, as stimulant, or
gastric juice, or In any other manner anu
Ogous to any of these agencies. Sow field
with plaster in clover, or any other grass,
leaving out breadth, or in plastering crop
of tobacco-as l have frequently seen it
done-leaving a few rows without the ap-
plication, and the result viii be that, while
the parts of the crop to which the plaster
is applied will be fourishing and green,
those on which no plaster is put will be yell
low and worthless, indeed greatly inferior
to what they would have been had no plas-
Ter been placed in the adjacent parts of the
field. How can this be explained except
upon the hypothesis that the plaster draws
from the atmosphere passing over it a part
of its fertilizing properties and retains it for
the use of the plants in proximity to it,
while those portions where there is no plas-
ter do not thus derive this greater share
from the atmosphere? Again, SOW upon
dunghill, steaming and giving off ammonia,
a quantity of plaster; enough-it will stop
the escape of the gas. Wait awhile, until
the plaster sown becomes saturated with
the gas, and it viii again begin to escape.
Put on plaster again, and it will stop; and
so on until all the ammonia is taken up
and fixed.
Take Peruvian guano, whose great fer
tilizing property is alALIonia, mix plaster
with it in proper quantity, and it will be-
come inodorous. And so of any other ami
NAL or vegetable manure which gives off
Great losses are sustained in stables, in
in all animal and vegetable ma
nures by the escape of ammonia, which
by far the richest part Of all
mamures. Plaster of Paris may be most
proitably employed in fixing this volatile
aud most valuable ingredient, to the great
profit of the farmer and the pubiic.-Nely
York Tribune.