Mineral Point tribune. (Mineral Point, Wis.) 1869-1938, 1876-04-19
The AbsOrptive Power or Soil,

IT is an important discovery OF recent
date, that soils have the power of separ.
ating not only ammonia, but other bases
also, from their solutions, and of holding
them with great tenGcity after their al.
sorption. Thus 1OO, grains of clay soil,
taken from the plastic clay formation of
England, absorbed ,05O grains of potash
from a solution of caustic potash contain.
ing one per cent. of the alkali. 1t is inter.
esting to observe that the liquid was not.
in this case, filtered through the soil, but
the cold solution was merely left in con.
tact with it for twelve hours.
1t has been further shown that soils
have the ability to separate the alkaline
bases from the acids with which they are
combined. When saline solutions are
slowly filtered through soils five or six
inches deep, the liquids which passed
through were deprived of their alkaline
bases, as potash, soda, ammonia and
magnesia, and only the acids were to be
found in combination with some other
bsse Thus, when muriate of ammonia
was filtered through the soil the am
nOnia was removed, and correspond.
ing quantity Of lime, in combination with
murlatic acid, was found in the filtered
liquid. In the same way sulphate Of
potash was deprived Of its base, and the
liquid collected gave sulphate of lime
Those soils which have the greatest
amount of capillary porosity will con-
dense the greatest amount of manurial
substances on their internal surfaces. will
retain them longest against the adverse
solvent action of water, and will give
them out most readily to the rootlets of
the growing plant.
A mass of adhesive clay will absorb but
a very slight amount Of available manure;
but If this same mass is rendered frable,
by mechanical processes, its power of alb
sorption is amazingly increased. In view
of what has been stated, it is very clear
that one way In which blowing increases
the fertility of land is by increasing its
porosity by pulverization.
Again, many manurial substances exist
in the soil, which, being insoluble, exer.
else no action on the growth Of plants,
and contribute nothing to their nutrition;
but by the slow, though regular action OF
the irosts and the rain, the air and the
sunshine, insolrble and refractory CON-
pounds are reduced to "A soluble state, and
are appropriated and held on deposit by
the soil to the credit of the next cultivated
crop. This explains the well known fact
that SOILS which have been cropped to
the very verge of barrenness, will recover
their fertility if allowed to remain long
enough under the action of climatic in
tluences flo saturate the soil with the
necessary plant food, which they have un-
locked from their chemical combinations,
and given to the soil in proper physical
condition. These changes are brought
about more rapidly when certain mechan-
ical changes OF condition are wrought up
on the soil
Carbonic acid is one of the most active
of the agents employed in bringing the
insolublc organic matter in the, soil into
hat physical condition in which it be-
comes available rs plant-food In order
that this acid may be formed, it is essen
tia that the carbonaceous matter in the
soil should be brought into direct contact
with the atmosphere, from which they
procure the oxygen necessary to convert
them into carbonic acid. So Tonga as stag
nant water remains in the soil, or so long
as the soil is in a dense or very compact
condition, it is impossible for the carbon
to be converted into id-JoarAal Of
Chemistry.