The herald and mail. [volume] (Columbia, Tenn.) 1873-188?, 1875-10-01
Cisterns And Soft Water.

The ordinary use of a cistern is to sup
ply soft water for washing purposes. In
many localities in the country, especially
where it is difficult to dig wells, and hard
to obtain materials to wall them up, els
terms are often used for storing water for
drinking. Rain water stored in cisterns
is not very desirable for drinking. Apart
from the consideration that it is liable to
be very warm in summer, when it most
required, it almost always contains vege-
table and animal impurities taken up
while falling through the air. These i'm
purities are often so large in amount that
they produce fermentation after the water
has stood some days during warm weather.
After rain water has undergone this
process of publication it is good to drink;
but it is not easy to obtain purified water
from a cistern where water enters every
time it rains, and from which it is being
taken out every few hours for domestic pur-
poses. 1t is practical to make filters and to
attach them to cisterns so that the water
may pass through them and be purified
for drinking purposes There is, how
ever, considerable trouble and expense
attending this course, and the filters, how
ever constructed, are in need of constant
overhauling, as they become filled up by
the impurities that lodge in them.
There is such a thing as having water
too pure for drinking purposes. 1t is a
well-known fact that distilled water is not
wholesome to drink. 1t is not unhealthy
because it does not contain any vegetable
or mineral substances, but for the reason
that it contains no mineral substances,
and, unless it has stood some time, no air
or carbOnic acid. The presence of these
gases appears to be necessary to digestion
and health. The presence of some min
eral matter, especially lime in drinking
water, is of the first importance. The
best water for drinking purposes always
contains lime or other mineral matter.
The presence of magnesia in water causes
it to be ''hard." BY "hard" water is
meant one that will decompose common
soap, and will form soap that is insoluble.
Lime will form hard white soap that
will separate in the form of flakes. The
hardest waters-that is, those that will
decompOse soap the most readily-are
found in springs and deep wells, especially
in limestone regions. Most of the streams
and lakes in the west contain water that
is only slightly 'hard." The water pro-
vided for the use of this city is somewhat
''hard," though it is generally used for
washing purposes. All water which de-
scends from the clouds is soft, but it is
liable to become "hard" as soon as it
comes in contact with the soil, or with
rocks. Water which contains no carbOnic
acid does not dissolve limestone readily,
but all water will take up this gas, when
it will become "hard." 1t is desirable to
store water in some reservoir that con-
tains no lime if we wish to keep it soft.
Practically we can only keep it soft in
vessels made of wood, glass or metal. As
to metal vessels, they are too expensive,
while iron will be dissolved in water and
will stain garments.
Most housewives are aware of the fact
that rainwater which has stood for some
time i'll a cement cistern has become
"hard." At first it washes beautifully,
removing the dirt from clothes or the skin
with the use Of a very small amOut of
soap. After a while more soap is re-
quired. At the end of some weeks it is
about as difficult to wash with it as with
that taken from a spring or well. First
it was entirely soft, then moderately
"hard," and finally it became very
"hard.' To express it in other words, it
contained at first no lime, then little
lime, and finally a good deal of lime.
The reason for this change may be
given as follows: The cement of which
the walls of the cistern are made is
largely composed of lime. When first
applied it is in the form of quicklime,
but it is soon changes to carbonate of
lime. Pure water Will easily dissolve
the last named substance. Water falling
through the air takes up carbonic acid.
Cistern ordinarily contain leaves and
other vegetable matter. These decay
and give off carbonic acid, which mikes
with the water. The water charged
with carbonic acid will readily dissolve
the carbonate of lime, when it will be-
come "hard" It is now no better than
well or spring water to wash with.
The above shows why a cistern should
be made of wood or Of some substance
that does not contain lime. The diff
Guilty with a wood cisteTn consist in the |
liability to rot out. This may be pre-
vented in a great measure by setting the |
cement, that is, by having a layer |
Of cement mortar below around the wood |
work. If a cistern is made of cypress
wood it will last during an ordinary life
time. This wood grows abundantly in
Ill the southern states, and in the lower /
portions Of Indiana and Illinois. 1t con-
aims a good deal of resin, which prevents
Is Iotting. It's value for making cisterns
las never been appreciated.