The morning news. [volume] (Savannah, Ga.) 1887-1900, 1894-06-12
THE IMPURITY OF WATER.
Pure Water DoesNot Exist in Natur,

Pure Water Does Not Exist in Nature.
A Savannahian who has given consid-
cradle study to the subject OF water, re-
quests the MORNING News to publish the
following by DIR. Willis G. Tucker:
Pure water does not exist in nature 1t
is an ideal substance to which the purest
water that can be prepared by the chemist
only approximates From a chemical
standpoint every foreign substance which
water may contain is an impurity, but,
hygienically considered, water is called
impure only when it contains excessive
amounts of mineral matter in solution or
in suggestion; when it contains organic
matter of vegetable or animal origin. or
the products of the decomposition of such
matter in quantities exceeding certain
generally accepted but rather arbitrarily
assigned TO limits, or when il n to
contain living organisms ellie ed be
associated with or product { OF disc 3es
which water may comm unica
All filth in food or drink is alb
hored, but none the less, dlsolnction
must be made between that which, con-
tanning or accompanying specific disease
germs, may give rise TO spicifie diseases,
and that which is, while not unobjection-
able, yet apparently incapable of ma
terially affecting health.
The chemist is as yet unable to distin-
guish disease-producing from relatively
harmless impurities in water He can
recognize those constituents which indi-
cate organic pollution; demonstrate the
present existence of putrescent material,
or show that such material has previously
existed by the recognition of the products
of its decay, but he can by no means
assert with certainty that any given
water will necessarily give rise to dis
ease or will certainly prove TO be whole
some.
Waters containing putrescent organic
matter Of animal origin have been drunk
without harmful results. Such cases are
on record, and. on the other hand, waters
which analysis has shown to be of fair
chemical purity, have unquestionably
given rise to disease. Nevertheless the
chemical analysis of drinking waters
despite the limitations and imperfectionS
of our best processes, furnishes most val
liable information in no other way to be
obtained. There are unmlstakable
signs of pollution which analysis
may reveal, and such warnings should
not go UNDECIDED.
Impurities in water exist in suspension
or solution, and may be either inorganic
or organic. Suspended matter may fire.
quently be removed, wholly or partially,
by mere sedimeutation or by some simple
process offs liberation, but matter which is
held in solution must be destroyed or re-
moved in other ways. The boiling of
water may produce deposition of some
of its earthly salts, coagulation and pre-
cipitation of some of its organic matter,
and a destruction of its micro organism
including disease germs if present; and
while the method of publication is fire.
quently serviceable as a household meas
ure, 1t is not adapted to use upon a large
scale. BY distillation a S till further puri-
10, a
more costly process and can never come
into general use.
Within few days have examined a
sample of distilled water prepared and
sold in bottles for table use, in which,
while the free ammonia was high, the
albuminoid ammonia was very low chic
rine, nitrites and nitrates absent and
total solids almost nil. Such water is as
pure as can well be made on a CONNER
cial scale, but it is necessarily too expen-
sive to be commonly used. Aeration has
likewise been resorted to for the destruc-
tion by oxidation OF organic matter, and
is said TO have been employed more than
a century ago by Lind on the west coast
of Africa. Considerable improvement
has been effected in certain city supplies
by pumping air into the mains or reser-
voirs, or by discharging water in Jets or
fountains into basins so as freely to ex-
pose it to the air.
Where waters are shown to be de-
ficient in dissolved oxygen, especially in
the case of impounded waters in which
patches of green algR appear upon the
surface in warm weather, such treat
ment is often of the greatest value 1t is
an imitation of a natural process of puri-
fication, and the change effected is not TO
be regarded as purely chemical, being
brought about by bacterial organisms,
the nitrifying bacteria, which, under fav-
orable conditions and in presence of free
oxygen, convert nitrogenous organic mat
ter into harmless Inorganic forms.
The publication of polluted water by
direct chemical treatment has been
effected with more or less success In many
ways all practical methods involving the
separation of precipitated matter by sedi-
mentation or filtration after treatment of
the water. In other words, there is no
chemical agent which, by simple addi-
tion TO impure water, will render such
water pure and wholesome. BY chemical
treatment we maJ precipitate lime and
other earthly salts if present in undue
quantity coagulate and remove organic
matter and bacteria or promote the oM-
dation of such matter; and various pro-
cesses, accomplishing, more or less per-
fectly, these results, have, during recent
hoo lou Cd