Evening star. [volume] (Washington, D.C.) 1854-1972, 1885-09-19

experiments Made ~ MI. Sims
new the Water Can - ClarlasA with
Little Trouble.

Mr. g. @. c. simms, the pharmacist, has been
testing the purity of the Potomac water.
ana the relative merits OF chloride Of iron and
sulphate OF alum as a purifier. He has MADE a
seres OF niteen experiments. The first thing
SHOWN is that the Potomac water contains con-
SIDERABLE foreign matter in solution, which. he
.ninks must necessarily be detrimental to
neaith. Boeing the water does little or nothing
towards purifying it, and even distilling IL fails
70 remove all the impure matter. Filterine
through charcoal and sand filter 10 quite sat
hs a but to secure perfectly pure water he
drops OF solution OF chloride Of iron or three or
-FOUR grains OF snlphate of alum. He finds the
ment was with 1--WE pints of water mixed with
Two drops OF solution of chloride OF iron. Amer
stSn9lng an hour or two there appeared about
precipitste, evidently consisting Of hydrated
oxide OF iron, and organic matter which was
nso IN, IN solution and suspended in the water be.
tSenty-oaf hours Was perfectly clear and pure s
tinous and heavy. Some Of the same
water altered through absorbent cotton
IN the mouth OF q funnel an hour or two
after adding the iron became as limpid and
pure as the best spring water and was equally
as palatable. Potomac water filtered through
chloride of iron added Afterwards, showed .
slight precipitate OF oxide of iron. This latter
experiment shows that by passing the water
through a sand and charcoal filterer IL "A de-
prived OF most OF the impurities which are
thrown out of solution by the iron. The water
filtered after the chloride was added remained
perfectly clear. II was found by Experiment
that two drops Of chloride of iron was SUFFICIENT
to purify five pints OF Potomac water as IL was
on the 14th OF September. Iron added TO dis
titled water gave a slight color to the water but
there was no gelatinous precipitate. A sample
Of Potomac water which had been boiled did
not clear itself in several days, although IL was
filtered through cotton like the other samples,
indicating that the mere boiling of water
will not purify 1t. Chloride of iron
added to this sample purified IT
very quickly. Sulphate Of alum had
similar effect to that of the iron, on all the
water 1t was tried upon, and was found in every
way equal TO the iron as . purifier. Water
purified with alum and then filtered was found
to be as clear and palatable as the best spring
water. In this experiment grains of alum
were used to a gallon of water. Further expert
ments showed that about Ga grains ought to be
used. The alum added TO distilled water found
impurities that the iron had failed TO notice,
and drove them out q precipitate. The
experiments show that the Potomac water may
be rendered perfectly pure without any very
great trouble. Ten cents worth Of chloride OF
iron or sulphate Of alum would purify hogs
head Of water. 1.-two or three drops Of the iron
or Big grains of the alum were put in q gallon OF
water and allowed to stand over night, the
water poured off from the sediment would be
II, after being so treated, ltering water cooler