Evening star. [volume] (Washington, D.C.) 1854-1972, 1883-09-22
HOMEMADE WATER FILTERS,
How 70 Procure Cheap and simple
Means Of Purifying Water.
From the New York Sun.

Means OF Purifying Water.
From the New York Sun.
To the Editor of the Sun-Sir: Having last
week pointed out in the Sun the impure char
acter of our water supply, 1 will now describe q
remedy which is within the reach Of every
householder
Pure water hardly exists in nature; It is in
sipid. and not adapted for drinking purposes
In speaking, therefore, of pure drinking water
shall use the term in a relative sense, indicat-
ing fitness. All l claim for water fit for drink
ing purposes is that it is free from everything
of ascertained or suspected power to induce i'll
health, or which is unpleasant to the senses aud
the Imagination.
All the eight water companies of London en-
ploy some system of filtration. The usual plan
is to build series of tunnels with bricks with
out mortar; these are covered with LAYER of
fine gravel two feet thick, then stratum of fine
gravel and coarse sand, and lastly layer of
two feet of fine sand The water is first pumped
into reservoir, and after time. for the subs-
dence of the cOarser impurities, the water flows
thronsh the litter beds. which are slightly
lower.
During the last summer / have been making
experiments with simple filtering materials. and
also talked the matter over with Prof Cassa-
mayer. chemist to Messrs. Havemeyer's sugar
refinery. Prof. Ca>samager having to filter
such difficult material as sugar. / considered
him an expert in all processes of filtration. and
L asked him to arrange what he considered the
cheapest and most simple form for ftering
water. AT his laboratory he showed me a
method which he had arranged, which is, per-
haps, the most simple that can be devised to
give fair results.
This simple filter is made as follows: Pro-
cure an ordinary wood pail and bore number
of holes the size of a fve-cent piece all over the
bottom. Next prepare fine muslin bag a
little larger than the bottom of the pail, and
about one inch in height. The bag is now filed
with clean well-WaShed sand and placed in the
pail. Water is next poured in. and the edges
OF the bag should be pressed against the sides
OF the pail. We put such filter to very severe
tests by mixing dry sienna color in gallon Of
water and. passing through, the color was so
fine as to be an impalpable powder, rendering
the water deep chocolate color. On pouring
this mixture on to the filter pad and collecting
the water, 1t was found free of all coloring mat
ter. This was a very satisfactory test for such
a simple appliance, and | cannot too strongly
recommend it in cases where more cOmpli-
Gated arrangement cannot be substituted. The
finest and cieanest sand is desirable. Sand pur-
chased at glass manufactures should be OBJ
tanned.
The above described filter at its best is but a
good stralner, and will arrest the suspended
particles. But in modern filter more perfect
work is required, and another effect produced,
In order that water containing Objectionable
matter in solution should be rendered tit for
drinking purposes. Many persons when they
see water quite clear seem to imagine that it
must be In a good state for drinking. They
should remember. however, that many sub
stances which entirely dissolve in water do not
diminish its clearness. Hence a clear bright
water may, despite its clearness, be charged
with poison or substances more or less in
furious to health; such, for instance, as soluble
animal matter.
To make perfect filter which should have
the double action of arrestng the finest sus-
pended matter and removing the matters held
In solution and the whole to cost but little and
capable of being made by any housewife, has
been the object Of my study for many months,
and. after many experiments and testing vari-
Gus substances in many combinations, l sug-
gest the following plan, which / find gives very
perfect results, and will cost couple OF dollars:
Purchase common galvanized iron pail,
which costs fifty cents. Take it to tin shop
and have hole cut in the center of the bottom
about the size of five-cent piece. and direct
them to solder around it piece Of tin about
three-fourths of an inch deep to form a spout
to direct the flow of water downward in a uni
form direction. Obtain about two quarts of
small stones at a store in Maiden lane where
material for roofing is sold; after good wash
ing place about two inches of these at bottom
of pail to form drain.
On this place partition of horse-hair cloth or
Canton flannel cut to size of pail. On this place
layer of animal charcoal sold at the who lesale
chemists in William street as bone black at about
10 cents pound. Select this about the size of
gunpOwder grains, and not in powder. This
layer should be three or four Inches. A second
PARTITION having been placed, add three inches
OF sand. as clean and as fine as possible. Those
within reach OF glass makers should purchase
the sand there. as it Is only with that quality of
sand that the best results can be obtained On
this place another partition, and add more fine
stones or shingle-say for two or three inches
This serves as weight to keep the upper partl-
ton in place.
Your filter is now complete, but not ready for
use. However careful you may have been in
washing the material, residue of dust will re-
main, and this has to be gradually washed
as possible through the filter during the first
day without using it. The next day it will be
ready for use, and II my directions have been
complied with, filtered water will always be at
command. not only freed from all suspended
substances, but from color due to matter held
In solution having been removed. found that
the yellowish color OF CrOton water, which is
very difficult to remove. was entirely absent in
water passed through my filter. To test this.
water must be filled up in large white porce-
lam basin. In this manner the color of CrOtOp
water is plainly visible in contrast with the
white china.
The filtering material, which is cheap enough.
and particularly the partitions, should also be re-
newed at intervals, the time depending on the
period of the year and the nature and amount
of the impurities.
For the benefit Of those DESTROYS OF filtering
water on large scale with sand filtering beds
would state that there should be one and
half yards of filtering area tor each 600 gallons
per day. For effective work the descent of the
water should not exceed six inches per hour.
The terms ''sef-cleansing," applied to some fill
tiers on the market, may be correct in limited
sense, but no reliance should be placed on such
hlters, and none used which cannot be readily
taken apart and thoroughly ceansed
] have Otter noticed wood charcoal used in
filters. The best authorities, however claim
that this material when powdered, acts merely
In a mechanical manner as a strainer and that
charcoal obtained from animal matter alone an
pears to possess the power of removing matters
held in solution in water -td1St !
There is one fltering lnatetial which is little
known in this country which has all tho prom
critics of animal charcoal, and is said to give
higher results This is magnetic carbide dis
covered by Spencer many years ago, and con-
sists of rrotOxide Of iron in chemical combina-
tion with carbon. 1t is considered that the puri-
Tying effect is produced by its power of attract
Ing oxygen to its surface without the latter
being acted on, the oxygen thus attracted being
changed to ozone, by which the organic matter
in the water is consumed
- There can>be no doubt of the value Of this