The Fairfield herald. [volume] (Winnsboro, S.C.) 1849-1876, 1867-09-18
Filteling and Other Purifying Agents.


Tho London Lancet in addition to
its ordinary duties of journalism, vol
untocrs investigations on large scale,
for public benefit, into sanitary mat
ters, thus giving to itself wide
range, and we may venture to say
performing higher services than when
it is The record of medical and surgi-
cal proceedings, valuable as this is. 1t
was asanitary commission of its own,
which has published two reports on
the interesting subject designated by
tho heading Of this article. In tho
first report it stated the following ill
tors had been examined: First, the
syphon filter of tho London Water~
Purifying Company, in which the ill
tcring and purifying material is ami
NAL charcoal: second, the moulded
carbon filter third, the sllicatcd car
bon filter, and fourth, the magnetic
carbide filter. OF these fou" the COM
mission gives decided preference for
tho filter last named, the composition
and general merits Of which We dcs-
cribcd in the Ledger nearly n year
ago. The filtcring substance, some of
our readers may remember, is q black
oxide of iron, or red ochrc, with saw
dust. The filter for domestic use, we
now state, consists Of a stoncwaro jar,
divided into thrco chambcrs--thc
lower for storing tho fltcring water;
tho middle for holding the fltoring
material, and the top for receiving the
water to be filtered. The lower par
tition, on which tho fltcring substan-
ces rest is provided with hole, pro-
toctcd by y patented invention for
keeping these substances from getting
through. On this partition is placed
thin layer of sand, and over this q
deep layer Of magctio carbide, in
coarse powder. The upper partition
is perforated with holes, tho upper
surface of the perforated part being
covered with stonewaro dome, usual
y left open on top, but intended to be
loosely stopped, when tic water to be
filtered contains much suspended mat
tcrs, and thus to prevent clogging of
the filtcring bed. We arc assured by
the Lancet Sanitary Commission that
This filter has not. only tho property
of removing nearly all dissolved
organic matter from water, but it
retains tho power of doing so for an
unlimited period, therefore requiring
no renewal Of material. This opinion
is repeated by tho commission in its
second report, in unqualified terms.
Fed with water from a'notcd Thames
water works, stored in a house cistcrn,
it gives rapid supply Of water, of
excellent quality, bright and colorlcss,
free from odor, even when warmed or
stored up for days, and containing
only an exceedingly minute quantity
of organic matter. 1t has not been
found to communicate any substance
to the water.
The silicatcd carbon filter consists
of mass Of "silicatcd carbon" made
OF coke, ground to powder and incor.
poratcd with pitch by the aid OF heat.
1t is then formed into cakes by pres.
sure, and subjected to high tompcra
turc so as to carbonizc tho pitch, tho
tiltoring mass is arranged in the filter
by placing a layer Of animal charcoal,
mixed with PARTICLES of silcatcd car
bon, between two prepared cakes
ccmcntod into the vessel. The water
yielded by this filter does not pass in
desirable quantity, and it is not so
free from organic matter as that yield
cd by tho filter previously mentioned,
nor is its action permanent. The
simple. moulded carbon filter is analo-
gous in its composition to the ono last
mentioned it docs not find favor with
tho commission. Tho same may be
said of the animal charcoal filter Of
the London company. Tho cistcrn
litter acts much the same as tho last
named.