Evening star. [volume] (Washington, D.C.) 1854-1972, 1901-01-05

spreading typhoid fever, and he thought
the conclusions Of the Medical Society OF
the District were not justified by merely
recftfng the results In q few places where
there are mechanical filters and attributing
all the typhoid fever to the water. He said
that strong point In regard to mechanical
nItration as a disease preventative was
that the filter beds of such filters could be
quickly and easily sterilized by being boiled
by the aid of steam, which Is conveyed to
the filters by pipes arranged for the pur-
pose. Consequently. II there should be
suspicion of a typhoid fever germ or germs
having gotten into a mechanical filter bed,
1t could be sterilixed in a very short time.
AS an instance of the way that statistics
tistics gathered by the state board of health
OF Massachusetts. covering the death rate
Tor periods of five years from 1871 to 1899.
inclusive. These statistics show that from
1871 TO 1870 the death rate per 10000 of
population was o. and that for~four years
from 1895 to 1899, after slow sand filter was
introduced at Lawrence and was in opera
ton, the death rate due to typhoid fever
was 20 per 10000. showing a reduction of
% per cent. 1t is also shown, he said. in
the same report that the average death
rate Que to typhoid fever in four large
Massachusetts cities which do not have
filters during the twenty years above re-
ferred to was 81 per 10000 of population,
ana that the death rate in these same cities
curing the four years from 1896 to 1899 was
Fl per 10000. BY these figures it can be
seen that there was reduction of Il per
cent in the typhoid fever death rate with
out the aid OF filtration, reduction of only
per cent less than at Lawrence. and these
ngures also show that the number of
deaths per 10000 during the four years
was about II per cent less than at Law
renee, where filtered water was used.
Criticism of Medical Society.
The claim of the witness that the Medi-
cal Society of the District had presented
statistics from only a few of the cities
that have had the mechanical system of fill
tration Installed was referred to by DR..
Woodward, who asked the witness is he had
statistics Of any ohter cities than those re-
ferred to by the Medical Society," and he re-
Piled that he did not
Mr. Weston was asked by Mr. Moore
why it was that Pittsburg, Pa, had decided
to introduce the slow sand instead of the
mechanical filters. but he preferred to have
MI. Hazen, who designed the plant to be
erected at Pittsburg. reply to the question.
MIR Hazen said the slow sand filter was
selected because 1t was expected that bet
ter meteorological results would result from
it. and as the sewage in the water lat Pitts
burg is increasing they considered the bac-
THEOLOGICAL feature the chief one. At the
same time, 1t was thought a sufficiently
clear water could be secured by the slow
sand method.
Mr.. John w. Hill of Cincinnati. now con-
sulting and principal engineer for the con-
struction CT filter plant at Philadelphia.
SstiO tIie EidllS uIueT way lUF llldl CITY
contemplate a slow sand filter there. He
had formerly installed slow sand filter at
Cincinnati. He was asked why he preferred
the slow sand filtration system. He replied
that he preferred to secure the publication
of water by filtering it through sand alone
instead OF through sand with the addition
of chemical. He had first investigated
this question many years ago. when there
was prevalence of certain form of stom-
ach trouble which peculiar to the
guests in hotel in Cincinnati With others
he investigated this subject and discovered
that there was alum in the filtered water
of the hotel. which was supplied with me-
chanical filter in which alum was used as
ont