Evening star. [volume] (Washington, D.C.) 1854-1972, 1899-01-14

towns and for a large agricultural popu-
lation along it's banks. With increasing
density of population and with the actual
and prospective sewering of the largest
cities there will be annual increase in
the pollution of the river with sewage.
80. Typhoid fever is prevalent in the
cities and towns along the banks of the
Potomac above Washington. With increas-
ing density of population there is every
year an increase in the number of cases
of this disease. and a resulting increase in
the contamination of our drinking water
with Its specific cause. With the increase
OF typhoid fever above us there will be an
increase here. This is proved by the eX-
perience of Lowell and Lawrence Massa-
chusetts. With the increase of typhoid
fever in Lowell there was invariably d
corresponding aggravat1on in Lawrence,
which receives its water from the Merri-
mac river, about ten miles lower down.
3. The impclcy and absurdity of using
the same river as a sewer and as a source
of the supply of drinking water is appar-
ent; but in the nature of things this is
sometimes unavoidable. There are two
ways of leSsen1ng the evil: To prevent the
contamination of the river with sewage or
TO get rid OF such contamination before the
water is used With Potomac water the
first of these modes of prevention is i'm
possible now, and will be so for long time
to come. The only course left is to purify
the polluted water before receiving it into
our city.
failure; even the water flowing over Mag
ara Falls is not made pure by its great
agitation Prof. Leeds, and the effect of
sunlight in destroying bacteria does not
extend ten inches below the surface Of
hoWlng or still water. Buchner)
-. To get rid of organic matter and dis
eaSe-producing bacteria filtration is the on
ly successful method. Mechanical or rapid
nItraton does not get rid of bacteria; slow
intermittent or sand filtration alone does
h.alS of
Lawrence, Mass Were put in use seventy
five per cent of the contained bacteria
came through the filter. in the next three
days thirty per cent. later four Der cent
and in another week two per cent only es-
capped arrest in transit. The filter removed
from the water '9S.3 per cent of all the
bacteria in the water applied to it With
the removal of the bacteria their food ma
terial is also destroyed, so that their num-
Der decreases after leaving the filter and
flowing through the pipes. At the tap in
the city of Lawrence the number of bac-
terra is nine-tenths of one per cent of the
original number in the unfiltered water
More than ninety-nine per cent of all the
bacteria OF the river water are thus re-
moved.
6. with the reduction of the number of
bacteria typhoid fever lessons and NAV al
most wholly be made to disappear During
eight months before the filter beds of Law
renee We're begun there We're forty-three
deaths in Lawrence from typhoid fever In
the year after the filter was made there were
seventeen deaths, difference of twenty
six. During the first eight months use of
the filter the death rate from typhoid fever
was reduced to 40 per cent OF former NOR
tality, reduction of nearly One-half. In
stead of forty-three deaths the number fell
to twelve and then to seven, or about one
fifth of the number of deaths before filtered
water was used, and about one-half of the
average number of deaths from typhoid
fever in the other cities of Massachusetts
Z. THE practicability of protecting this
community against an infected drinking
water is not only demonstrated by the ex-
perience of Lawrence, but of other cities in
this country and Europe. The following
figures give the death rate from typhoid
fever in 100000 population before and after
Uttered water was used in five cities: