National Republican., 1885-06-06
rnn rupL1c oN OLE wArEn.


IAN hAaNtthN AAaA AsN-AfASAN 9AhRAas
EDITOR NATIONAL REPUBLICAN, !
have been very much interested in the
results Of the various analyses of the Po-
tomao water as published in THE REPuB-
L1CAH, but havo as yet seen mono that
explained what the pollution ia and how
20 destroy IL, though the source OF tho
pollution has undoubtedly been found.
Many inquiries having boon made as
to tho cause of the fishy odor of tho
water, / mado an observation Of 10 Juno
in the following manner: Tying n small
pioco of stout fine muslin to tho spigot,
strained twenty gallons Of water at tho
rate of four gallons per minute. / rinsed
the cloth in coniosl glass, using one
quarter of an ounce of wator, covered the
glass to exclude dust aud allowed it TO
settle for ton minutes. Ono largo drop
Of this water from the bottom of the
glass was taken for observation by tho
microscope. In it | counted los rotifers,
small water animal which delights tO
live and feed among decaying animal and
vegetable matter. Those animals alive are
harmless, but in this case nearly half of
them were dead, and dead animals OF any
szo polluto tho water. The presence Of
these animals in such great numbers in
dicates that there is plenty OF matter
upon which to feed. The death of many
was caused by the exclusion Of light and
air from tho pipes.
There were several of tho Ddphnia puier
or water Aea, which always thrive in con
taminated water and are rarely found in
spring water. In warm weather they
multiply with great rapidity and IL drank
in great numbers are apt to produce
diarrhoca and dyseneery, cases often
proving fatal.
An epidemic of this character somo
years ago ia Boston was traced to them as
the cause.
The most important constituent Of the
drop, however, was large masses of yell
lowish gelatinous substance filled with
green cells and surrounded by thom and
having the long green rods of the plant
OscilidtOrig extending from tho mass and
waving about like the arms of the devil
fish of Victor Hugo. 1t is on record that
persons living near a polluted stream and
partaking Of its water havo, when Ill OF
fevcr OF tho romittent type, vomited large
quantities of this substance which evil
dently developed in the stomach from the
spores swallowed, as the plant resists the
acids Of the stomach.
Tho green cells proved to be one
celled plant, the palmoglea macrOcoccd, q
slimy plant found on damp stones. Bac-
tens were also present in the gelstinous
mass. Taking o pair of sharp forcops and
picking out enough of these masses to
cover white bit Of glazed paper so as to
be seen with the naked eye, and when it
was rubbed smartly with the finger tho
fishy odor became apparent at distance
Of several inches, proving this substance
to be tho source of the odor.
When there is an excessive growth of
this substance, and whether IL be the cells
or tho gelatine matrix that imparts the
odor TO the water and renders danger of
disease imminent, l cannot say. Water
pipes and tho receiving reservoir will
undoubtedly be found lined thickly with
1t. The remedy 10 to clean them out.
Besides this there were peculiar starch
granules in tho water, first seen aud de-
scribed by me in January last, in paper
read before tho Microscopical Society,
aud which l have demonstrated since to
exist only in water polluted by sewerage,
and find that my observation has been
| confirmed by recent investigations OF
the Thames water, near London.
i have examinnd Potomac water near
ly every month for several years, but
never found it so rich in organic matter
as now. l do not say that it is un-
healthy. but it Is certainly in n fair way
| to become so. Thorough filtering through
charcoal filters will purify and make IL
sparkle like spring water.
II A DoRsnN M ID