The Providence news. (Providence [R.I.]) 1891-1906, 1894-08-07

Q system. In these experiments he used
!. inter bed two feet, six inches i'm dent
1 ana the public would be interested I,
Q know with what success he met
Q Inc shallow filter beds o.
! Lambeth, Grand Junction and South.
walk, London, averaging feet inches in
. depth, showed mean average for the
= year 1891 to 1892 OF 319 bacteria per cubie
, centimeter In the filtered water "a against
, III bacteria per cubic centimeter in the
filtered water from the CbeIsea
and West Middlesex, London. supplies
the beds of which have an average dent h
of4 feet Az inches. The filter beds at
Berlin are feet 9 inches in depth. those
at Warsaw, feet; those at Zurich, feet /;
those at Lawrence, Mass, s feet. Mr..
Shedd has not yet explained what pro.
visions he proposes making for subsiding
basing In connection with his filter plant.
by which the intake from the river can be
closed, an absolute necessity for Paw.
tuxet water, as the experience of the city
has already shown, or whether such pro-
vision Is covered by his estimate. Saws
that noted chemist and engineer of the
Metropolitan Water Supply of London,
DIR. r.. Frankland: "The fact that the
impurity OF the water in the rivers is so
largely increased during periods OF flood
water renders 1t of great Importance that
there should be sufficient provision of
subsistence and storage reservoirs to en-
able the necessary daily supplies to be de-
livered during such periods, while keep
ing the intakes closed. Such provision is
essential Tor securing uniformly effective
filtration"
The report Of Mr. E. b. Weston, M.
] Am. " T., under whose charge the ex-
periments at the Pettaconsett Station
were maze, IL Is much to be regretted has
not yet been published, and accordingly
no oetaiied comparisons between the me-
chanical and natural filtration results
there obtained can be given; but that
this carefully prepared and valuable
report was not unfavorable to the
mechanical method Is vouched for
by the following statements made before
the City Council by officers of the cjtv
who were familiar with the contents Of
the report. In answer to Mr.. Burdick,s
question: "What percentage is removed
by the mechanical process?D Mr.. sbedd
replies: From 50 to 90 per cent. of bac-
terra, and the color is about half re-
moved"
Q.-"How much OF the organic matter |
upon which the bacteria live will be re- |
moved?"
A.-Mr. Shedd: "Practically the wbole.n
Q.-"What advantage has this over the
so-called Natural Process at LawrenceY
DO they get better results?"
A.-Mr Shedd: "No, think not. The
results are practically the same"
Q.-Mr. j. NJ. Kendrick: "Does this mo-
chanical filtration meet with your own
approyalfn
A.-Mr. Shedd: "At first was afraid
that 1t would not accomplish the work,
put the experiments that have been made
nave convinced me that the system is al
together adequate"
Testimony Of Investigators.
In answer to questions, DR.. Charles V.
Chapin, superintendent OF the board of
health OF the city of Providence, said:
" The filtration Of the water would remove
~ per cent. OF the bacteria, and it doe,
more; it removes the sus-
pended and dissolved organic matter
oi the water upon which the bacteria
eed, SO that what few OF them NAV
get through the filter will die for want of
iourlshment before the water reaches The
consumer. The additional advantages are
ne removal OF alg@, ETC., and the better
oior OF the water. As TO the question of
ne relative advantages OF natural versus |
nechanical systems, | am strongly in |
avor OF the mechanical filter. 1t will re- i
nove the bacteria fully as well, and IL i
VII remove the organic matter much .
etter. Not the slightest trace of i
mat we call 'sulphate of alumina II
ONES through. The effect of the alum &
itered water upon the boilers is not Mt
mi -, |
cial. The mechanical filters are used in
} many as fifty American cities, and in
,me instances have been for many wears.
have visited these cities and made en-
uiries OF the health officers as to the re- 4
lit, and have never found any case of
sease attributed to the use of the
ater."
Dr. Swartz OF the Rhode Island Board
Health said he was greatly in favor of
10 mechanical system of filtration. In
% natural filters there is one serious OBJ r
ction the top OF the filter bed must be-
raped as the impurities in the water
tile upon the bed, forming a
TX, shiny sediment, which clogs
the hitter, preventing the
'e passage OF the water. In order To ~
operiy clean this, the lsborers are forced
walk upon the bed, and the impurities -
on their boots from the neig boring
and land thereabouts Is thus
'und deep into the filters whence comes
drinking water OF the city,"
'lf. Il. Is. Weston. M. Am. &. E., of tho
engineers department, stated ne
been In charge OF the tests for the -.
u 10 months, and that at the start he "
prejudiced against mechanical filtra-
q. AT the conclusion of the expert
nts, however, he was very well satisfied
n the result. In his opinion, a natural 4
or plant would cost twice as much as a SE
chanical plant. The figures were ar
"a at by estimates, and tho total cost
he natural filter plant, he gave as five
ldred thousand dollars $500, ,o0o). The u;
OF covering the bed, would, he should hh
be about seven hundred thousand -
srs sloo,oOo.0oJ, (ilters includcd). n
'aid rather remarkable results had been
aimed byt ,ents at Pett.cos III
and ever. n M could bs tbon,s.
ihu oc-n A. The reaulf. ~ 1h