The Press.
London, England, 1858-07-10 00:00:00

Witness ; My answer is this—that in Glasgow a
portion of one of the sewers receives into it the re-
fuse of certain chemical works, the effect of which is
that the whole sewage matter into which that refuse
falls becomes deodorized. Ido not know the reason ;
I only know the fact.
The CLIAIRMAN : Hence you infer that some disin-
fectant or some solvent matter might be found out
which would remedy the evil?
Witness: Well, it may be so; that, at all events,
is a thing which is going on every day there. My
attention has been frequently called to the state of
the sewers in London. _ .

Mr. Joint; 'AWES gave evidence as to the levels
and capacity of the proposed embankment tunnels
for precip;tating and deodorizing the sewage. He
explained that two tunnels were proposed to be con-
structed, one at low level, the other at high level.
The sewage would flow into the low level tunnel by
gravitation, and it would be raised into the high level
tunnel by pumping. The two deep culverts would
be considerably above the sewers; one was to receive
the sewage from the high level, and the other from
the low level. He would apply the lime to the sewage
as it runs into the tunnels. He would not allow the
sewage to become solid, but would make it a sort of
sludge, anti pump it away through pipes; and it
would be deodorized. There was nothing in
chemistry which could be applied to sewage so as to
separate every impurity from tho water. The system
pursued at Leicester was by deodorization ; that
pursued at Cheltenham was by filtration. Witness
did not recollect what was the area of the works at
Leicester. It was not an acre. The scheme could
not be adopted in the metropolis for want of space.
To meet that necessity, therefore, it was proposed
that there should be an embankment, and that
within that embankment there should be two reser-
voirs into which the sewage should be discharged.
The bottom of those reservoirs would be a little
below low water.

Sir B. HALL here inquired : Have you and your
co•commissioners come to a conclusion that the out-

fall from the various sewers will run into your
tunnels,—that they will be able to contain the whole
sewage, without altering any of those contributory
sewers ?

Witness : I think you had better put those ques-
tions to the engineer. lam not an engineer myself.
The CRAIRITAN : I understand that the witness is
speaking from the report.
Witness : Yes.
The CHAIRHAN: The engineering part does not
coma within your knowledge?
Witness: No; I am speaking of the chemical part
of the report.
Sir B. HALL: This point being at the root of every-
thing, it must have been brought before the Com-
missioners. Supposing the bottoms of your tunnels
to be level with low water, and the sewers are some
18 or 20 feet high, how far do you mean that the
backwater should flow? The sewage must flow
back somewhere ?
Witness I think the sewers have stop-gates, but
Ido not know. I know, however, that the question
was fully discussed by the Commissioners. I think
it would be advisable first to proceed by deposition,
and then by filtration. I believe it to be practicable
to work by filtration, according as the tunnels are
now yroposed to be constructed. Filtration, how-
ever, is merely a scheme to save the expense of lime.
There would be 400 tons of sewage deposited in a
solid state daily. This being rendered soluble and
increased at the rate of 1-50th, might be carried off
daily by steam through pipes three feet in diameter.
Of course, this could not be done unless Government
purchased some waste land, on which the sludge
could be deposited. It might, however, be pumped
into the sea; but, supposing it were required to be
used as manure, then it would be necessary for some
place to be obtained to which to carry it. There
VMS some very bad land at about twenty miles dis-
tance, on the South• Western Railwa3.
By Mr. PERCY : Witness thought there might be
apace enough at the mouth of the Ranelagh sewer to
make the experiments suggested for precipitating
and filtering the sewage. He was not aware that
iron pipes, by which the sewage was proposed to be
conveyed away, would very soon oxidize. lie was not
aware of any experiment as to the effect of London
mud upon iron.
By Mr. Loritz : The precipitate at Leicester is
almost valueless as manure ; but that means that at
Leicester they cannot sell it at a high price per ton.
If, however, you have to get rid of the substance for
sanitary purposes, and can do so by purchasing bad
land at some 101. or 151. an acre, and thereby make
that land valuable, it may he better than pumping it
into the sea, for get rid of it you must in some way.
By Sir J. SHELLEY • The land on which the sludge,
would be thrown would be capable of being brought
into cultivation about a year after. The taking away
of the sewage in a concentrated state by barges would
certainly be more difficult than to convey it away in a
diluted state by pumping.