The Sun.
London, England, 1850-02-08 00:00:00

INSTITUTION OF CIVIL ENGINEERS.

On Tuesday, Feb. 5, (James Simpson,
in the chair) the discussion was renewed on the Rev.
Mr. Clutterbuck's paper, "On the Alternations and
Depressions in the Chalk-water Level under London,"
and was.continued throughout the meeting, so that no
original communication could be read.
It was contended that the area of the Chalk District,
subject to infiltration, for the supply of the springs and
streams uniting in the basin of the Coke, could not pos-
sibly exceed the original published estimate of 1131
square miles, and that the proportion of water filtrating
through, for that purpose, was much less than had ever
hitherto been estimated, inasmuch, as records by Mr.
Dickinson's gauge was to a much greater amount, than
those afforded by the gauges kept by other experimenters.
It was also contended, that the original position as-
sumed in the paper had not been weakened by the sub-
sequent discussion; that the observations of the chemists
had tended to confirm the statement of the pro-
bability of an infiltration of water from the Thames.
The practical conclusion to be drawn from the
observations, recorded in the author's several
papers were :—That the natural drainage and re-
plenishm-ent of the chalk 'stratum might be traced and
accounted for, by observing the alternation of level, in
various localities, and at different seasons. That any
large quantity of water abstracted from the chalk stratum,
at any given point, caused a depression of level around the
point of such abstraction. That in the upper district any
such abstraction of water would interfere with, and
diminish the supply of, the streams, by which the drain-
age of the district was regulated ; and, lastly, that the
depression of level under London, by pumping from
Artesian wells, had proved that the rapidity of demand
already exceeded that of the supply, and that any
attempt to draw a large additional quantity for public
use, would be attended with disastrous consequences.
t was suggested that, considering the great works of
drainage and water supply which were in contemplation
for the metropolis, aed looking to the essential im-
portance of having accurate and authentic geological
information, in order that those great works might
be executed on a sound and certain basis, that the
geological survey now being carried on by Govern-
ment, in a remote district of North Wales, where no
urgent laced exis'el for early geological information,
and where no new works of paramount importance
were in progress, or in contemplation, should he trans-
ferred at once to the metropolitan districts, with a view
to throw light on the real structure, mechanical and
chemical, of the deep water-bearing strata, on which
opinions so varying and so conflicting, had been ad-
vanced

An inquiry was made whether any steps had been
taken by the Connell, in consequence of the sta:oment
submitted at the meeting of Tuesday, January 29th,
urging the consideration of the manner in which the in-
terests of the public at large, and of the profession, were
likely to be affected by the attitude recently assumed
by the Ralway Commiss'en, in reference to the strength
of the wrought-iron bridges used on railways.
It was stated that the Council had not as yet" taken any
decided steps in the matter, but that a course had been
suggested, which, being followed, would most probably
lead to sati.factory result:.. Atter this assurance the
members expressed their cenfidence of the interests of
the profession being in safe hands, and that every step
would-be taken for insuring their position and profes-
sional reputation.
The motion which had been prepared, was therefore
withdrawn; and the Chairman requested any commui-
cations on the subject to be made in writing to the Se-
cretary, who would lay them before the Council.
At the monthly ballot the fillewing candidates wore
duly elected:—R. S. Haggar, R. Murray, J. S. Peirce,
G. Sibley. H. Smith, and W. Strode, as Associates.
The paper announced to be read at the meeting of
Tuesday, February 9th, was " On the Theory of Trans-
verse Strain, with Rules for calculating and construct-
ing the strength of Cast Iron Beams of different forms,"
by Mr. W. T. Doyne, Assoc. Inst. C. E.