The Express.
London, England, 1864-03-25 00:00:00

THE SHEFFIELD INUNDATION.

CONCLUSION OF THE INQUEST.

The inquest ryas resumed yesterday morning in
the Sheffield Towa•bell, before Mr. J. Webster, the
:oroner.

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Mr. R. Rawlinaon and Mr. N. Beardmore, government
2Dgineen, represented the Home-office ; Mr. Smith (eon-
citor) represented the Sheffield Waterworks Company ;
ind the Mayor and Mr. Yeoman, the town-clerk, appeared
for the corporation. Amongst the gentlemen on the bench
were Sir John Gray, chairman of the Dublin Waterworks
t•aupeny, and Mr. Neville, the Dublin city engineer.
At a late period of the day on Wednesday Mr. Raw-
boson made the following remarks. He said—Mr. Holmes
has got a map and has coloured the entire tract affected by
the flood. He has also ascertdoed that the total fall of the
river was 450 feet from the Bradfield Reservoir to Owlerton,
or 72 feet per mile ; and he has calculated that the velo-
city of the flood was no less than 18 miles per hour, or 26i
',et per second, approaching an area of the cross sections
between the4same points of 3,,80 feet, or 40,170 cubic feet of
water mains every second. This rate would empty the
reservoir in 47 minutes. The force of the water was really
tremeodona, and perfectly inconceivable. There are viz and
a quarter gallons in • cubic foot of water, being 101bs. per
piton, or Gibs.) per foot. The velocity of the flood was
something awful, and after the dam bunt not even • Derby
horse could have carried the warning in time to save the
people down the valley.
T. M. B. Jackson, of Sheffield, civil and rrechanical engi-
neer, said-1 have often been engaged in the construction ci
reservoirs in Australia. 1 was chief engineer of the Mel-
bourne Waterworks, consulting engineer of the City of
Adelaide Works, consulting engineer for the Ballarat Cor-
poration Works, and first engineer of the Beedigo Works.
1 was on the embankment at Bradfield on Saturday. I
have examined the works three times since—ones with
special reference to this inquiry. lam of opinion that
there is no fault to be found with the material or the dopes
of the embankment, although in my own practice I should
have preferred a slope of three to one. The puddle em-
aloyed in the embankruert is good, aod quite truffle* ,t •
nd I have no fault to,find with the weir. I have examined
the structure of the embankment csrefully, end heard tram
the evidence yesterday how it had been formed. I should
not have formed an embankment in the isms way myself.
I should distinctly prohibit the use of waggons and rails '
upon a bank of that kind, moss especially on the inside
slope. 1 object to them on the inside because, in the first
place, I should use layer, of about two feet thick ; and •
railway waggon always travelling on the same
line tends to unequal consolidation, while band-earte
travelling all ways would have a contrary effect.
I should have insisted that each layer of two feet should be
perfectly honked before another was commenced. On the
outside slope 1 would not object to • tip of three feet,
because it is not so necessary for theouteremhankment to be
impervious ; in fact, it is rather better to be open, because
the water then ha. free exit. By open I mean it should
be composed of more porous materials. The embankment
at Bradfield has not been erected in that way. There are
railway waggons upon it now, showing that the) have been
used there ; and it is obvious that the layers of earth have
been laid on at a greater distance than two feet. I have
seen the reservoir at Agdeo, and there the bank is built on
the same principle—one layer is not finished before the
other is commenced. If the reservoir at Bradfield had been
constructed the same as that at Again, I should apprehend
that there would be an unequal settlement, which of course
is dangerous—dangerous because it is Labia to cause • slip,
and peculiarly dangerous if • pipe is passing under the beak
through a puddle trench. The beet plan I have seen is that
or Mr. Leslie, of Edinburgh, who advocates tips restricted
to six inches, evenly spread over the whole surface, each
layer being finished before the next is begun. I also
of Mr. Leslie's stipulation that the puddle wall should
brought up to and kept six inches above the adjoining por-
tion of the embankment. In my works at Melbourne we
bad two fractured pipes under the embankment, but in the
grouol
Mr. Rawliesea—Do you mean the same as at Bradfield?
Witness—No, the pipes were laid on flags up to the edge
of the puddle trench, and in passing through the puddle,
each piped each main, which was only six feet six inches
in length, was supported on an ashlar pillar. No doubt
these pipes were fractured by unequal settlement of the
embankment, although made in even layers. There is no
question at all that a bank will settle more in the middle
than at the
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