The Sun.
London, England, 1864-03-24 00:00:00

THE SHEFFIELD CALAMITY.

ADJOURNED INQUEST.
The inquest on the bodies of Thomas Elston and other'
was resumed at the Town-hall yesterday.

The Coroner (Mr. J. Webster) conducted the inquiry.
Among those present were Mr. Robt. Rawlinson, C.E., and
Mr. Nathaniel Beardmore,:C,E., from the Home-office ; M.
Mille, member of the Legion of Honour, and engineer of

bridges and roads to the French Government; Mr. Robert
W. E.C., F.R.S., of London; Mr. W. Lindley,
C.E. (London), engineer of the Hamburg Sewage and Water
Works ; Colonel Ford, of York ; Mr. Perrenet Thompson,

barrister, instructed by Messrs. A. Smith and Sons, solid•
tors to the Water Company ; and Mr. Wm. Smith, chair.

man of the Water Company,

The Coroner, in opening the proceedings, 'said the jury
were met to inquire how Thomas Elston and others came
to their deaths on the 12th inst. He proposed only to direct

heir attention to the death of Elston. Separate inquiei-
ione could afterwards be made with regard to the other

deceased without any particular inquiry. Having read the
evidence taken on the previous occasion, the coroner added
that the course he proposed to take was to examine the en-

gineer of the company first, in order to get as far as possible
a history of the embankment. If Mr. Leather could not
give all the information deemed necessary, he (the coroner)
would examine Mr. Gunson, the resident engineer, Mr.
Craven, the contractor, and such other witnesses as might

be necessary. If their evidence was not satisfactory, he
would call Mr. Rawliuson, the Government inspector, and
one or two other witnessses who had been engaged in ex-

aminin,g the reservoir, who would give their opinions upon

the cause of the disaster. That would be the most direct

way of getting at what they wished. lie hoped to be able
to conclude the inquest that day, but if the witnesses were

not all examined by half-past five he would adjourn the
proceedings and resume the inquiry this day.

The following evidence was then adduced :
Mr. John Towlerton, Leather, Leventhorpe, near Leeds.
civil engineer, said—l am the consulting engineer of the
Sheffield Waterworks Company. I was consulted by the

company when they applied to Parliament for powers to

make the Bradfield reservoir. I prepared the plans and

specifications for its construction. That would be in the
year ISSB. Parliamentary plans and sections were deposited

in 1852 for this and two otter reservoirs, which we called
the Bradfield scheme. I examined the country generally
before depositing the plans, to see if water could be obtained.

The contract for the Bradfield reservoir was let, I think, in
1858, Originally the embankment was set out lower down

the valley than where it is executed. The first embankment
was never commenced, because it was found, on trial holes
being sunk, that there had been a disturbance of the strata.
I then altered my plans for the embankment to be where it

now is. I examined the grwund before we commenced mak-
ing the embankment, and found it to be on the out crop of
the coal measures, and at the commencement of the mill-

stone grit. The strata consist first of soil, then clay, then
stone, then shale, with a Bannister formation and a little
coal in the centre of the valley. I had to deal with soil,
clay, stone, and shale in the embankment. The only spring
I ever saw in the valley was one on the site of the reservoir,
a little above the embankment. The first thing in forming
the embankment is to sink the puddle trench in the centre
of the base. The original plan provides for a puddle bark
about Ifift below the surface. In sinking a trench we did
not find a good foundation at that depth. It was not suffi-
ciently water tight. It was th,trefore necessary to sink until
we did get to a water tight foundation. We sank to a depth
varying from I.Oft to 60ft, and then got a water tight foun-
dation. A good deal of water came into the puddle trench
during the working. Wo got rid of it by pumping. I do not

remember what powers the contractor had to pump the
water, I came to see the trench, I think twice. I came when
I was wanted. I walked over the bottom of the trench when it
was finished, and knew it was water-tight. I am not aware
that in wet weather the quantity of water in the trench was
so great that they could not pump it down. I saw the
puddle trench in 1861, and in 1863 I saw the puddle wall.
I did not see the puddling of the trench in its progress—at
all events not at the lowest point. I did not see the whole
of the puddle, but what I did see was well put in, and the
work was good. The water was not cut uff altogether from
the trench. The trench simply divided the watercourses.
The water came into the trench so long as it was open. The
bottom of the trench was impervious, but the sides were
pervious. The water was not got rid of, but blocked out by
the puddle, as is usual. When, therefore, the puddle wall
got to a certain height there would be water against it on
the upper side. The water that would get through the rock
to the puddle wall would not have a tendency to injure it.
The object of a puddle wall is to keep out water, and there-
fore water is always against it in a reservoir. The water
rises against the puddle wall, but does not percolate through
it. The water was not let off by any natural means ; if it
had the puddle wall would not be perfect. As the puddle
wall was being constructed, the water rose with it, and was
carried away. The embankment across the valley is 418
yards long. It is 500 ft. wide at the base and 12ft. at the top.
The inner slope is 21 to 1, and the outer slope the same,
The greatest height is 95ft. The puddle is 4ft. wide at the
top, and gets wider by 11in. at every foot in depth. Thus,
supposing the puddle wall is 95ft. high, it will be 16ft. wide
at the base. There is 60ft. of puddle below the surface, mak-
iug the total depth of the puddle wall 155 ft. The reservoir
would contain a little over 114,000,000 cubic feet of water.
The surface area of water was about 78 acres. The area of
the gathering ground is about 43,000 acres. We got the
material for making the embankment from the inside of
the reservoir, and in doing so laid bare the rocks. In
some places we got a good deal of stone. The embankment
is made of stone, clay, shale, and earth. I cannot say how
the material was put in. Mr. Gunson was not my servant,
He was the resident engineer. He had the snperintendence
of the works, and occasionally consulted with me. He could
not deviate from my plans. There are two IS-inch pipes
from the inside to the outside of the reservoir underneath
the embankment. The pipes are about 500 ft long, made up
of lengths of 9ft. There would be 55 or 56 lengths. They
are joined with sockets and lead in the ordinary way. They
are laid in a trench Oft below the surface of the ground.
They aro wrapped round with clay puddle to the thickness
of, I think, 18 inches, the trench being then filled in. The
pipes are laid obliquely, not diagonally, across the embank-
ment in a straight line. The valves are at the lower end of
the pipe, outside the embankment. If one of the pipes were to
burst in the centre it would be difficult to get to it to repair it.
It would have to be reached by excavations. An instance of
that kind occurred in the great dam at Crookes. The pipes
were originally of wood. I removed them by excavating,
and substituted iron pipes. They would be 30 years ago.
The breaking up of one of those pipes would most likely cause
serious damage to the embankment. The embankment might
possibly fall before we could find out the damage ; I can't
tell what might happen. I never knew an instance of that.
Ihe pipes were made of double the usual strength. I should
think there could not be an unequal pressure upon the pikes
from the embankment. Being laid in the solid ground,
the weight above could do no harm, unless it was a crush-
ing pressure. There would not be en unequal pressure
upon the pipes so as to raise them at any of the joints or
cause them to leak. We can insure a suffici nt equality of
material along the whole length of the pipes, for all practi-
cal purposes. The -Water Company have other dams
constructed on the same principle which have been in
operation a great number of years. Possibly water from
the sources blocked up in filling the puddle trench
might get into the pipe trench. If it did it would show
itself. If water got in below the pueldle trench it might
be dangerous; if above, it would not. It would show
itself by percolating to the lower end. Water-mains
in streets do not often give way under external pressure.
I never knew one break or yield at the joint from external

pressure.
Dlr• Rawlinson—ls it not a common thing for a new line
of mains to have blemished joints and leak?
Mr. Leather—The pipes of the company are severely
tested before they are put down.
Mr, Rawlinson—l saw the testing apparatus, but never-
theless the question is a proper one. My experience is that
they do give way.
Mr. Leather—My experience on the contrary is, that they
scarcely ever do give way.
Examination of Mr. Leather by the Coroner resumed—l
never hsard of a pipe giving way on account of water creep-
ing along the pipe trench. Ido not know there was such a
case at Birmingham. It would not have been better to have