The Sun.
London, England, 1852-09-29 00:00:00

// Z /dC ie - d

RAILWAY INTELLIGENCE.
SOUTH WALES.

FLOATING OF THE SECOND GREAT TUBE
ACROSS THE WYE, AT CHEPSTOW.
Extensive: preparations have been making, for
some days past, towards floating the second great
tube for the second line of railway across the Wye,
at Chepstow, which was accomplished yesterday
morning. Mr. Brereton, the intelligent assistant of
Mr. Brunel, the engineer, has been unremitting in
his attention to the works in the absence of his prin-
cipal, through indisposition, in Italy.
Previously to the elevation of the first tube, on the
19th of July last, the passengers by the South Wales
Railway were conveyed from Chepstow west to the
other side of the Wye, in omnibuses, &c., over 3
stony and disagreeable road, about two miles in
length. Up to that time, also, there had been no goods
traffic into Wales, or from that country—thus with-
holding a large weekly revenue from the shareholders.
The formation of the railway across the river, how-
ever, removed this difficulty, and also increased the
passenger traffic, SD that since that period the revenue
of the company has increased soma .SCOI. or 6001. per
week. Tne further opening to Carmarthen (not yet
sanctioned by the Government inspector, thouqh per- •
formed by the directors on Friday week) will ineee ase
the revenue by a considerable amount, and perCeu-
larly in the goods traffic department.
The bridge at Chepstow, when the double roed way-
shall be completed, will form one of the most magni-
ficent objects that scientific men, engineers and other?,
will desire to look upon. The river Wye is one of
the most picturesque of our English or Welsh rivers.
Its banks abound with objects of classic and varied
renown. The celebrated ruins of Tintern Abbey lie
on its left bank, a little way below Chepstow. The
ruins of Chepstow Castle, almost contiguous to the
railway bridge, on the right-hand side of the road
from London, can easily be observed by the traveller
or tourist frowning over the bosom of the " beautiful
Wye ;" while the bridge itself, towering high enough
above the river to allow tall ships to sail beneath,
will not be the least attractive of the spectacles abound-
ing so profusely here.
The Wye is a rapid navigable river, upon which
there is considerable traffic. The Admiralty, it may
be remembered, when the project of a bridge at this
particular point was suggested, refused to sanction
any structure that should not have a span across the
river of 300 feet, and be elevated no less than 50 feet
above the highest spring tides. In strict accordance
with this resolution the railway bridge was laid down.
Its full length, from the westward embankment to
the eastern shore of Gloucestershire, is 600 feet.
There are three 100 feet spans on the Monmouthshire
side, upon the land, supported upon cast iron cylin-
ders, 1 inch thick and 6 feet in diameter. The
aver
age depth to which these cylinders were sunk
was 48 feet, through strata of clay, quicksand, marl,
&c., down to the solid limestone rock, which was
found to
dip at an angle of 45 degrees. There was,
consequently, careful horizontal levelling, and the
cylinders were bedded level. The sinking of these
cylinders was a
work of much difficulty. EXCM,
tions were carried on within them, and they were
enginewhich wasw a s alsoon st
arhetql
yu
kt o.
pressed down
by heavyweights.' A 90-horse
the rising of the high tiadeisngremarkable
fact, that although the i pumpe s
p outeespecially
I. a
lt
ihye
duringwater,
It. was a
tater
was not found in these
Wye
siin:itidal river sal
having been sunk were filled withngas.
Port-
land cement, gravel, and sand,
Whicheosnetcre.te of Pot
as hard as adamant. Six pillars thus formlnd
upon the Monmouthshire land, upon which quickly,
The cylinder`
the
now
line was laid, together with one of the girders feor ther
second line. The three cylinders upon which the
other girders, together with the road for the second
line, will rest, have been sunk, but do not come above
the level of the ground, so that their continuations,
which are lying on the yard in a complete state, have
yet to be erected. The tube itself is 300 :feet long,
to cross the full span of the channel. At every third
part of the tube Mr. Brunel has introduced a stiff
wrought-iron girder, which connects the tube firmly
with the road girders. To the ends of the tube are
attached the suspending chains. These, with the aid of
adjusting screws, and the wrought-iron girders on the
tube are stretched as nearly straight as could be de-
sired. There are other diagonal chains connecting
these points, so that at whatever part of the bridge
an engine may he passing, by the arrangements
described its weight is fairly distributed over all the
tubes and chains.
When this second tube is completely elevated,
which will be performed by a slow process, it will be
fixed upon the iron standard on the Monmouthshire
side; and on the Gloucestershire side will be free to
move upon rollers at the top of the masonry standard,
according to the expansion to which it may be sub-
jected, though the greatest expan-ion the fellow-tube
experienced on the hottest day did not exceed one
inch. Tne tube is apparently a slight structure.
Within, it is strengthened by the introduction of
diaphragms or discs at every thirty feet, rendering it
both light and stiff. The girders for the roadway
are formed of a deep thin plate of iron, stiffened at
intervene There is a strong triangular cell at the
top to resist compression, and extension is resisted by
a double plate of rivetted iron at the bottom. The
girders upon which the road is to be laid will be laid
diagonally and rivetted; while upon them creosoted
planks will be secured in the contrary diagonal direc-
tion—thus producing a stiffness and security. Above
these planks eighteen inches of gravel will be laid ; and
then, upon longitudinal sleepers, the permanent rails
will be fixed.
The extent and ponderosity of the works may be
gathered from the following statistics, furnished to
our reporter by the efficient manager of the works :
Tons. Cwts. Qrs.

Two wrought iron tubes, each 312 feet
long 302 11 0
Wrough iron beam on tho standard, to
support the tubes ...
Wrought iron, in three spans of 100 feet
each, double line ...
Wrought iron in the girders, floor-
bearers, and other works, of the main
span of 300 feet, double line...
Vertical trusses ...
Tie girders to connect the column caps
Suspending links in the main chains and
diagonals 256
Saddles at points of suspension ro 11 CTS..• 41 10
Adjusting screws 2 10 0
Main tube rollers 7 17 3
•••
Rollers of girders 2 11 3
..•
Rohs 315 0.• ..•

20 5 0

... 277 0 0

278 6
37 0 1
1 10 0

1,231 2 3

Total wrought iron

Ditto
Cast-iron bar plates for trusses ... 24 6 1
Ditto standard . "' ...
128 6 0
caps for column and
g piers .•. 830 0 0
Ditto cylinders in supporting parapets ... 21 0 0

Total cast iron ...

~. 1,003 12 4

Total of wrought and cast iron... ... 2,234 14 4
The masonry in the abutment and pier is calcu-
lated to contain 3,240 cubic yards, and the total coat
.)f the bridge complete, 65,420/.
The floating of the immense tube was a work of
::omparative ease, so perfectly had Mr. Brereton ar-
ranged his plans. A railway was formed upon the
land to take the tube from where it had been tested on
to a railway formed on piles, extending about 300 feet
out to the iron standard. There the end was taken
upon a floating raft of three iron canal boats, inverted
upon another three, forming pontoons. This raft at
the highest tide yesterday morning was floated to the
other side of the river, the tube gradually leaving the
land railway, and occupying exactly one hour and
ten minutes in its transit. When it extended its
great length the full width of the river, a powerful
tackle was fixed to the end, and the work of lifting
commenced, amidst the cheering of a large number of
persons who had assembled to witness this trium-
phant undertaking.
The work has been carried forward under the
talented superintendence of Wm. George Owen, Esq.
&c., had been made under Mr. Brunel, '
the resident engineer, assisted by Aiessrs. Sayers and
Dibbin. All the elaborate calculations, d wings.
assistant in London, Robert P by
Brereton,
P. Esq.
Messrs. Finch and Willey, *
Liverpool,
were the con-
tractors for the iron work Sharpe, who is
; and Mr.
and Pembrokeshire, was
now engaged in the contract firs able
between Carmarthen
the contractor for the
masonry.
Among
those present to witness the interesting pro-
ceedings were Mr. I. K. Brunel, the engineer; Capt.
Claxton, R.N.i Mr. Frederick Saunders, secretary
;
to the Great Western Com Pan
Jones, C.E i ; Lieutenant San-
ders, Mr. W. Alr. d wards' C.E., Mr.
Dorn, C.E. Government
Mr. Brodie, C.E., and the ,
Inspector, Captain Calton, who, with Mr. Brunel
and Captain Claxton, were upon the platform at the
end, superintending the important works.
The process of lifting began at a quarter past-eight,
on the Gloucesterhire side, and will probably occupy
about a week. We are glad to say that not a single
accident of the slightest kind bas occurred throughout
the whole of the proceedings.

PLYmOUTII AND TivisToca.—At a meeting just
held at Oakhampton resolutions were passed recom-
mending
.conferencas with the authorities of Barn•
staple, Bideford, and other places, to ascertain thelr
probable support, and the amount of traffic likely to
pass over the line from Plymouth to the North of
Devon.
LONDON AND NORTH-WESTERN.—It i 8 stated
that Mr. Glyn is temporarily succeeded by Mr.
Smith, as chairman of the board of this company, Mr.
Glyn still retaining his seat as a director, to advise
and give information.
HATFIELD AND IiToN
the district to the construction of a line. from La=
uport of the landowners of
are being
made to obtain the support
to Hatfield, which is intended to forma junction with
the Great Northern Railway.