Burlington free press. [volume] (Burlington, Vt.) 1827-1865, 1859-08-19
From the Montreal Transcript.
THE LAST PIER OF THE VICTORIA
BRIDGE.


the Victoria Bridge, was pumped dry ul
Wednesday. and that the event was dgl'
celebrated hya numerous party Of The friend
Of the contractors. This. the last dam-WJ
commenced on the 18th OF May and pumre,
dry on the > inst. The mad and loose 1r,v
el which lorms the bed Of the river, has still
to be removed. however, in order to ct 6,
/ the rock for the foundation of the pier. Ihi
! involves an additional excavation Of from : T.,
! 9 feet. II is expected that the whole of th.
/ mass of masonry will be finished and ready
! for the placing Of the tubes in six weeks from
this time Tins last pier, No. II from tn,
/ Montreal side Is estimated 10 contain, when
completed, about 1000 cubic yards of ma
! sonry. The stones are all quarried and cut
to the requisite dimensions at Point ST. Claire.
/ The piers ar built in deep water, which has
| a fall of one foot in fifty, and consequently "a
very rapid current The Golfer dams have
used up about \ GEO feet Of pine exclusive
Of the piling, and contain about 543 900 gal
Ions IF water This on. was pumped ouJ in
about 5 hours. 4 contemporary says:
No one who has not witnessed the extent of
work required for such a structure can conceive
"lth any thing like precision OF the mul tilariUus
and persevering labors involved in lis execution.
that water-tight chamber, of dimensions ] re
enough I" contain the pier, has to be formed IN
water OF 20 L p feet deep, with rreg liar b.t
tom and IN current running (per lo-) 10 miles
An nour. The process by which this is elected j.
first by sinking barge Of 60 feet in length loaded
with stone, at distance in advance of e iu-
tended pier. This serves for a break-water. y ext
another break water, formed by crib-w,r and
loaded with stones, is sunk still nearer, IN fact In
Immediate proximity TO the site OF the pier Then
comes similar protection call a " heading" Ia
the eddy formed by this heading the Golfer Dam
is made. Ii is constructed by sinking frame Of
horizontal timber TO the bottom; by driving out
side and all around this row Of piles which ar,
st enlightened once more by horizontal beams. This
forms the inside wall. A d outside wall some L
feet distance is then formed in similar way, and
the interval is filed with clay rammed hard. ltis
a moment Of considerable anxiety and excitement
partsken in by all engaged on the work, when the
pudding is reported comp etc, and the attempt ia
made 10 free the interior of the dam from water
so many unseen incidents may have occurred, that
nothing but demonstr ton i. enough to prove that
the Dam is really " ter-tight. We saw more than
one pile which, having struck q boulder,
diverted from its course, and had its lower end
projected into the interior Of the chamber. No
evil had resulted from this circumstance; but flaws
Of various X nds are not uncommon, and, of course
any one, however small, is at once found by the
pressure Of so great body Of wat9r. Springs, too.
not unfreque tly rise up out Of the bottom of the
Dam. In this case the pumps drew Il once, and
the Dam Is as tight as it is possible 70 make 1t.
The next difficulty arises from removal Of the
loose stuff at the present bottom. This, # c"urro
eaLens the f,undation of tho Dam, and may otter
an entrance TO the water Should every thing g
right the masonry will be commenced in a week
or light days and, as have stated, the pier viii
be finished in five OF six weeks
The centre tube is $50 feet long, and is el-
+,1 go l., ( FL
1t contains instruments for measuring its ex-
tansIon, contraction and detection, occa-
stoned bv cold and heat and the result of
the observations is that each degrees of
temperature expands or contracts 1t one
tenth Of an inch IN a run of 2I2 feet. the
greatest variation being three inches and "a
quarter between 100 : above and SO below
Zero. So sensitive are the tubes to heat and
cold. that they are never at rest; a cloud
passing over the sun is sufficient to affect
them but these variations are provided
against by the tube being allowed to extend
or contract itself at pleasure upon rollers, a
sufficient distance being left between the
tubes for this play. The greatest dehetion
Of this tube caused by temperature has been
half an inch, and the greatest rise one inch.
The workmanship Of the tubes is OF the very
best character, and has only to be protected
from the influence of the weather by a sufi-
cient coating of paint. In the building OF
the tubes the greater part Of the rivetlng is
done by machinery. The process Is rapid
and the work complete. The plates to be
rivetted have the h les ready punched. Cold
rivets are inserted in some Of these holes, 50
as to hold the pieces together temporarily
They are then suspended from a traveller
which runs between the two parts of ID riVet-
ting machine. Thus u lateral motion may
be communicated by the motion of the tray-
eller, while a tackle raises or lowers the
plates A furnace is close at hand, where
the rivets are heating. Boys place them in
the appropriate holes, and the head Is then
adjusted against fixed hammer head, and
another hammer head, moved by a hydraul-
ic press, is Immediately put in motion by
the turn Of screw This drives the bolt
through. making the head simultaneously.
In this way a rivet is set in its place III
very few seconds. The rivets themselves are
made in a similar manner. There ARE Is
tubes completed, and seven yet to construct.
The scafoldings for three of them are placed.
The whole of the tubes have been imported
from England. The greatest activity pre-
walls, and ifno untowar circumstances inter
vene, the bridge will be finished by the time
specified.