The Express.
London, England, 1859-05-04 00:00:00

TILE ALBIRT VIADUCT AT SALTAEIL

The ceremony of opening the etapendoui viaduct
at &hash, which now establisoes a reilacy conammication
woes the Tamer, between the comities of Devoe and Corn-
wall, wee performed on Monday by his Royal Highness the
Prince Consort, ea we briefly mentioned yeeheu• y. The
owed= was an unusually auspicious one, not ilea became
the Albert Viaduct is regarded sa one of the moat wonderful
aigineerkig works of Its kind in existence, but elan became
it establishes the Bret railway communication between two
important counties end the rest of Distend. Though, as we
have said, the Salted bridge may rank as one of the engi-
neering wonders of the pierce day, it is remarkable with
what little interest, except in the engineering
world,' the progress of the work bag been te-
✓adad. Though Cornwall has from the most remote
=lied es the most imprtant mining county in the
, the mews of communication between it and the
neighbouring meaty of Devon have been most defective. The
vast width of the Tamar at Plymouth (which was the prim
ripel highway into the ormaty), and the abrupt end broken
nature of ths Confab bile, VIM foe a long time considered
Insurmountable obetsslee to the formation of a line of rail-
way. On the formaden of the Cornwall Railway Comps),
boweere Mr. Brunel undertook the arduous took of over-
siVrig &Meddle which barred the cos•
eles, and the skis manner in which he bee
performed the work has waked the admiration of the Kier
title world. in the short dirrtaneset GO mike there arentrkaw
than ewireatimmaiseedeevieduciesersieleiweichareurrartim
at lio.llsiqabdelit. The iramotexktillsalty, briefer, teethe

eriefieg the lies sense the breed estuary and mile; cf the.
Teaser, which et its narrowest pert iv nearly lull a mile In
width. The spot fixed upon for the bridge wa3-teer the GM
and owe important town of Salteab,mbees the bread input's
of the river Tamar is contracted between lofty bile to about
the width of the Thames at Westminster, though from point.
to point of the hills on either aide, SCTOSO which of course the
Viaduct extends, it is nearly half • mile bswidth. Titheastruet
a ampenaton bridge across this space of sufcient span and,
height to allow of the posse of the large thipeemewould be
a difficult task under any circutesfamer, hut in the case ef
the Albert Viaduct almost impossible, from the fact that there
was no place to attach the suspension chaise, and that the
nature of the ground rendered it necessary that the valley
should be moseed by a level bridge one hundred feet been the
water. The railway ait emerges from the summisa of the
hills on either side of the valley is supported at the water's
edge on 17 double solid 'toes columns 11 feet square, and
varying in height with the slope of the ground, ham
20 to upwards of 100 feet. The whole width of the rives,
(910 feet) is spanned by two arches resting at one point only
in the centre of the stream on four massive cast iron columns.
To render these =alive suspension arches as it were self-
supporting, Mr. Brunel had recourse to a most ingenious
expedient. On each aide of the central pier the roadway is
supported by massive rittspension chaise, which ae in all
suspension bridges form a curve towards the centre. Etch
of these series of chains is tutored to and supported by
a massive wrought iron tube which arching upwards forms
• kind of metal bow, of which the roadway and chaine would
represent the string. Any strain upon the chains and-road-
way would of course hays a tendency still further to. melt
the wrought iron tube., but this is effectually counteracted
by every portico of the chains, the roadway and the arched.
tube being firmly fastened together with wrought iren ties.
Thus each span of the arch forms a rigid and self-supporting
wrought iron girder, the weight of which is borne
equally by the stone columns on the banks of the
dream, and the cast iron pier in the metre. In
forming a foundation for the side piers, Mr. Brunel had but
littledifficulty, ae the solid rock is everywhere on the beaks
of the river close to the surface; but in order to procure &firm
basis on which to erect the Awe and iron pier in the centre of
the river, he had to overcome many serious difficulties. The
wider was 70 feet deep, and below it lay • stratum of
mud andgraved of 20 test thickness. To est ,blish the foes-
dalkm by toms of a common coffer dam would be 9f course
impossible, bat the difficulty was overcome by a novel emb-
odies of the coffer dam principle. An Immense wro t-
iros cylinder, 37 feet in diameter, 100 feet high, and w
no km then 300 tors, was sunk exactly to the centre of
the stream. From this the wieer was pumped out and air
forced in until the men were enabled to work in comparative
dryness at the bottom of the river in a kind of gigantic
diving bell. By this means the whole of the seed and gravel
was removed, the rock levelled, end the solid (slums of
masonry reared from It to above the high-water line.
The two gigantic wrought-iron tube* were pat together on
the river bank, and afterwards floated to their places, and
then raised as one piece. These are constructed of wrought-
iron holler plates ; they are 12 feet high by 17 feet wide, and
are each 470 feet long;
_eeeh span with its chain nod ties
weighs upwards of 1,200 tome. Before these tubes were
their elevated poetions, each was tested with a
placed in
deadweight strain of upwards of 1,200 tons uniformly dietri.
bated over the whole arch. The total deflection did not ex-
ceed seven inches, sad even that deflection quietly recovered
Waif after the weight was removed. The &rape and elevat-
leg of these ponderous tubes were effectd by much the same
mean as those of the Britannia Tubular Bridge. Missive iron
pontoons were used to Beat them to their proper station',
end they were afterwards gradually raised by hydraulic
meatier. This operation was peckipe one of the meet tedious
comeacied with the works. Twice every week the whole
spans were raised 3 feet in one day, and in the inter-
vals the solid nessetrywas built up to it. The ends which
rest upon the cast-bon columns in the middle of the river
could not be secured in this way, as the iron work was cast
in 14 fest joints, thus one end of each of the tubes had to
be blocked up for a week together, until a sufficient interval
was obtained to allow of the internee of one of thejoints.
When the tubes were raised to the requisite elevation the
suspension chains were attached to them, and the roadway was
quickly conairucied. Every portion of the sh ucture is firmly
bound together with croesties of wrought iron, so as to render
it impossible for any portion to move front its place with-
eel the whole structure bang overturned. The total length
of the bridge, from side to side of the valley. is
2,240 bee, 800 feet longer than the Britannia Tubular
bridge. The greatest width of the basement of the anted
I support le only 30 feet, and the greatest height from the foun-
dation to the summit is 280 feet. The quantity of iron used
la the bridge is in all about 3,860 tons, 2,610 tons of wrought
Iron and I,MO tons of cost iron. In the structure no lees
than 14,000 cubic feet of timber were used, and in the con-
Memnon of the piers and stone columns no less than
469,000 cubic feet of motway. To all who have visited Ply-
mouth, the beautiful emery of the Tamar is well known.
The viaduct does not prejudicially affect the view of the sur-
rounding scenery. The architectural features of
the viaduct, it they may be so called, an
tasteful and elegant ; but that they are so is
more the mutt of accident than design, fri there
is not a ringle square foot that is not made subservient
to the strength and stability of the structure. When the
whole bridge was finished it was delivered into the bands of
the government inspector, for the purpose of being officially
tested, previous to the opening of the line to the public.
The of ixtminatioa took piece on Saturday last, in the
of the engineer of the bridge. The tear cousis'ed
Cirsalas g and reposing across the bridge at various spesde •
train weird:dog 400 tons. The greatest deflection which was
observed did nut exceed one inch and a half, and oonsiquently
everything was reported secure.

UNIVERSITY COLLEGE, LONDON.—At a meeting of
prof/mon and stodenut of the fatuity of medicine, halo on
Monday, Professor Williamson Dervin the char, the result
of the crass examinations et the close of the winter term was
announced se follows: Chemiteray_—Gold medal, C. Hough-
ton Gill; fleet giver, Thomas W. Hogg; second silver. J.
N. Miller; certificates, 4th, Themes Ortfiltha ; 6th, equal,
'Lionel Varicas and J. Talfourd Low; 6th, Frederick
Gorge; 7th, equal, A'exender Bruce end A. De Negri.
Birkbeck Laboratory Students—Guld model, Michael Carty;
Lt silver, James R. Maim=• second wirer, William D.
Hewitt; certificates, 4tls, William L. Carpenter; 6th, Jamas
Sharpies; 6th, equal, John 11. Ufford and Gem ge B. Ro-
-1 yer,, equal, W. F. Bickford and Thomas Kelley.
Anatomy—Senior Clem : Geld medal, Samuel J. (lie; let
silver, Isidore D. Lyon ; 2nd silver, Henry C. Bub= ; cer-
tificate*, 4th, Edmund Holland ; sth, Wm. John Hunt ; 6th
John Wisdom Bernard 7th, Henry C. Tolls. Junior elms:
Silver medal, John H. Hutchinson; certificates, 2nd, Thomas
8. Smith; Srd, Fredk. T. Roberts; 4th, Thomas Wm. Bagg ;
6th, M. Oscar Hurlston ; 6:11, Edmund C. King ,• 7th,
Thomas Griffiths; fith, Samuel Coley. Anaetway and Pli
ology Gold medal, Henry Finch; Ist silver, by. C. Bea-
Van • 2nd silver, John P. Baker. Certifieites C
, 4th, equal,:
John Dastan and Wm. John Hunt. Comparative Anatomy :
Gold medal, Henry C. Bastian. Certierates, 2nd, Samna
Home Adams; Brd, Thomas Wilson; 4th, fibeldon D.
Driver. Surgery : Gold Medal, Thee. Charier Kraby• lot
silver John Cilestin Bernard; 2nd silver, Samuel BLitt.
Certificates, Ith, Richard M. Miller; 6th. Vincent Whit-
rearm Medicine: Gold medal, Fiends Wm. Mum; let
silver, equal, Philip Bydnej Jones at.d Win. Money. Certi-
ficate, Jaen B. Arthur Le Diant.
ROYAL INSTITUTION OF GREAT BRITAIN.—At the
annual meeting, bald on Monday, Mr. William role, M.A..
F.H.8., trerauter and viceimeeident, in the choir„ the en-
wool report of the commitice of visitors wain ad and adopted.
The etarament of some received thorn a steady end gradual
increase is the ) early income. Tile tangent of annual con-
tributions of members end subscribers in 1868 amounted to
2,1091.9 t-., being mote than bed been ten ived in any previous
year: the renal pts from serarceittions to lectures were
7391. 14s. 6d. The total ennual income amounted to
6,060/. So. Bd. On December 31, 1858, the funded property
was 25,8311. la Bd. ; end the Wove 9271., with mu Ex-
chequer Bills of 100/. tack. These Ira* no liabilities. A
list of books promoted aocompeules the report,
eithm?totiii
tee year.
ritilM4lo.
Thaa(lati-
in number to 132 VOIUMCO', wahine, with thole apt=
rte
committees of managers and vi.itors, and to Professor Fara-
day, for their seavices to the inititutioa daring the pest yew.
ebwiyuerdthei":o2.4tPelitliao9"l"keleaFca.dd'l'didP:ntWito, patrons.
treasonr, and sooretary, to the
The officers for the ensuing year were elected, the pre-
sident being the Bake of Northumb.:ll4M., K.G., F.R.B. ;
trraourer, Wr. Wm. Pyle. Illtietary• Rev.
John Barlow, We, F.U.S.