Charing CrossThamesLondon, England676.5501845I. K. Brunel.
La Roche BernardVilaineLa Roche Bernard, France650.4501846Leblanc.
UnionTweedGreat Britain449301820Sir S. Brown.
HammersmithThamesLondon, England422.2529.51824Tierney Clarke.
3 spans; 150, 400, 150.ThamesChelsea, England400
ConwayArm of the seaWales32722.331826Telford.
Chain PierBrighton, England255181823Sir S. Brown.
Isle of Bourbon220.325.481823Brunel.
DnieperKieff, Russia7 spans.
Total length, 2,562 feet.
Plate IX., page 519.
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ed by a great tube or hollow beam, through the center of which a roadway or railway passes.
A similar principle — that of the truss-beam — had been applied, varying, of course, in details of construction, to timber bridges, both in Switzerland and America; but the idea of the wrought-iron tubular bridge, and the carrying out of the details of construction which made it a success, are due to Fairbairn, to whom is due the credit of devising the form and proportions of the tubular bridges of Conway and Menai.
The rectangular cellular beam laid on its edge and constructed of wrought and cast iron in their respective places was Fairbairn's, as was also the idea of making it self-supporting.
Stephenson very reluctantly gave up the idea of supporting it by chains.
The most remarkable one ever constructed is that across the Menai Straits, on the Chester and Holyhead line of railway, and which unites the island of Anglesea with the mainland of Wales.
is a general view o