Robert Stephenson (1803-1859) was a civil engineer famous for his locomotive and railway works, however he was also a bridge builder. Here is a piece on his building of the Britannia Bridge over the Menai Straits, connecting the isle of Anglesey with mainland north Wales. Sadly the bridge was destroyed by fire in 1970 and had to be completely rebuilt.
The Britannia Tubular Bridge Across the Menai Straits
Robert Stephenson, so prominently identified with the early history of the locomotive, applied this principle to bridge building.
The Tubular Bridge. A suspension bridge at Conway failed and Stephenson applied to Parliament in  for permission to build a bridge of a new design of which he was the inventor. The permission was secured and in  the Conway Tube bridge was begun. It was made of boiler iron plates four to eight feet long, about two feet wide, and five eighths inch thick, put together and riveted by hand, forming a tube 412 feet long, 14 feet wide, and 25 feet high in the middle. It weighed 1300 tons, gave satisfaction, and is still in use. The Victoria bridge at Montreal was Stephenson’s masterpiece. This is a quadrangular tubular bridge 16 feet by 22 feet in cross section and 1 1/4 miles long. It was completed in  and cost about $7,000,000.
The tubular bridge served its purpose but it is now known that a different arrangement of the metal will give greater strength for the same weight. The amount of material and workmanship required render them the most costly of all structures, and both the Britannia and the Victoria bridge ruined the companies that built them.
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