On July 26, 1820, spectators were so eager to stand on Capt. Samuel Brown's first suspension bridge, they broke through barriers to reach the wooden platform. Though the official opening-day ceremony was chaotic, it was clear Brown's design was a success. The 449 ft long span over the River Tweed connects Horn-cliffe in Northumberland, England, to Fishwick in Berwickshire, Scotland. It would become the world's oldest vehicle suspension bridge. Brown, an Englishman, had been serving in the Royal Navy for nearly 12 years before he was given the chance to change a key aspect of how ships functioned. At the time, all rigging and anchoring cables were made of hemp, a material that snapped, eroded, and emerged from the ocean slimy and foul smelling, notes John Harland in The Transition from Hemp to Chain Cable: Innovations and Innovators. By the end of the 18th century, however, wrought iron was improving in quality and dropping in cost. Iron chain cables were more durable, and Brown realized that they were an easier-to-maintain alternative to the fiber cords he and his shipmates once struggled with.
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