First US wire suspension bridgeIn 1842, the first U.S. wire suspension vehicle bridge was opened to traffic at Fairmount, Pennsylvania, for Calloway Sreet to cross the Schuylkill river. It was designed and built by the engineer Charles Ellet to replace the 1816 wooden “Colossus” bridge that burned in 1838. Ellet’s bridge spanned 342 feet, and had a clear width of 25 feet. It was replaced in 1875 by a truss bridge. From 1809 to 1816 there had been prior short-lived bridges at the site, each of which collapsed under excessive loads. One used suspension cables of long iron links (1809-1811), replaced by another suspension (fell 17 Jan 1816) and a third (opened Jun 1816, fell Winter 1816) was only 18 inches wide, but was the first to use cables, made with six 3/8" wires by the nearby wire mill of White and Hazard.« |
