worked though. The train's total dead weight was simply added to the bridge, and if it did not hold, it was said to be structurally unstable. Lindenthal's idea of not having to carry the full load allowed bridge designers to create bridges that were still stable, but at the same time much lighter and cheaper. Gustav Lindenthal made bridges that reached new heights for his time. At the time of Hell Gate's completion, it stood as the longest and heaviest steel bridge in the world. Gustav Lindenthal also expanded the idea of "double decker" lanes on his bridges. The Queensboro Bridge is one of the bridges Lindenthal designed that displays the double decker idea. Construction techniques During the time Lindenthal practiced engineering, the railroad industry was expanding and replacing many wooden-truss bridges with stronger ones capable of handling the heavier locomotive loads. In order to accommodate these heavier trains, different construction materials were being utilized. The materials being considered by engineers like Lindenthal were reinforced concrete, cable, and steel. Steel and reinforced concrete were two main materials used in the truss bridges Lindenthal designed. The use of reinforced concrete was a relatively new idea in bridge construction, with its first use in 1889. The design of the Hell Gate Bridge required a different approach to bridge construction. Nearly all major members of Hell Gate are composed of smaller trusses. The erection of the Hell Gate was carried through without the assistance of any falsework, or work that was not part of the actual bridge. This was accomplished by building the two halves of the arch simultaneously from each tower. The steel work was supported with the use of cables during construction to carry the load of the arches until they finally met at the center of the span. In another instance, a bridge needed to be constructed over the Monongahela River, after the ferry, which was used for many years beforehand, became outdated. The first bridge, designed by John Roebling, continuously swayed and deflected, and was being "shaky and loose." Lindenthal was given an opportunity to design a replacement, the Smithfield Street Bridge in Pittsburgh. This bridge, completed in 1883 using the structural form of a lenticular truss, could withstand higher stresses, as well as using resources that made it more economical (Approximately $23,000 was saved simply by using these materials). "Lindenthal's use of steel instead of iron wherever possible