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In the mid 19 centuries, suspension bridges were collapsing all across Europe. Their industrial cable f-- during turbulent weather and -- under the weight of their decks. So when a German American engineer named John Roebling proposed building the largest and most expensive suspension bridge ever conceive? over New York East River. City officials were under? skeptical.But Manhattan is increasingly overcrowded. And commuters from Brooklin crowded the river. In February of 1867, the government approved roebling's proposal. To avoid the failures of European bridges, Roebling designed a high-b? bridge model, from suspension bridges, he incorporated large cables supported by

central pillars and anchored at each bank. This design is ideal for supporting long dex? which hang small vertical cables but roebling's model also drew? from sta? bridges. These shorter structures helped? diagonal cables that run directly to support towers. By adding these additional cables, roebling improved the bridge's stability while also reducing the weight on its anchor cable.

Similar designs has been used some other bridges, but the scope of roebling's plant year dwl? them all. His new bridge decks spend over 480m 1.5 times than any previous built suspension bridges.