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發表於 2013-12-2 03:59:27
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The Brooklyn Bridge
Issued in 1983
In l869, actual construction of the Brooklyn Bridge, over the East River between Brooklyn and Manhattan, started. John Augustus Roebling, original architect of the project, was injured in an accident. Blood poisoning resulted in his untimely death. Fortunately his son, Colonel Washington Augustus Roebling, took over direction of the work involved from then on until completion. The grand opening was in May 1883.
This great bridge handles two elevated railroad tracks, two streetcar (trolley) tracks, road lanes for vehicles, and even a foot walk for pedestrians. Just to observe the massive stone towers one is in awe of their height. They had to be lofty to carry the cables which in themselves-wire by wire-measured 16 inches in diameter. Tons of steel wire had to be used to hold up the incredibly heavy bridge deck.
With the long main span, and two shorter spans, the bridge is 1 mile long. It is constructed of four cables, each anchored to plates of many tons, embedded in masonry foundations. Each foundation has a weight of 44 thousand tons. Every cable contains more than five thousand steel wires-a total of fourteen thousand miles of wire. It took thirteen years to build the bridge. At present thousands cross it each day. Even this writer, when working in New York, walked across this Bridge with friends and couldn't help but marvel at the magnificence of it all. |
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