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--- lesson 17 The longest suspension bridge in the world |
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--- Listen to the tape then answer the question below. |
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--- How is the bridge supported? |
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Verrazano, an Italian about whom little is known, sailed into New York Harbour in 1524 and named it Angouleme. |
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He described it as 'a very agreeable situation located within two small hills in the midst of which flowed a great river.' |
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Though Verrazano is by no means considered to be a great explorer, his name will probably remain immortal, |
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for on November 21st, 1964, the longest suspension bridge in the world was named after him. |
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The Verrazano Bridge, which was designed by Othmar Ammann, joins Brooklyn to Staten Island. |
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It has a span of 4,260 feet. |
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The bridge is so long that the shape of the earth had to be taken into account by its designer. |
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Two great towers support four huge cables. |
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The towers are built on immense underwater platforms made of steel and concrete. |
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The platforms extend to a depth of over 100 feet under the sea. |
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These alone took sixteen months to build. |
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Above the surface of the water, the towers rise to a height of nearly 700 feet. |
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They support the cables from which the bridge has been suspended. |
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Each of the four cables contains 26,108 lengths of wire. |
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It has been estimated that if the bridge were packed with cars, it would still only be carrying a third of its total capacity. |
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However, size and strength are not the only important things about this bridge. |
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Despite its immensity, it is both simple and elegant, |
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fulfilling its designer's dream to create 'an enormous object drawn as faintly as possible'. |