[00:01.080]--- lesson 17 The longest suspension bridge in the world
[00:07.320]--- Listen to the tape then answer the question below.
[00:12.920]--- How is the bridge supported?
[00:17.520]Verrazano, an Italian about whom little is known, sailed into New York Harbour in 1524 and named it Angouleme.
[00:28.640]He described it as 'a very agreeable situation located within two small hills in the midst of which flowed a great river.'
[00:37.560]Though Verrazano is by no means considered to be a great explorer, his name will probably remain immortal,
[00:45.680]for on November 21st, 1964, the longest suspension bridge in the world was named after him.
[00:54.280]The Verrazano Bridge, which was designed by Othmar Ammann, joins Brooklyn to Staten Island.
[01:02.400]It has a span of 4,260 feet.
[01:06.880]The bridge is so long that the shape of the earth had to be taken into account by its designer.
[01:13.880]Two great towers support four huge cables.
[01:18.320]The towers are built on immense underwater platforms made of steel and concrete.
[01:24.520]The platforms extend to a depth of over 100 feet under the sea.
[01:29.720]These alone took sixteen months to build.
[01:33.520]Above the surface of the water, the towers rise to a height of nearly 700 feet.
[01:40.000]They support the cables from which the bridge has been suspended.
[01:44.720]Each of the four cables contains 26,108 lengths of wire.
[01:51.760]It has been estimated that if the bridge were packed with cars, it would still only be carrying a third of its total capacity.
[02:00.120]However, size and strength are not the only important things about this bridge.
[02:06.520]Despite its immensity, it is both simple and elegant,
[02:10.840]fulfilling its designer's dream to create 'an enormous object drawn as faintly as possible'.