The clocks became known as chronometers. By eighteen fifteen, five thousand chronometers were in use on ships sailing the world's oceans. The complex documents and mathematical work were no longer necessary. Almost any sailor could tell what his longitude was by simply looking at a clock. The world had changed.
BOB DOUGHTY: John Harrison's clocks can be seen today at the Old Royal Observatory in Greenwich, England. The first three are still operating, showing the correct time.
To look at them is to see the simple solution to a problem that worried people for many centuries.
Today, the solution to the problem is so common that it is difficult to understand that there was a problem at all.
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STEVE EMBER: This program was written by Oliver Chanler and produced by Paul Thompson. Our studio engineer was Al Alaby. This is Steve Ember.
BOB DOUGHTY: And this is Bob Doughty. Join us again next week for EXPLORATIONS, a program in Special English on the Voice of America.
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2013-11-25
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2013-11-25