The dawn of modern navigation: time for an empire. (marine chronometer inventor John Harrison) The Economist (US) | December 26, 1992 | COPYRIGHT 1992 Economist Newspaper Ltd. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan.  All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information) Copyright

IN 1707 an entire British fleet sailed homeward from Gibraltar on to the rocks of the Scilly Isles, with the loss of 2,000 lives. This great naval tragedy happened because the admiral, Sir Cloudesley Shovel, had no idea where he was. For 60 more years, sailors would have to sail as blindly as he. They could find their latitude: the angle of the pole-star above the horizon gave them the answer. But they could not find their longitude because stars swing continually from east to west across the sky, telling them the local time but not their position. To discover longitude from ...

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