The United States is one of only a handful of countries that doesn't use the metric system. Most of the world calculates distances in meters. The creation of the meter in 1792 was based on the need to agree on a uniform system of measurement. But the first time scientists tried to determine the length of a meter, they made some mistakes. Listen to this public radio story to learn why accuracy is necessary.
Story Length: 4:38
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AIR DATE: 06/23/2014