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The Meter Redefined

On October 21, 1983, the General Conference on Weights and Measures redefined the meter, making it the distance light travels in a vacuum in 1/299,792,458 of a second. Since the 17th century, many ways of measuring a meter have been proposed throughout the world. After the French Revolution, there was a push to institute new measurements to replace the ones associated with the ancien régime. Along with changes to weights and money, the meter was introduced in France to much consternation from French citizens. Throughout its life, the meter has been defined based on gravity, meridians, metal bars, and wavelengths of radiation from Krypton 86. The definition established by the 17th General Conference on Weights and Measures is still the definition of a meter used throughout the world today. 

 

Items in Our Collection:

The Metric System by Judson C Welliver; University of Virginia. Library. Electronic Text Center. 

 The international (SI) metric system and how it works by Robert A Hopkins

 Standard for use of the International System of Units (SI) : the modern metric system by American Society for Testing and Materials.; Institute of Electrical and Electronics Engineers.; American National Standards Institute.