Before standardization, units of measurement were often manipulated by tyrants to cheat peasants and steal land.

This week, Sam Kean takes a look at some ridiculously precise standards -- the meter, the second, and other international standard units -- and the role that elements have played in defining ...

Unfortunately, scientists botched the measurement, and the length of the meter that came into common use was later found to be 0.2 mm off the supposed definition, an intolerable gap.