Switzerland has been measuring in metres and weighing in kilograms for exactly 150 years. On May 20, 1875, Switzerland signed ...

NARRATOR: The metric system is a way of measuring things. So with length, the metric measurements are millimetres, centimetres, metres and kilometres. A stamp, would be measured in millimetres.

Units of one measure, such as length, increased by powers of ten (millimeters ... but a system of standards. It survives today as the metric system.

But the world's measurements were, frankly, a mess. France had introduced the metric system during its revolutionary years, but other nations were slow—or outright unwilling—to adopt it.

The U.S. Department of Transportation is proposing to convert the kilometer-based signage along Interstate 19 to the standard U.S. system of miles, drawing criticism from the Green Valley community.

That’s because I-19 is the only American highway that fully measures distance in kilometers, a relic of a failed effort in the 1970s for the U.S. to adopt the metric system. Some 50 years later ...