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Or as we Americans, and our friends in Myanmar and Liberia,

How Did The Meter Get Its Length

Three countries in the world do not routinely use the metric canada goose outlet system for making measurements. Those three countries are Liberia, Myanmar and the United States of America. Although to be fair, both Liberia and Myanmar are taking steps to go metric. Canada Goose Jackets Not to say the United States does not make canada goose uk black friday use of the metric system. government definition of a foot is 0.3048 meter. But if the length of the foot is based on the meter, NPR science correspondent https://www.chinese-sharpei.de Joe Palca wondered, what is the canada goose outlet uk length of the meter based on? That’s the latest question he’s posing as part of his series, Joe’s Big Idea.

JOE PALCA, BYLINE: The 18th century is famously known as the Age of Reason. Disorder was upsetting. And over in France, there was plenty of disorder.

PALCA: That’s Northwestern University historian canada goose uk shop of science, Ken Alder. He’s a good person to talk to about how the meter got its length because canada goose outlet online he wrote the book about it, canada goose canada goose outlet outlet toronto factory literally. It’s called “The Measure Of All Things.”

ALDER: Historians have estimated that, within France alone, there were 250,000 different units of measurement in use at the time.

PALCA: So this is a big problem. Alder says there was a simple solution to the problem.

ALDER: canada goose factory sale Which was to take the Parisian measures and expand them to the whole country. But a group of scientists or savant, canada goose outlet shop as they would’ve been called in those days, had a different canada goose outlet new york city idea. And they wanted to base the unit on nature, a unit that would be the same for everybody, because nature was the same for everybody.

PALCA: So the savant did what savant do they argued and debated and discussed canada goose outlet jackets trying to decide what aspect of nature they should use to base their unit of measure canada goose black friday sale on.

ALDER: The proposal that ended up sort of winning the day was a proposal that based the measure on the size of the world itself.

PALCA: A meter would be defined as one 10 millionth of the distance from the North Pole to the equator trouble is, no one knew exactly what was the distance from the canada goose coats North Pole to the equator. So in 1792, an expedition was mounted. Now, going all the way to the Pole and the equator seemed a bit too ambitious, so the idea was to measure the distance between two cities Dunkirk in France and Barcelona in Spain that were on a straight line directly north south of official canada goose outlet one another. By knowing the exact latitude of the cities, the savant could use the distance between them to extrapolate the distance from the Pole to the equator. The job of making the measurements went to two astronomers named canada goose outlet sale Delambre and Mechain. Delambre headed north and Mechain went south.

ALDER: The expedition is originally expected to be done within a year. In the end, it takes them seven.

ALDER: For one thing, war breaks out between Revolutionary France and the rest of Europe. And who are these strange men climbing into high towers and fortifications and churches, peering out into the distance with these strange scientific instruments? And they’re repeatedly goose outlet canada hauled down from these towers, thrown in jail and, at times, threatened with death.

PALCA: Eventually, Mechain and Delambre delivered their results to the savant. The savant spent a year doing calculations. And in the end, they create a bar with the calculated the length.

ALDER: Made out of platinum that will serve as the actual embodiment of that physical standard, the meter.

PALCA: So that’s the story. Well, not quite. Turns out the savants and the surveyors made some errors. And Mechain even secretly redid some of his measurements, got different numbers and didn’t tell anybody. So in the end, that bar of platinum is close to one 10 millionth of the distance from the North Pole to equator. But Alder says scientists now know, it’s short by two tenths of a millimeter. Or as we Americans, and our friends in Myanmar and Liberia, would say around eight thousandths of an inch.

ALDER: And the irony here is that, in a sense, they could have canada goose clearance started out by simply creating a bar and calling it the standard meter. And indeed, some canada goose uk outlet people from the very beginning had suggested really, why was it necessary to go so far to find what lay so near? Why not simply declare, yo, it’s a meter.

ALDER: (Laughing) Yeah, exactly.

PALCA: So even though it isn’t exactly one 10 millionth of the distance from the North Pole to the equator, the length of that bar is what the world first knew as a meter. canada goose black friday sale Joe Palca, NPR news.

INSKEEP: The program that measures up. Its MORNING EDITION from NPR News.

NPR transcripts are created on a rush deadline by Verb8tm, Inc., an NPR contractor, and produced using a proprietary transcription process developed with NPR. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary.

Correction June 23, 2014

Previous versions of this story said a platinum bar cast in the 19th century was what the world used as the official length of a meter. It was the first official standard for the canada goose outlet canada length of the meter. There’s another in effect today.