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Comment by lom | Hacker News Reader

Why is it called the international survey foot if it’s just used in the US as well?

I think NIST has a better explanation of the history: https://www.nist.gov/pml/us-surveyfoot

But basically, the "international foot" IS the foot. It's the foot you use everywhere, except in US surveying. Calling it the "international" foot in a sense is just picking an arbitrary way to explicitly disambiguate against "US survey foot".

Infuriating that we still use the foot but it is legally defined based on the meter!

The US foot has always been defined by the meter. Originally, Thomas Jefferson set the foot to be exactly .3 meter. The science of surveying and measurement weren't great in the late 18th and early 19th c, so the definition of the meter changed; by then, the US surveys were too far along to change.

My family has been involved with surveying on-and-off for ~100 years. I hated grabbing measuring tapes as a kid, because the "foot" or the "inch" was always sone batshit crazy thing. Like: decimal foot based on a 30cm foot; the "inch" is 3cm.

No, until shortly before the convention of the meter (1875) the US used imperial prototypes provided by the UK. There was some divergence after the fire in the Palace of Westminster destroyed the originals, and the replacements were not very high quality, wrt the rapidly improving manufacturing tech of the time. I can’t remember if the US got a copy of the mètre des archives during this time, but both the US and UK defined (different) official conversions between metric and imperial / US customary. After the new BIPM prototypes were made in the 1890s, they became the standards for high precision purposes in the US and UK. The imperial / US customary conversion factors reconverged over the next few decades, except for the US survey foot.

That makes more sense, thank you.

Wait until you learn about shrink rules, used in patternmaking!

Cast metal shrinks when it cools and solidifies. To make patternmaking tolerable, shrink rules are scaled up by the shrinkage allowance so that 5" in the pattern doesn't have to be scaled by the patternmaker to some random measurement. Unfortunately, the shrink allowance varies among metals...

A steel framing square also has some completely cursed scales. I'm not a carpenter, and I won't even pretend to know why anyone needs inches graduated into 10ths or 12ths.

Same reason why is it called World Series when only parts of North America compete.

In this case the USA is in the same club as Myanmar and Liberia.

If there is ever a baseball team somewhere else in the world that is remotely similar in quality to top MLB teams, I’ll happily admit that “World Series” is a dumb name. (This would most likely happen in Japan if it happens anywhere). Until then, I’ll continue using it.

The name dates back to the 1800s, when most countries were still on customary measurements (the meter existed at this point, and indeed the "international foot" has been defined in terms of the meter since 1893, but SI was still 70 years away).

Because it was agreed to by six nations in the International Yard and Pound Agreement of 1959.

Oh, just wait until you read ISO 2848, which defines a "metric foot", which is exactly 30 cm, and which is an international norm...

Canada had used it too prior to 1970, and probably some time after as they made the metric switch.

I wish we’d just switch too already.

When we invade other countries we need to survey there. So it is international.

A lot of places do business with the United States.

Consider it an international standard used for working with the United States.

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