Yes, it's from a book called "Uncle John's Bathroom Reader" and that book was resting on a closed toilet seat in a nation that only kind of uses the metric system in certain situations... however, you'd be surprised how much you can learn after a single visit to any local fast-food joint!

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[–] 7 points 15 hours ago (2 children)

And the fact that Inch is not precisly defined. "Three grains of ..." or "King's thumb" is not a precise definition.

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  • [–] 1 point 1 hour ago

    Precise definition isn't really practically necessary. It's only useful if you need to independently recreate a system in isolation. It's much easier to have a reference material and just copy it. You can even build a reference length if you have something with known measurements.

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