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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!
It's so impressively thought out. I got my mind blown when the physics teacher told us that 1 calorie is the amount of energy it takes to heat 1cc by 1°C. Suddenly you realise that someone actually put some effort into this whole system
It’s incredibly funny to me that the two metric units that the US actually commonly uses (calories and Watt-hours), aren’t SI units. Those are both measured with Joules.
The one that blew my mind the most was finding out that calories are calculated by setting the food on fire, and then measuring how much it can heat water. Calories are literally just a measurement of how well something burns.
And iirc 1 Joule is the energy required to lift 100g by 1m
No. It is pushing by 1 metre with a force of 1 newton.
No. It is Newton pushing 1 litre of jewels.
No. It is J. Lo pushing a newt on 1 litre of water.
No. It is Jules Verne pushing a carton of fig newtons a distance of 1 litre.
The paragraph on the meter should mention that their measuring error from the pole to the equator was .02%, which, without using satellites or even electricity, is fucking impressive.
.0002 × 10,000,000 = 2,000 meters
So they were off by 2 kilometers? Not bad, honestly...
I reckon if took every turd I'd ever caused and laid them (both senses) end-to-end it would be more than 2km, for context.
That is impressive & a nice amendment on your part. Thank you for the added detail
So how the hell was it done? Long piece of rope? Hot air balloon? Or having a bird fly from one point to another and timing it?
Calculations. In 240 BCE, Eratosthenes used a stick. He basically found a place where the sun was directly overhead, and measured the shadow from a stick a known distance to the north of that location. He approximated the circumference of the earth to be 25,000 miles, which was off by 99 miles.
I don't think he used miles.
'Kid Named Miles' 
There's a part in one of these Uncle John's Bathroom Readers that has a paragraph about the dude with the shadow stick.
Lots of triangulation and extrapolation
https://en.wikipedia.org/wiki/Arc_measurement_of_Delambre_and_M%C3%A9chain
Love me some uncle john's! Those page numbers are iconic, though I could immediately tell it was UJBR from the asterisks and writing style. Is this from "plunges into history"?
I think this snippet misrepresents the accuracy of the former definition of the metre. Sure, it's no longer the distance from the equator to the pole (the modern definition uses the speed of light and the period of transition for a particular atom), but the difference is quite small. The circumference of the Earth around the poles (so 4 times the distance from equator to pole) is 40007.863 km. In Napoleonic times scientists had a pretty good idea what the shape of the Earth was.
I use centimeters for certain things, but I call them "inches".
And the fact that Inch is not precisly defined. "Three grains of ..." or "King's thumb" is not a precise definition.
One ten millionth of a quarter of the circumference of some random ass planet somewhere isn't either.
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.
Nowadays, the inch is defined in metric units anyway.
Without metric inch is arbitrary unit, can be anything.
Also, unlike the imperialist system it is not utter horseshite.
Love me some Uncle John’s. I’d recognize that page number decorator anywhere!
My god, I commented almost this exact thing, word for word.
Looks at comment history
Oh wow, yeah you did! Great minds think alike, I guess!
Uncle John's bathroom reader! ~~I know this has nothing to do with the metric system, but I saw the toilet paper roll around the page number and got a surge of happy brain sauce due to the happy memories of all the copies I owned through the years: 2~~