Sorta. The stade was based on the pous which varied. But not that much, and in ways that are often consistently documented. Around the time Eratosthenes was alive, give or take a couple hundred years, it was documented that 1 Roman mile = 8 stades, which gives us something to go of off. While there are other possible definitions, we do have one that we know is probably closest to whatever Eratosthenes used. Using that definition, he had a 15% error. Depending on how you define the stadia, the error can go as high as 30%. I’m still impressed he got within the right power of ten with nothing but a stick.
Comment on Sticks
KillingTimeItself@lemmy.dbzer0.com 8 months ago
isnt this the fucker who used units of stadia? The unit that we have no historical reference to? (at least one significant enough to be certain about it’s actual referenced distance) Which means that we don’t actually know how accurate it was?
crispyflagstones@sh.itjust.works 8 months ago
KillingTimeItself@lemmy.dbzer0.com 8 months ago
+/-20% error isn’t terrible on a conversion. The fact that it’s only 10% offset is crazy though.
olutukko@lemmy.world 8 months ago
I mean we do know the formula, se we know pretty well how accurate it was.
"The simplified method works by considering two cities along the same meridian and measuring both the distance between them and the difference in angles of the shadows cast by the sun on a vertical rod (a gnomon) in each city at noon on the summer solstice. The two cities used were Alexandria and Syene (modern Aswan), and the distance between the cities was measured by professional bematists.[16] A geometric calculation reveals that the circumference of the Earth is the distance between the two cities divided by the difference in shadow angles expressed as a fraction of one turn. "