I think a mile is specified in terms of ‘chains’ not really feet or yards.
Feet and yards are meant for measuring smaller stuff, like the size of a foot, or a courtyard.
The ‘chain’ was a specific surveyors tool for measuring larger land areas. I imagine defined to be a length of physical chain practically manageable by the surveyor - probably pre-dating optical / triangulation methods before lenses got cheap.
I think an acre was then defined as 10 square chains or something.
But go back in time far enough and different jurisdictions have different lengths of standard chain, so different miles and acres derived from it. But it doesn’t really matter because if you were buying land in Scotland, then you’d probably want to use a Scottish surveyor and his big long chain.
The nautical mile is then a whole other kettle of fish.
I think a mile is specified in terms of ‘chains’ not really feet or yards. Feet and yards are meant for measuring smaller stuff, like the size of a foot, or a courtyard.
The ‘chain’ was a specific surveyors tool for measuring larger land areas. I imagine defined to be a length of physical chain practically manageable by the surveyor - probably pre-dating optical / triangulation methods before lenses got cheap.
I think an acre was then defined as 10 square chains or something.
But go back in time far enough and different jurisdictions have different lengths of standard chain, so different miles and acres derived from it. But it doesn’t really matter because if you were buying land in Scotland, then you’d probably want to use a Scottish surveyor and his big long chain.
The nautical mile is then a whole other kettle of fish.