I was just watching a documentary about feudal Japan, and in particular the period of the rise of the Tokugawa shogunate. There was a quote “…estimated the distance to be 2 1/2 miles.”
Clearly a mile is a western european measurement - what units of measurement did the Japanese use between say 1000AD-1850AD?
http://www.convert-me.com/en/convert/length
They are all there. Thai measurements too, if you are so inclined.
The old Japanese system of measurement is centered around the shaku. A shaku was defined as the distance between the outstretched thumb and the tip of the middle finger. One ho (step) is defined as 5 shaku. The largest unit, the ri (from the Chinese li unit) corresponds to 300 ho, or 5 chô, which means that one chô = 60 ho = 300 shaku.
Unfortunately, ho was also sometimes defined as 6 shaku, and the ri as 6 chô, which complicates things a bit.
The above system was decided in 701, by emperor Monmu as part of a very large and important plan to standardize government practices.
The system was last modified in 1891 and the units were redefined against the metric system. 11 ri was now equal to 43.2 km. (Where they got that value, I don’t know.) That gives 1 ri = 3.93 km. By that time, the definition of chô had changed a bit so that there were 36 chô in 1 ri and 360 shaku in 1 chô, hence the values returned by Mr. Babbington’s site.
The other units are defined as follows:
1 jô = 10 shaku
1 ken = 6 shaku
1 sun = 0.1 shaku
1 bu = 0.1 sun = 0.01 shaku
Incidently, 2.5 miles is about 1 ri, using the 1891 convention. That might not be a coincidence. If you do the math, however, you’ll see that in 701, one ri was worth only about a fourth this distance.
Or “a quarter” as we call it nowadays. 
:o
Been thinking too much about music theory lately.
I assumed something of the sort… You’re not the typo type.
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Speaking of Feudal Japan, did anyone see the new Takeshi Kitano “Zatoichi” movie? Absolutely brilliant…
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I’m not? Oh, believe me wehn I say I veru much am.
Alas! When I finally made up my mind to go see it, it wasn’t playing anymore.