|
|
|
|
|
|
The barleycorn is a small English unit of length equal to 1⁄3 of an inch (i.e., close to 0.8467 cm) still used in Great Britain and Ireland as a determiner of shoe sizes.
The light-day is a unit of length useful in astronomy, telecommunications and relativistic physics. It is defined as the distance that light travels in free space in oneday, and is equal to exactly 2.59020683712×1013 metres.