Primary Body-Based Measurement Units:
1. Cubit – Length from the elbow to the tip of the middle finger (approx. 45–50 cm) / Used in ancient Egypt and Mesopotamia, including in pyramid construction.
2. Foot – Length of an adult male’s foot (approx. 30 cm) / The origin of the modern “foot” measurement.
3. Inch – Width of a thumb (approx. 2.54 cm) / In medieval Europe, it was defined as the width of the first joint of the thumb
4. Hand – Width of the palm (approx. 10 cm) / Still used to measure horse height (1 hand = 4 inches).
5. Yard – Length from the nose to the tip of the middle finger (approx. 90 cm) / Said to be based on King Henry I of England’s arm length.
6. Fathom – Length of outstretched arms (approx. 1.8 m) / Used for measuring sea depth.
7. Span – Distance between the thumb and little finger when fully extended (approx. 20–23 cm) / An ancient unit based on hand measurements.
8. Sun – Approx. 3.03 cm / A traditional Japanese unit, 1/10 of a shaku.
9. Shaku – Approx. 30.3 cm / The standard unit in Japan, used in architecture and kimono measurements.
10. Jō – Approx. 3.03 m / 1 jō = 10 shaku, traditionally used for measuring large structures and fabric lengths in Japan.
Collaborators:
TERAO Koji, Ren