The length of the Ancient Minoan foot and the Ancient Japanese Shaku are nearly identical This post is in response to questions posed on similarity between the Minoan foot and the the Japanese shaku


These Ancient standards of measurement are, in all probability closely related. At first glance the standards seem to differ by 0.6 mm out of 303 but on further examination they are much closer and in fact could be considered identical.

The Ancient Sumerians in the third millennia BC created a system of measurements which was based on a one second pendulum which was almost one meter long. Distance was measured in multiples of this standard. One of these  was a little longer than 1/6 of a nautical mile while the next was about 5 nautical miles. The accuracy of these standards was improved throughout  the following centuries

The Minoan foot was derived precisely from the length of a pendulum which swings 366 times in the period the earth rotates 1/366 of its circumference measured on a line of sight to Venus in opposition. The length of this pendulum is doubled then multiplied by 366 to produce a length which is approximately 1/6 arc minute in latitude. The Minoan foot is 1/1000 this distance.

In a similar manner, using the same formula and taking into account the difference in gravity at the two locations as well as allowing for the properties of a real pendulum, the error is well within the measuring ability of these ancient civilizations.

There can be no question that both of these standards are part of the same attempt to replicate a length equal to 1/6 of today’s nautical mile. A standard for accuracy which was only surpassed by the Greeks foot and Stadia.

Today, the arc second and the arc minute (nautical mile) are shown on every chart used today for navigation on both the sea and in the air. Maybe its not so surprising  that sea faring nations half a world apart used the same navigational standards so long ago.

1 Why this is important

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  1. March 14, 2012 This may not seem important to the layman but to a navigator it meant that 360 of these basic units of length was one degree and 360 degrees was all the way around the world on a meridian through Japan. Taking a trip on this meridian would take us southward through Australia and Antarctica, then northward though Brazil, the Atlantic Ocean, Canada, Iceland the north pole then southward through Siberia and back to Japan. The length of this journey taken over 3000 years ago would have been 99 percent of what we know the true distance to be today. We know that the Polar circumference of the Earth was important to the Japanese because one of their standards thr Ri is 1/10,000 the polar circumference I would like to thank Gretchen Leonhardt in her website “Kanashi” for bringing this ancient Japanese measurement to the attention of scholars throughout the world.