Early Units of Measurement and the Nautical Mile

Extract

To find out the origins of the nautical mile it is necessary to go back to early times, for, like so many other things, it did not spring up in full bloom in a day, but evolved by slow degrees.

Early man, seeking units of measurement, logically looked about him for something in nature that he might use as a standard. For very short distances he used the width of his finger, the width of his hand, his span, the length of his foot, or the length of his forearm. As these varied between men, so the length of the derived units varied. The foot, for instance, varied from 11 to 14 inches. Even greater variation occurred in the length of the cubit, which originally was taken as the length of the forearm, from the elbow to the end of the middle finger. This unit was widely used, but varied from country to country, and was not even constant within various parts of the same country in some instances.