The Metre and the Moon were connected by someone in revolutionary France. Here we show how the numbers tell the story behind the creation of a unit that was designed to replace all of the ancient measures. It shows how a knowledge of metrology can revolutionise our knowledge of the past and reveal hidden secrets within artifacts and buildings.
In ancient metrology all of the units of length, and there were many, divided into each other through the use of only the first five prime numbers, 2, 3, 5, 7, and 11. They may not divide perfectly but only these primes will remain in any fractions of a foot after a division of one into another.
It is quite a surprise therefore that the Metre, a recent measure emanating from the time of the French Revolution, upsetting of the ancien regime, is commensurate with the English foot at all. The surprise comes from the fact that the Metre was created from a measurement of degrees of latitude and an estimate of the quadrant from Equator to Pole - the metre being defined as one ten millionth of the length of that quadrant. Since the measurements had significant errors, the final value was frozen at an incorrect value. So why should it, like an ancient measure, divide into the foot at all?
