"A true hereditary and traditional measure is something almost as vital as a language, sometimes more so; and to stamp it out utterly and instantly is not within the province, or the power, of any government of men for the time being.”
Charles Piazzi Smyth
How John Michell first established certain rules that governed ancient metrology
John Michell (9 February 1933 – 24 April 2009) the great philosopher-antiquarian was the first man to establish definite values for units of measurement. Prior to this, due to variations in linear measurement, virtually any close value could be proposed as an intended module. Through many comparisons of recorded modules he stated that examples were found in Roman, “Polar” feet, Greek, royal Egyptian and Ancient Jewish that all existed in two distinct variants that related as 175 parts to 176. This inferred that the modules of these different nations all referenced an earlier canon, which in turn implies an earlier and now forgotten culture that had been universal.
These are the exactly expressed modules given in English feet:
The two variants are under the headings “Tropical” and “Northern” because it was believed at that time that it was the variations in the length of the geographic meridian degree at 10º latitude and latitude 51º that dictated the lengths. These variants enabled him to calculate two specific earth radii from the “sacred” cubit of the Jews, that of 20,854,491ft for the polar radius and 20,901,888ft as the mean radius of the earth and that these radii differed as 440 to 441.
Having these exactly expressed values enabled the foundation of the more complex structure of ancient metrology to be understood because these data points were now in place. Firstly it was realized that that the fraction 175 to 176 was also the difference between the anciently used pi ratios of 25/8 (or 3.125) and 22/7 (or 3.142857), thus establishing a purely mathematical as well as the geographic explanation as to its presence in metrological values. Another focusing was the observation that the values of the “polar” feet at six parts to seven of the royal Egyptian, were in fact the universally known common Egyptian feet.
Also pertinent to the structure was the recognition that the term “sacred Jewish” feet were far too long to be termed “feet” – they were arrived at through the division of the sacred cubit by 1 ½, when in point of fact the sacred Jewish cubit is a two feet cubit. Two important factors were brought to the fore when the correction was made. Firstly take the value 2.0736ft as the sacred cubit, this divided by two is 1.0368ft, it is therefore a two-feet cubit of the common Greek foot. Furthermore, if the value 1.3824ft is divided by 1½ it is .9216ft and this is a value of the pie or Spanish foot, one third of the vara; it is an Iberian 1½ feet cubit. Thus was revealed an exact integration of metrological values of far greater complexity than John had first proposed that goes much further than merely two variants, or this limited number of foot modules.
Just this small exercise is a perfect illustration of the total amalgamation of metrological values that underscores the point that it is a singular system. The sacred Jewish is common Greek and relates to Iberian as 9 to 8; the common Greek is 21 to 20 of the common Egyptian and 9 to 10 of the royal; the Iberian is 14 to 15 of the common Egyptian and 4 to 5 of the royal. In this fashion, all of the foot values of the world so interrelate– by unit fractions. Having knowledge of this connectedness and more that one value to maintain accuracy (by comparisons) it enables any module to be identified and classified.