The Schoinos was probably common to Egypt and to Chaldæa. The Chaldæans venerated the numbers 6, 60, 600, &c., and their sexagesimal scale, making the year 6 × 60 + 5 days and the circle 6 × 60 degrees each of 60 minutes, has prevailed. The Olympic or Egyptian-Greek measures of distance were on this scale, though land-measures were, officially at least, on a decimal scale.
| 6 Olympic feet | = 1 fathom (orgyia) |
| 60 „ „ | = 1 rod (kalamos) |
| 60 rods or 600 feet | = 1 stadion |
| 60 stadia (6 meridian miles) | = 1 schoinos |
| 60 schoinoi | = 6 meridian degrees |
| 60 × 6 degrees | = circumference of the globe. |
Between the Stadion and the Schoinos there is a long gap, but the Greeks, for whose small country the Stadion was a convenient unit, used, when abroad, the Persian Parasang of 3 meridian miles, = 1/7200 of the meridian circumference.
The rise of other cubits obscured the Olympic series of measures. The Schoinos became absorbed in the Parasang, and under the Roman domination it became a measure of 32 stadia or 4 Roman miles. The Stadion also came to vary; it was nearly always of 100 fathoms, but these might be fathoms of systems varying from the Olympic. The slightly different term Schoinion, meaning a rope or chain, was applied to a measure of 10 fathoms.
The Roman Mile
The Romans took for their itinerary unit a length of 8 Olympic stadia and, dividing it into 1000 paces or double steps, called it a mille (mille passus) or mile. The Roman mile and pace are therefore respectively four-fifths of the meridian mile and the Olympic fathom—
8/10 of 6080 ft. = 4864 ft. = 1621-1/3 yards.
The pace was divided into 5 feet.
1/5 of 4·864 ft. (or 58·368 inches) = 11·673 inches.
There was in course of time some slight variation in the length of the Roman foot. It has been calculated at between 11·65 and 11·67 inches. The best value appears to be that of Greaves at 11·664 inches, but 11·67 seems to me sufficiently accurate, and corresponding better to other Roman measures.