The length of the meridian mile, 1000 Olympic fathoms = 4000 Olympic feet, was divided by the Greek geometers (and probably by the Egyptians and Chaldæans long before them) into 10 stadia, each of 100 fathoms = 600 Olympic feet = 608 feet, which is about our present cable length. And the meridian or nautical mile, used by seamen of all nations, is this same Egypto-Greek mile of 6080 feet = 2026-2/3 yards = 1013-1/3 fathoms = 1·1515 statute miles. It is sometimes put at 6082-2/3 feet. French geometers estimate it at 1852·227 metres = 6076-3/4 feet, one ten-millionth of the quarter-meridian being = 1·0002 metre. The nautical mile is sometimes called a knot, in the sense of a ship going so many nautical miles in an hour, as ascertained by the number of knots of the log-line, each 1/120 of a nautical mile or 50-2/3 feet, run out in half a minute, 1/120 of an hour. The meridian mile must not be confounded with the geographical or equatorial mile, 1/60 degree along the equatorial circumference = 6087-1/3 feet. _Greek Itinerary Measures_ Though a length of 10 stadia is a meridian mile, neither the Egyptians nor the Greeks appear to have used this mile as an itinerary measure. Herodotus says: All men who are short of land measure it by Fathoms; but those who are less short of it, by Stadia; and those who have much, by Parasangs; and such as have a very great extent, by Schoinoi. Now a Parasang is equal to 30 stadia, and each Schoinos, which is an Egyptian measure, is equal to 60 stadia. The Parasang of 30 stadia was then 3 meridian miles, the modern marine league, 1/20 of a degree. 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.