Convert roman finger to nautical mile

The nautical mile is 1,852 m, defined so that it matches one minute of latitude: a degree of latitude is 60 nautical miles, which lets a navigator read distances straight off the edge of a chart. The knot is one nautical mile per hour, 1.852 km/h, and is the standard speed unit at sea, in the air and in weather reports. A gale, force 8 on the Beaufort scale, begins at 34 knots.

Roman lengths were built on the foot (pes, about 29.6 cm): 16 digiti (finger widths) or 4 palmi (palm widths) made a foot, 1½ feet a cubit, 5 feet a passus (a double step), 10 feet a pertica (perch) and 120 feet an actus, the length of a furrow. Longer distances counted in stadia of 625 feet and in mille passuum, a thousand double steps or 5,000 feet, which is where the word mile comes from; the Gallic leuga was 1½ Roman miles. Milestones along the Roman roads were set one mille passuum apart.