[snip] Then you measure > distance by tossing a big chunk of lumber overboard with a measured > rope tied to it. The captains hated doing math by hand so they > calibrated the rope by tieing knots at intervals so the natural unit > was one arc minute at the equator and called it a "knot".
Nope. A knot is a unit of velocity, not didtance. A "knot" is 1 nautical mile per hour A nautical mile is that distance, subtended at the earth's surface at the equator, by 1 arc-minute. If somebody tells you the ship was going "22 knots/hour" they don't know what they are talking about. A knot/hour is an acceleration. I've only seen knots/hour used correctly once, in an inertial guidance system, for cross-track acceleration. > My buddy who was headed to hawaii put both GPSes in the oven in the > galley and after three days was able to get one of them to work a few > minutes a couple times a day. That was enough. But he said he was > within maybe 15 miles of where he thought he was > > Basically your estimated course line intersected with a line of > latitude gives you longitude. -John ==================== _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.