Valuable magic items that are useless in combat

[phiwum]

Originally Posted by amenditman

Yes, knots in a line (rope).

I was speaking about the unit, not actual knots in a line, but since the latter is the etymology for the former (which I didn't know), I guess we're on the same path.

Strictly speaking, according to WP, knots in a line were used to measure a vessel's speed through the water, not windspeed.

I had always assumed that "knot" was derived from "nautical miles per hour" using the sound of the first syllable.