Where does knots come from?

Answer 1

Knots is the form of measurement of the speed of boats. It was originally measured by a board being dropped in the water with a rope tied to it, the other end of the rope was tied to the stern of the boat. This rope had knots tied into it at 14.4 meters apart. The one sailor would use a 30 second glass sand timer while another would let the rope out behind the boat. When 30 seconds were up the number of knots on the rope that had gone thru the sailors hands were the speed they were traveling. Dividing that 14.4 meters by 30 seconds told them that one knot equaled 1.85166 kilometers per hour, or one nautical mile.