he reel be free-spinning, to allow the line to pay out without friction.
E. The glass is made from an egg timer. One end of the glass is carefully opened with a Dremel tool with a dental burr or drill. This is extremely difficult, as too much pressure will break the glass. After opening the glass, get a stopwatch and a piece of clean paper. Being careful to coordinate the watch and glass, invert the timer and pour out 2:32 worth of sand on to the paper. At the 2:32 point, turn the glass horizontal. Reset the stopwatch, and turn the glass back upright as you start the stopwatch again, letting the sand return to the "bottom" half of the glass. Stop the watch as the sand finishes flowing; you should have measured 28 seconds. If the time is too long, pour off a small amount of sand, if it is too short, add sand back into the glass.
To use the log requires two men; one to hold the reel aloft, facing aft at the taffrail, and one to drop the drogue overboard, turn the glass, and stop the line when the sand runs out. The actual time for the reading is 30 seconds; the time required to drop the drogue overboard and turn the glass accounts for about two seconds; this is the reason for the odd amount of sand in the glass. After stopping the line, the number of knots payed out is the speed of the ship; it's as simple as that.
To retrieve the drogue, rather that reeling it in against the dead drag of the upright board, just give the line a quick, very sharp tug, and the peg, snugly fitted into the drogue, will pop out, letting the board flip parallel to the flow of the water and allowing for easy retrieval as it skips across the surface of the sea.