Mariners used to toss a wooden log overboard, and while its line spooled out, they would count each of the knots that passed through their hands.
After 28 seconds, they recorded their boat's speed in knots, or nautical miles per hour.
Today, 200 years later, boaters look at their digital instrument panel and still see their speed in knots.
That tradition was nearly subverted when the Newport Beach Harbor Commission voted in April to change the city's municipal code to measure speed in miles per hour, a slightly slower measure than knots.
The change would make the city's law consistent with the county's. But a few dedicated sailors protested the maneuver, and the harbor commissioners will reconsider their reforms Wednesday.
"We live in a nautical world, and we use nautical miles per hour," said Andy Rose, a member of Balboa Yacht Club who believes the commission should reverse its recommendation to the City Council.
Rose pointed out that most maritime speedometers display speed in knots.
But markers in the harbor — most of which belong to the county — are in miles per hour, and the Orange County Sheriff's Department Harbor Patrol would like the laws to be aligned.
"It just makes everything consistent and everything transparent to the boaters," said Lt. Tom Slayton, the harbormaster.
As it stands, the county limit is five miles per hour and the city limit is five knots.
The difference is inconsequential when it comes to safety and enforcement, Slayton and others say. One knot is equivalent to about 1.15 mph.
Furthermore, deputies, without using radar, typically warn any boaters they see grossly exceeding the limit or creating a large wake.
"I can see a reason for doing it either way," said Commissioner Doug West, who chairs the Speed Limit Subcommittee. "We tend to think in [nautical] terms, so changing it to miles per hour is awkward."
West said the Harbor Commission wants to decide on the issue soon, so it can advance its other speed limit recommendations to the City Council. For years, sailors have sought an exception to the limit during regattas, and the City Council is almost ready to vote on that larger issue.