Tagmeasurement

“Cord” of Wood

David from Plymouth, Wisconsin, wonders about the expression a cord of wood. The phrase goes back to the 17th century and has to do with using a cord to measure a specific quantity of stacked wood. This is part of a complete episode. Transcript of...

Sea Knots

Why are distances at sea measured in knots? In the 1500s, sailors would drop a chip log off the side of the boat and let out the rope for about thirty seconds, counting how many knots on the rope went out. Eventually, one knot came to mean one...