The Plimsoll line is a reference mark located on a ship’s hull - TopicsExpress

The Plimsoll line is a reference mark located on a ship’s hull that indicates the maximum depth to which the vessel may be safely immersed when loaded with cargo. This depth varies with a ship’s dimensions, type of cargo, time of year, and the water densities encountered in port and at sea. Once these factors have been accounted for, a ship’s captain can determine the appropriate Plimsoll line needed for the voyage. Samuel Plimsoll (1824–1898) was a member of the British Parliament who was concerned with the loss of ships and crews due to vessel overloading. In 1876, he persuaded Parliament to pass the Unseaworthy Ships Bill, which mandated marking a ships sides with a line that would disappear below the waterline if the ship was overloaded. The line, also known as the Plimsoll mark, is found midship on both the port and starboard hulls of cargo vessels and is still used worldwide by the shipping industry. From What is a Plimsoll line?, oceanservice.noaa.gov/facts/plimsoll-line.html Thanks to Pride of Baltimore II and the National Oceanic and Atmospheric Administration (NOAA) for the shares.