LIVES ON THE LINE
The Story of the Plimsoll Mark

 

Sailors held one of the riskiest jobs in Victorian England. In the 19th century, thousands of people drowned aboard sailing ships. Merchants would sailors to transport cargo aboard very old ships, even ones that were falling apart. Such ships were called “coffin ships.”

Some dishonest ship owners insured these coffin ships for far more than the ships' actual value. That meant that the ships were worth more to the owners at the bottom of the ocean than they were as working vessels. The sneakiest merchants renamed wooden ships and insured them as new vessels, even though under the fresh paint the wood had rotted away and was full of worms. A boat loaded with too much cargo easily sank on its journey. Many believed that ship owners overloaded their vessels intentionally (or: on purpose). Tragically, many lives were lost whenever a ship went down. The widows and orphans left behind by the drowned sailors demanded a change in laws to prevent shipwrecks.

By the mid-19th century, the British government began to respond to growing concern about the loss of ships and crews. They created laws for how merchant ships operated. The merchants ignored these laws for two decades. One Member of Parliament, Samuel Plimsoll, stepped in to promote the use of a simple drawing on the side of every ship. This drawing could give an objective measure for how safely loaded the ship was. With more cargo on board, a boat sinks lower in the water, and the “Plimsoll Mark” would sink closer to the water line. A fully visible Plimsoll Mark above the water line proved the ship was not overloaded, and the crew, cargo, ship could make their journey safe and sound.

Plimsoll spent decades making passionate speeches in the British House of Commons to help sailors and their communities. He even wrote a popular book, Our Seamen. It described the shocking practices of shipowners. They launched lawsuits against Plimsoll to try to make him stop fighting for reform. Nevertheless, Samuel Plimsoll kept fighting for the lives of sailors until Parliament passed the Unseaworthy Ships Bill in 1876.

Plimsoll’s original line was just a circle with a line through it. Because water is less dense in warmer latitudes and seasons, and denser in the ocean than in freshwater, details have been added to show safe load levels for different latitudes and saltiness.