Plimsoll Marks

In 1870, Samuel Plimsoll, a member of the British Parliament from Derby, became a hero to mariners everywhere. The British government had been trying to get ship owners to be more careful with the loading of their vessels and to reduce the number of the seamen lost due to overloaded vessels. The ship owners were resistant and men continued to die. Plimsoll railed against the "coffin ships," ships which were insured for more than they were worth:

I earnestly entreat the right honorable Gentleman at the head of Her Majesty's Government not to consign some thousands of living human beings to undeserved and miserable death. … Under the Board of Trade, since 1862, when unhappily the commercial marine of this country was committed to their care, matters have been getting worse and worse, with ... ship owners of murderous tendencies outside the House, and who are immediately and amply represented inside the House, and who have frustrated and talked to death every effort to procure a remedy for this state of things… The Secretary of Lloyd's tells a friend of mine that he does not know a single ship which has been broken up voluntarily by the owners in the course of 30 years on account of its being worn out. Ships gradually pass from hand to hand, until bought by some needy and reckless speculators, who send them to sea with precious human lives… And what is the consequence that ensues? It is that continually, every winter, hundreds and hundreds of brave men are sent to death, their wives are made widows and their children are made 1824 orphans, in order that a few speculative scoundrels, in whose hearts there is neither the love of God nor the fear of God, may make unhallowed gains. There are ship owners in this country of ours who have never either built a ship or bought a new one, but who are simply what are called "ship-knackers…"

Plimsoll next called some of his fellow members of Parliament "villains" for being involved with these shipowners, leading to a confrontation with Prime Minister Benjamin Disraeli and a public rebuke by the House of Commons. His cause won the day, however, and the load lines we see on the sides of ships today are named in his honor.

The lines are marked and labelled to show the safe limit to which a vessel can be loaded. The basic abbreviations and lines are

TF Tropical Fresh Water

F Fresh Water

T Tropical Seawater

S Summer Temperate Seawater

W Winter Temperate Seawater

WNA Winter North Atlantic

The "L" next to the lines on the left above indicates "timber," whose effect on stability is measured slightly differently. The circle with the line through it is the maximum load line. The "LR" indicates the vessel's classification society, in this case "Lloyd's Register."

Other marks. The numbers shown here indicate the vessel's draft, or the amount of it that is beneath the water. There are also marks indicating a bow thruster (left, middle) and a bulbous bow (left, bottom).

Plimsoll's own 1873 work, Our Seamen: An Appeal can be found at googlebooks here.

Professional Mariner awards a "Plimsoll Award" each year to people or organizations that "embody the spirit of Samuel Plimsoll." For more on the award, click here.