Load lines are painted on the side of ships to show how low it may safely rest in the water. Although usually associated with the British MP Samuel Plimsoll (1824–1898), seafaring societies had marked the sides of their ships hundreds of years earlier. Ships from Venice were protected in this way by the marking of a cross, the traditional symbol of salvation, as long ago as the 12th century. The city of Genoa also marked its ships in a similar way, using a sign made up of three horizontal bars. However, the custom died out, and it was not until the 19th century that the use of load lines became widespread.
Why should a ship not be overloaded?
When seafaring merchants began to transport goods by sea, they soon realised the importance of loading their ship correctly. If a ship was overloaded it could sink in heavy seas or rough weather. Although they understood this, shipowners were sometimes tempted to risk overloading because of the huge profits that could be made when large cargoes were sold abroad. If a ship were lost at sea, owners would not suffer financially because they could claim back insurance money.
Were many ships lost?
Yes. For example, in the year 1873–74, around the coastline of the United Kingdom, 411 ships sank, with the loss of 506 lives. Overloading and poor repair made some ships so dangerous that they became known as 'coffin ships'.
Why did the question of safety become more important in the 19th century?
During the 19th century, British trade with the rest of the world was growing rapidly. The large number of ships being wrecked each year caused greater and greater concern. One of the first attempts to get ships to carry loading marks for safety was made in 1835 by Lloyd's Register, a classification society. Lloyd’s Register introduced freeboard tables for loading, but these only applied to those ships classed by Lloyd's Register itself. Other ship owners could still do as they pleased when they loaded their ships. If they chose to disregard questions of safety no-one would stop them.
Did sailors worry about the dangerous condition of ships?
Yes, and many refused to go to sea. In 1855, a group of sailors calling themselves 'The seamen of Great Britain' wrote to Queen Victoria complaining that courts had found them guilty of desertion when they complained about going to sea in dangerous ships. Around the same time, an inspector of prisons reported that nine out of twelve prisoners in the jails of south-west England were sailors, imprisoned for twelve weeks for refusing to sail in ships they considered to be unseaworthy or without enough crew. In one case in 1866, several whole crews were jailed, one after the other, when they refused to set sail in an old ship named Harkaway. The sailors complained that even at anchor on a calm sea, the ship took in water to a depth of more than a metre each day. The Harkaway did not finally set sail for the West Indies with its loaded cargo until it had taken on board its fifth crew.
How did Samuel Plimsoll become involved with the problem of ship safety?
Different attempts, like that of Lloyd's Register, were made over the years to ensure that only safe amounts of cargo were loaded, but there was still no compulsory system to force ship owners to act to protect their ships. In 1870, the MP Samuel Plimsoll, who was a coal merchant, became interested after attending a meeting on the subject. He began to write a book about the disastrous effects of overloading ships.
What did Plimsoll discover?
When he began to investigate, Plimsoll found the problem was even worse than he had expected. He began to campaign in parliament with the aim of improving safety at sea. Many ordinary people became very interested in his book and his campaign. In 1872, a Royal Commission on Unseaworthy Ships was set up to look at evidence and recommend changes. Despite several defeats in parliament, Plimsoll continued in his fight until load lines became compulsory. He became so famous that several popular songs were written about him. The verses below are from A Cheer for Plimsoll, written and sung by Fred Albert in 1876.
So a cheer for Samuel Plimsoll and let your voices blend
In praise of one who surely has proved the sailors' friend
Our tars upon the ocean he struggles to defend
Success to Samuel Plimsoll for he's the sailors' friend.
There was a time when greed and crime did cruelly prevail
and rotten ships were sent on trips to founder in the gale
When worthless cargoes well-insured would to the bottom go.
And sailors' lives were sacrificed that men might wealthy grow.
For many a boat that scarce could float was sent to dar the wave
'til Plimsoll wrote his book of notes our seamen's lives to save
His enemies then tried to prove that pictures false he drew
but with English pluck to his task he stuck, a task he deemed so true.
When did the use of a load line become compulsory?
The Merchant Shipping Act of 1876 made load lines compulsory. However, the position of the line was not fixed by law until 1894. In 1906, foreign ships were also required to carry a load line if they visited British ports. Since then, the line has been known in Britain as the Plimsoll Line. To this day, it still carries the name of the MP who fought such a long struggle in parliament to win better safety conditions for ships' crews. Together with other important changes made to ships in the Victorian period, load lines helped to preserve the lives of ships' crews and passengers.
How did the load line work?
It was painted on the side of merchant ships. When a ship was loaded, the water level was not supposed to go above the line. However, the water could reach different parts of the line as its temperature and saltiness varied with season and location. The basic symbol, of a circle with a horizontal line passing through its centre, is now recognised worldwide.
The load line today
The Oxford Companion to Ships and the Sea defines the Plimsoll Line as:
... A mark painted on the sides of British merchant ships which indicates the draught levels to which a ship may be loaded with cargo for varying conditions of season and location. The Plimsoll Mark shows six loading levels, those which may be used in tropical fresh water; fresh water; tropical sea water; summer, sea water; winter, sea water; and winter, North Atlantic, for vessels under 100 metres (330 ft) in length.
The Oxford Companion to Ships and the Sea, ed. Peter Kemp (Oxford University Press)