The Plimsoll Mark for Ships The Plimsoll Mark is what you see on every ship's hull and indicates the extent to which the vessel may be loaded with safety under varying conditions. W IS : FW--Fresh Water S IS--Indian Summer W--Winter (Salt Water ) (Salt Water ) WNA--Winter North Atlantic S--Summer (Salt : (Salt Water ) Water ) W WNA Samuel Plimsoll was born in England in 1824. In 1868 he became a member of the House of Commons, and immediately set about trying to improve safety conditions at sea. At that time many worn-out and poorly equipped ships were in use, a number of them badly overloaded, thus not only subjecting their crews to poor living and working conditions, but even at times endangering their lives. After vainly trying for six years to have legislation passed to improve these conditions, Plimsoll was finally successful--and the "Merchant Shipping Act 1876" went into effect. Plimsoll also gave much of his time and money to further reforms at sea, and finally died at Folkestone in 1898. The "Merchant Shipping Act 1876," together with its later amendments, still serves today as the governing factor for the safety of British ships at sea, and the Plimsoll mark, with very few changes, has been adopted by practically every maritime nation. The Plimsoll load-line mark on the side of a ship's hull is a circle 12 inches in diameter, with a horizontal line 18 inches long drawn through its center. Its position on the hull is determined by regulations governing the method of determining the load line. Twenty-one inches forward of the center of the circle is a vertical line which is joined at right angles by other lines 9 inches in length which show the maximum load lines at different seasons and under various conditions. The lines extending toward the bow of the ship refer to salt water operation, while the line extending aft is for fresh water service. Copyrighted by Fred W. Green, 1945 504