A deadeye, or deadman’s eye, is a cylindrical disc with one or multiple holes that has traditionally been the method of guiding rigging and increasing sail tension in sailing ships. It is usually made of wood with rope or an iron band wound around the perimeter. The two most common types of deadeyes are those with one hole, also known as the bulls eye, and those with three holes. Single deadeyes are usually used alone, while the triple hole varieties tend to be used in pairs.
The location of deadeyes depends on the number of holes. A single-hole deadeye is often placed high on a mast where it can help to guide a line. Triple-hole deadeyes are usually anchored on the edge of the ship’s railing where they help to secure lines. Once lines are drawn through the deadeyes they are pulled tight via pulleys or other similar mechanisms. The deadeyes help to maintain that tension in the proper place.
In many modern ships the single deadeye has been replaced by a kind of pulley known as a block. Instead of being secured to the side of the ship, the block is threaded directly on the line it controls. In older vessels, the single deadeye was usually used guide the ship through direction changes or simply to guide lines, also known as lanyards, for the sails.
Pairs of the triple deadeye are usually used to guide a line across a sail. They extend the lines which keep the mast sails up, also known as shrouds, and create a sort of pulley to increase tension in the sail. Another of their functions is to help to guide the stays, which are sturdy cables or ropes that are primarily used to provide support for the mast.
Though the deadeye has been replaced to some extent by other mechanisms, it is still in fairly wide use. In some modern sailing ships, lanyards have been replaced by steel wire. Instead of a deadeye, metal turnbuckles, which are long metal pieces with a hook on one end and a loop at the other, are now in more common use. They help to pull the wires tight so that the sails have proper tension.
As the deadeye has been used most frequently in older ships, it has now become a collectible item. There is a wide array of antique deadeyes available for purchase. These are most frequently collected by marine or sailing enthusiasts for display purposes.