Mark on ship side to show how far it may be loaded?

The mark on a ship's side indicating how far it may be loaded is called the "load line" or "Plimsoll line." This line ensures that a vessel is not overloaded, which can compromise its safety and seaworthiness. The load line is usually marked with a horizontal line and various symbols or letters indicating the maximum allowable draft for different water conditions. Proper adherence to this mark is crucial for maintaining stability and buoyancy while at sea.