Landmark Navigation Rule, a New Navigation Device

Two new methods of landmark navigation were recently presented. The landmarks are assumed to be within sight of the navigator but with unknown positions. Both methods require computations which are time consuming when a computer is not available. This correspondence presents the concept of a new navigation device called ¿landmark navigation rule¿ which eliminates all the computation effort required in both new methods. The device is simple in construction, lightweight, and consumes no power.