Pendulum
The pendulum is a simple divinatory tool: a weight suspended on a thread that swings to answer yes/no questions or to locate things. Used in radiesthesia, alternative practice popularized in the 19th-20th centuries. Movement explained by the ideomotor effect (Carpenter, 1852).
Common uses
Yes/No questions (clockwise/counter), water dowsing, finding lost objects, food sensitivity testing, energy diagnosis. The professional dowser holds a long pendulum over maps to "find" wells, treasures, missing persons.