Dowsing

Dowsing is a practice of divination in which a practitioner attempts to locate groundwater, buried metal, gemstones, oil or other hidden objects and materials without any technical equipment or scientific instrument, typically using a forked Y-shaped twig or a pair of L-shaped rods said to move toward the target; it is also called divining, especially for water, doodlebugging in petroleum prospecting, and water witching in American usage. The motion of a dowsing rod is generally attributed to unconscious muscle movement, called the ideomotor phenomenon, or to ordinary chance rather than to any real detecting ability, and controlled tests have found dowsing no more effective than random guessing, so it is regarded by the scientific community as a pseudoscience. The practice dates to antiquity, was condemned by the Catholic Church and by Martin Luther as a violation of the first commandment, and its earliest documented reference to water dowsing specifically dates to 1568, in an account involving Saint Teresa of Spain.