Often referred to as water-witching or water divining, dowsing is not necessarily concerned with locating water. But it can be used to discover the whereabouts of other natural substances, people, objects, or the source of illness.
Dowsing as a form of divination was practiced in ancient Egypt and may be even older; it is known all over the world. Because of it's high success rate, in the Middle Ages dowsing was associated with witchcraft (Luther proclaimed that it was the work of the devil), but Christian dowsers managed to escape stigmata by "baptizing" their dowsing rods and giving them Christian names.
In the popular imagination, the dowser's tool is a forked rod, but it may also be an angled rod, such as a coat hanger; a wand; or a "bobber," a weighted branch, or a pendulum. Dowsing rods are usually fashioned from willow, rowan, ash or metal (particularly aluminum and copper), plastic and bone may be used too.
In practice the dowser concentrates hard when "tuning" the rod, then walks across (or stands over a map of) the location believed to hold the substance in question.When the rod detects the presence of the substance, it jerks violently. No one knows exactly how dowsing works, but it is commonly believed that dowsers have an innate psychic ability.
As in Feng Shui, the dowsers ability to "connect" with the inherent characteristics of the surroundings or landscape is also important. Other explanations include the sensitivity of the dowser's tools to electromagnetic and electrostatic force fields.
With the nineteenth century advances in scientific knowledge, dowsing correspondingly declined. It regained it's popularity in the twentieth century largely as the result of the efforts of the French priests Alexis Mermet, Alex Bouly (who re-named it "radiesthesia") and Jean Jurion.
Now quite well established and respected, dowsing has been successfully used in fields of archeology, geology and in the search for oil, gas and minerals - and even to try to locate missing persons and explosive mines (as in Vietnam).
Although medical dowsing is prohibited in the United States, it has been used elsewhere to diagnose illness, usually by rotating a pendulum over the patient's body.
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