Dowsing

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Pseudoscience Alert
This topic is a pseudoscience, and is not accepted by the scientific community as a valid discipline.
Although it may use scientific terminology, it does not use scientific methodology.
Remember: just because it sounds right doesn't mean it's actually right.

Dowsing is the attempts to detect "hidden" things, such as water, gems, and gold, under various surfaces. It is most commonly associated with looking for water for drilling of wells. So called "water witches" make a living telling people where to drill for water wells. Practitioners use dowsing rods (usually made of wire or a forked twig, but let's face it, anything would do), to detect these hidden sources of wealth. The rod appears to move up and down outside of the practitioner's control. This is actually due to the Ideomotor effect where small muscle movements in the arms and hands cause the dosing rod to move up and down. These muscle movements can be completely involuntary but are often voluntary in the sense that anticipation on the part of the practitioner may cause them to increase in force and frequency. Much of the ideomotor effect is outside of direct conscious experience, so the practitioner doesn't realize he is doing it, though it is more than conceivable that some "water witches" know what's going on and are consciously defrauding people.

All controlled studies of dowsing have demonstrated that it is completely false and that dowsers are no better than chance at detecting hidden metals or water. The continued support for dowsing is probably due to the phenomenon that if you dig down deep enough you will eventually find water. A dowser could point at random and the person could dig, and eventual hit water. This is nothing special about the dowser.

Dowsing has also recently taken a more dangerous and sinister route with companies marketing special rods designed to detect explosives and land mines.^[1]

For those who wish to believe that ersatz controls and and rudimentary electronics make for a better dowsing rod, a number of entrepreneurs have developed dowsing rods with these sorts of fancy decorations called "long-range locators", enabling would-be dowsers to spend far more money with less unnecessary logic or common sense than they normally would on their equipment. Metal detector geek Carl Moreland reviews a number of them at geotech.thunting.com. Prices for such devices run into the thousands of dollars, with most units being little more than an assembly of naively-wired electronics and embarassingly shoddy workmanship.

On the Channel Island of Jersey (not part of UK) a dowser recently cost a small fortune by convincing the Gov't that underground water was reaching the island's aquifer via subterranean rivers from France. ^[2]