Dowsing

From SkepticWiki

[edit] Definition

Dowsing is a divination method used to locate water or metals with sticks or rods ("divining rods"). It has also been called "water witching" and "rhabdomancy"

A "water-witcher" traditionally held a forked wooden stick and walked over an area. When the stick moved it was said to signify the presence of water below the surface. A well would be dug based on the dowser's advice.

Some dowsers use a pendulum, or two metal rods, to achieve the same effect.

More recently dowsers claim to be able to locate more than water, such as oil, buried electrical cables, etc. There are also those who claim they can find things merely by waving a pendulum over a map of the area.

[edit] Discussion

James Randi suggests one hypothesis for dowsing is the ideomotor effect, in which a tiny movement of the hands results in a large movement of the dowser's tool. Most of the people who have tried to win Randi's $1 million challenge have been dowsers. To date, no one has won the prize.

Scientific American Frontiers, a TV show on public broadcasting, performed several tests with dowsers. All were unsuccessful. Experts on that show suggested that people were unconsciously motivating their rods or sticks, but most dowsers were apparently of the opinion that their unconscious was channeling from some great repository of wisdom.

Many dowsers are sincere in their belief in there own powers --- as is shown by the fact that they are much more eager than the average psychic to have there abilities tested by skeptics. Some claim that they have no idea how dowsing works, but are sure that it does work. There are also dowsers who have fantastical notions involving invisible rays, lines of 'natural force' and so on.

Despite the lack of scientific evidence, the popularity of dowsing does not seem to abate. Vineyards, ranchers, and farmers commonly employ a dowser's services and those of a geologist or hydrologist. Drillers too are skeptical, but some give it a grudging, although anecdotal, acceptance. To test whether the dowser didn't just succeed by chance, or because if you dig deep enough, you are likely to hit the water table anyway, the dowser's clients would have to dig lots of other wells in the same area. As they hire the dowser to save them this sort of trouble and expense, this sort of test is rarely, if ever, carried out.