Skepticism, Science & Pseudoscience

In 1949, an experiment was conducted in Maine by the American Society for Psychical Research. Twenty-seven dowsers "failed completely to estimate either the depth or the amount of water to be found in a field free of surface clues to water, whereas a geologist and an engineer successfully predicted the depth at which water would be found in 16 sites in the same field.

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Typical is what happened when James Randi tested some dowsers using a protocol they all agreed upon. If they could locate water in underground pipes at an 80% success rate they would get $10,000 (now the prize is over $1,000,000). All the dowsers failed the test, though each claimed to be highly successful in finding water using a variety of non-scientific instruments, including a pendulum. Says Randi, "the sad fact is that dowsers are no better at finding water than anyone else. Drill a well almost anywhere in an area where water is geologically possible, and you will find it."