However, many consider dowsing a controversial practice or even pseudoscience, with no scientific or widely accepted explanation for what influences the response or how and why the practice works. Various explanations have included disturbed soil, magnetic fields, piezoelectric properties of bone, radiation fields, extrasensory perception, cryptesthesia, divine intervention, or other paranormal phenomena.1
dowsing
There has been little, if any, objective testing of dowsing for buried bodies. Nonetheless, it has been advocated as an effective method and is even included as part of some crime scene investigator training programs,6 including those provided to U.S. government agencies. Dowsing is also referenced in some archaeological contexts for detecting underground disturbances and features.7
However, others question the ability to locate buried bodies using dowsing rods. Skeptics believe that advocating dowsing and similar unsubstantiated practices gives false hope to investigators and loved ones, in addition to being an ineffective use of resources. Informal tests of dowsing for graves report uncertainty and suspicion of its effectiveness8 and suggest more rigorous tests may provide further clarification.
The success of each group was evaluated statistically based on whether the holes identified by each participant as containing bones represented a true positive (correctly selecting a hole that contained bones), true negative (correctly not selecting a hole that did not contain bones), false positive (incorrectly selecting a hole that did not contain bones), or false negative (incorrectly not selecting a hole that did contain bones). Results indicated that there was no relationship between the dowsing rod response and the actual locations of the bones. Further, there was no significant difference in the ability to correctly identify the locations of bones between the dowsing group and the participants who visually assessed the graves.
Some practitioners continue to advocate dowsing or other scientifically questionable search methods, even charging investigators or families substantial fees for these services. Unreliable or unsubstantiated search methods can have detrimental effects on an investigation, including unnecessary financial expenditures, time and other resource costs, and false hope among investigators and loved ones. Therefore, it is important that such techniques are well-understood and rigorously tested and that investigators seek and employ methods that are appropriate, reliable, and valid.
In the sense that it finds underground water, water dowsing does not work. Water dowsing involves the claim that a person can locate underground sources of water without using any scientific instruments. Typically, the person that is dowsing holds sticks or rods and walks around a property in the hopes that the rods will dip, twitch, or cross when he walks over the underground water. The dowsing rods do indeed move, but not in response to anything underground. They are simply responding to the random movements of the person holding the rods. The rods are typically held in a position of unstable equilibrium, so that a small movement gets amplified into a big movement. The movements of the rods do not seem like they are coming from the small vibrations in the dowser's arms, since these vibrations are so small and the rod's movements are so large. From the false assumption that the movements of the rods are not coming from the small random vibrations of the dowser's arms, people then make the illogical leap that the movements must therefore be caused by something powerful that is out of sight, i.e. underground water. Since successfully locating underground water can save a farmer the trouble of digging several wells that end up dry, and since scientific approaches can be expensive, there is a strong incentive for people to want water dowsing to work.
Unstable equilibrium describes a state where all the forces on an object cancel out but the slightest deviation from the point of equilibrium causes the object to fly off. For instance, if you place a marble on exactly the top edge of a sharply-ridged roof, the marble will sit there motionless since the forces pulling it down either side of the roof cancel out. However, if the slightest breeze blows past the marble, it will give the marble a small bump toward one side of the roof. The forces will no longer cancel and the marble will shoot down one side of the roof. Since the marble was in a state of unstable equilibrium, gravity was able to amplify a small movement invisible to humans (the bump from the gentle breeze) into a large movement (the marble rolling down the side of the roof). To the naked human eye, it looks like a power agent exists only on one side of the house and is drawing the marble towards it. If we didn't understand the concept of unstable equilibrium, we may be tempted to say that there is underground water only on the one side of the house which pulled the marble down that side. Belief in water dowsing operates on this type of misunderstanding.
The belief in dowsing typically involves the misunderstanding that underground water consists of large underground rivers flowing through caverns. In this thinking, one spot on a farm would be a good location to drill a well because it is lined up with the underground river, whereas another spot 20 feet away would be a bad location since it misses the underground river. In reality, most underground water does not flow in rivers but instead flows everywhere through the tiny pores and cracks in the rocks. In any climate that receives a moderate amount of rainfall, you will always hit water if you dig deep enough. Therefore, the question to ask is not, "What spot on my farm has water underneath it?" Every spot has water underneath it. The right question to ask is, "How deep will I have to dig to get below the water table?" Another important question to ask when drilling a well is, "Does my ground contain the right kind of rock that will release its water fast enough to fill my well?" Even if there is water in the ground, a dense rock with small pores may release its water too slowly to be useful.
Various controlled scientific studies over the last hundred years have repeatedly found that water dowsing does not work. For instance, 30 "expert" dowsers were invited to Kassel, Germany in 1990 to have their abilities tested in a study organized by James Randi. Pipes carrying flowing water were buried underground at known locations and the dowsers were tested as to their ability to determine if water was flowing through the pipes. All failed to do better than random guessing. In the book Carl Sagan's Universe, edited by Yervant Terzian and Elizabeth Bilson, James Randi describes the tests:
While we were there we designed a series of tests, as I have done in many countries around the world, to test the forked stick or the pendulum or the coat hanger wires or whatever. Some people do it with their hands. And we did it in Kassel, Germany, two years ago, a very definitive set of tests, and, of course, it proved that the law of averages works quite well, but dowsing doesn't.
The dowsing that most people are familiar with is water dowsing, or water witching or rhabdomancy, in which a person holds a Y-shaped branch (or two L-shaped wire rods) and walks around until they feel a pull on the branch, or the wire rods cross, at which point water is allegedly below. Sometimes a pendulum is used held over a map until it swings (or stops swinging) over a spot where the desired object may be found. Dowsing is said to find anything and everything, including missing persons, buried pipes, oil deposits and even archaeological ruins.
Part of the reason for dowsing's longevity is its versatility in the New Age and paranormal worlds. According to many books and dowsing experts, the practice has a robust history and its success has been known for centuries. For example in the book "Divining the Future: Prognostication From Astrology to Zoomancy," Eva Shaw writes, "In 1556, 'De Re Metallica,' a book on metallurgy and mining written by George [sic] Agricola, discussed dowsing as an acceptable method of locating rich mineral sources." This reference to 'De Re Metallica' is widely cited among dowsers as proof of its validity, though there are two problems.
Furthermore, it seems that the dowsing advocates didn't actually read the book because it says exactly the opposite of what they claim: Instead of endorsing dowsing, Agricola states that those seeking minerals "should not make use of an enchanted twig, because if he is prudent and skilled in the natural signs, he understands that a forked stick is of no use to him."
If dowsing could be proven to work, what could the mechanism be? How could a twig or two metal wires know what the dowser is looking for (water, money, minerals, a lost item, etc.), much less where it could be found? The proposed mechanisms are as varied as the dowsers themselves. Some sources claim that strong psychic energy is radiated by the object and detected by the dowser; others believe that ghosts, spirits or mysterious Earth energies direct the dowser to their targets.
Skeptic James Randi in his "Encyclopedia of Claims, Frauds, and Hoaxes of the Occult and Supernatural," notes that dowsers often cannot agree on even the basics of their profession: "Some instructions tell learners never to try dowsing with rubber footwear, while others insist that it helps immeasurably. Some practitioners say that when divining rods cross, that specifically indicates water; others say that water makes the rods diverge to 180 degrees."
Though some people swear by dowsing's effectiveness, dowsers have been subjected to many tests over the years and have performed no better than chance under controlled conditions. It's not surprising that water can often be found with dowsing rods, since if you dig deep enough you'll find water just about anywhere. If missing objects (and even missing people) could be reliably and accurately located using dowsing techniques, it would be a great benefit: If you lose your keys or cell phone, you should be able to just pull out your pendulum and find it; if a person goes missing or is abducted, police should be able to locate them with dowsing rods. 2ff7e9595c
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