From RationalWiki
Jump to navigation Jump to search
A farmer dowsing in 1942
Style over substance
Icon pseudoscience.svg
Popular pseudosciences
Random examples
Gather 'round the campfire
Icon folklore.svg
Urban legends

Dowsing is the attempt 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 dowsing rod to move up and down.[1] 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 she or he is doing it, though it is more than conceivable that some "water witches" know what's going on and are consciously defrauding people.

The technical term for dowsing is rhabdomancy (IPA — /ˈræb.dəˌmæ A dowser is a rhabdomantist. A dowsing rod is a rhabdom (pl. rhabdoms.)


The graph at the top represents actual results from the Munich tests. The two graphs at the bottom represent what you would expect from chance. If dowsing actually worked, all the points would be aligned in a diagonal line.

Numerous controlled studies of dowsing (the first one being conducted in 1641[2]) have consistently demonstrated that it simply doesn't work; 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 eventually hit water. This is nothing special about the dowser or the forked stick, coat hanger, or other "equipment" he or she is using.

And then Randi came along and ruined everything[edit]

Dowsing has been tested, among others, by James Randi. Not surprisingly, no dowser managed to demonstrate accuracy better than that of pure chance in the experiments, even though all claimed to have accuracy around 100%. The tests were:

  • A zinc ore was hidden under one of seven boxes and the dowser was tasked with finding this box. The rod was bending and springing as if demonically possessed during the control sample, but when the actual test began it took him three attempts to point to the right box which is also the number you would expect if he was guessing.[3]
  • Ten pipes were placed underground. Water flowed only through one pipe and a group of dowsers were, just like in the previous experiment, tasked with finding the correct one. As before, the results from the control sample differed vastly from the results of actual tests. No dowser showed accuracy greater than that of chance and hence no one won the $40,000 prize.[4]

Randi also explained the ideomotor effect by analysing a video of a dowser and even after pointing it out to him, the dowser refused to believe that the motion of the rod is caused by no one other than himself.[5]

Tests in Poland[edit]

A number of studies on radiesthesia have been carried out in Poland over a period of more than 10 years in various locations during ten scientific camps. The scientists carrying out the tests were initially in favour of radiesthesia, but the results of the tests contradicted their initial theses causing them to change their minds. About 300 people were tested. The tests conducted were[6]:

  • The following hypotheses were investigated and refuted: electrostatic field hypothesis, anomaly of a constant magnetic field hypothesis (Ives Rockard), the generation of the 21-centimetre electromagnetic wave hypothesis (Prof. Rotkiewicz), electrokinetic hypothesis, compensation loop hypothesis, magnetic field shifted in phase hypothesis.
  • Showing that the ideomotor effect does play a major role in the rod movements.
  • Showing that, similarly to the tests conducted by Randi, dowsers were able to "feel" the current in a wire as long as they were sure whether the circuit was closed and failed to do so, or act as if they were guessing, when they were not sure of it (didn't see anyone turning it on or off).
  • Checking various places for the alleged water veins.

The conclusions were as follows:

  • Firstly, water veins do not exist.
  • Secondly, even if they did exist, the radiation attributed to them has properties contrary to what is known about it from modern physics.
  • Thirdly, any radiation emitted by flowing water would be undetectable by living organisms. Even the most sensitive measuring equipment does not register this radiation, even though it can be used to detect archaeological artefacts hidden beneath the earth's surface.

Additionally, other various tests were carried out to check whether dowsing actually works. The radiesthesists were given a plan of the house and a plan of one of the rooms located in the house. Their task was to find the water veins. The places they pointed out varied considerably. In another experiment, a radiesthet identified the location of water veins in a room that did not exist.[7] In yet another experiment, the diviners were told to pinpoint the location of the water veins in a 10x10 metre area, each of the diviners pointed to different places.[8]

Dawkins' attempt[edit]

In his film The enemies of reason, Richard Dawkins conducted a test with the psychologist Chris French on a few dowsers. There were eighteen containers, seventeen of them containing a bottle of sand, one of them containing a bottle of water. No dowser managed to perform better than by chance.[9]

Munich tests[edit]

In Germany, Munich in 1986 an experiment was conducted in a barn with some 500 dowsers. They were placed in the upper part of the barn, while in the lower part there was a pipe with water whose position changed each time. The task of the radiesthesists was to pinpoint this position. As you can imagine, the result was a disaster. It is true that, as the paper claims, several of the diviners showed very good results, but with 500 of them, this is not surprising at all.[10] Once plotted onto a graph, the result are indistinguishable from random numbers.

Physical problems[edit]

Dowsing requires that there be a force or an interaction between the dowser and water, ores or whatever it is. There are three possible scenarios: either the material sends some "signals" to the dowser, the dowser sends some signals to the material and they bounce off it, or there is a constant flow of these signals through the earth and the material just casts a shadow.

The fifth elementary force[edit]

Scenarios one and two assume the existence of some force that would cause the interactions. We know of four elementary forces: electromagnetism which is responsible for light and chemical reactions, weak force which is responsible for radioactive decay, the strong force which binds quarks together to form protons and neutrons and the gravity responsible for objects attracting each other.[11] No other force has been observed, although many have been proposed to explain some of the mysteries of physics (none of them is obviously related to dowsing).[12] Since the very existence of such a force hasn't been established yet, it's futile to build hypotheses about it.

This explanation also requires that there be some boson which would carry that force. This is because all the particles can be divided into two groups: those that carry forces (called bosons) and those that are affected by them (called fermions). Electromagnetism is carried by photons which can be absorbed by any charged particles, the strong nuclear force is carried by gluons and interacts with quarks, the weak nuclear nuclear force is carried by bosons W± and Z0 and interacts with all fermions.[13][note 1] This raises a lot of problems. We haven't found that particle even though we know it would certainly interact with quarks and electrons (after all, that's what we're made of, and the diviners (or the rods) are supposed to "feel" the radiation). One might ask then: why is it that your electrons can interact with it, but mine can't and how come that a force that can make you barely walk and bend rods hasn't been yet detected by anything? We would certainly notice some anomalies by looking at what happens to electrons (and hadrons) near water, but we have found no such anomalies that cannot be explained by any of the four forces. So it seems that while the alleged radiation is supposed to be falsifiable, it is highly questionable.

The distortion hypothesis[edit]

The third scenario requires that there is a general field of some radiation that goes through the earth and can be distorted by some of the materials within it. These distortions can then be recognised by the dowsers. This hypothesis is no more plausible than the previous one because it faces exactly the same problem of what this force is, what carries it and why it can only be detected by a handful of people.

Various model of this hypothesis have been tested during the tests conducted in Poland and no such force has been observed.

"Modern" dowsing[edit]

For those who wish to believe that ersatz controls 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. Prices for such devices run into the thousands of dollars, with most units being little more than an assembly of naively-wired electronics and embarrassingly shoddy workmanship. Apparently, the Iraqi government has bought a ton of these (ADE-651) for finding bombs in passing cars.[14] The UK-based purveyor of these devices was convicted of fraud in 2013.[15]

One dowsing products company has also taken a more dangerous and sinister route with special rods claimed to detect explosives and land mines.[16]

Hilarity ensues[edit]

On the Channel Island of Jersey (not part of the UK but part of the British Isles) a dowser cost the local government a small fortune in 2007 by convincing them that underground water was reaching the island's aquifer via subterranean rivers from France.[17]

The majority of UK water companies confirm that some of their engineers use dowsing to locate leaks, although most companies claim they do not encourage the use of dowsing.[18]

See also[edit]

External links[edit]


  1. The boson of gravity - the graviton - has not yet been found, probably due to the incompatibility of general relativity and quantum mechanics.