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Dowsing: Dowse It Work?

You can鈥檛 find water with a stick. But the debunked technique of dowsing may be making a comeback because of a global phenomenon.
Image by Traite De La Physique Occulte/Bettmann Archive.

Desperate times call for desperate measures, I suppose. Although we live in a world driven by technology, we are always one cataclysm away from retreating to magical notions. Climate change is , which will increase the value of water moving forward. An ancient pseudoscience is poised to make a resurgence in these desperate times.

It's been called water witching, radiesthesia, divination or, simply, dowsing. It consists in finding objects, traditionally water, that cannot be detected by our five senses. In a typical write-up, the Boston Globe last fall . The article sandwiches scientific facts in between anecdotal reports of the 鈥淚 don鈥檛 know how it works but it did鈥 variety. The reader will be left with the impression that if they are ever thirsty for a new source of water on their land, calling upon a dowser would make perfect sense.

But divination is not limited to finding water. Its services are offered to find oil, buried objects, lost vessels at sea, missing persons, archaeological artefacts, buried pipes, and food impurities. Basically, move over Saint Anthony: we have ourselves a new patron saint for lost objects. The French priest who, in 1927, gave dowsing the scientific sounding name 鈥渞adiesthesia鈥 (which means to sense with a rod) claimed . He could also find intact shells buried in the ground during the Great War and somehow tell if they were German, French, or Austrian.

Dowsing is traditionally done with the help of a device the movements of which are said to be influenced not by its holder but rather by鈥 something else. This mysterious mover is claimed by different practitioners to be water energy, earth energy, even spirit guides. One of the best-known dowsers in the world, Leroy Bull, says . The Canadian Society of Dowsers is : 鈥淚 wish I could give you a rational explanation for dowsing. But to date, there is no explanation, scientific or otherwise, as to how dowsing works. There are just theories.鈥

Dowsers use a pendulum, or a Y-shaped rod, or two L-shaped rods that rotate above the handles, and it is the movement of these devices that gets interpreted as 鈥測es鈥 or 鈥渘o鈥 by the water witcher. Is there water underneath my feet, they might ask? The L-shaped rods, one held in each hand, will cross into an 鈥淴鈥 shape if the answer is yes. Is it deeper than a hundred feet? The Y-shaped rod will start pointing to the ground to say yes. Is it deeper than two hundred feet? The pendulum will swing left to right to indicate no.

By now, it should be obvious that dowsing is not scientific. Nothing in our current understanding of the laws of physics could allow for such a phenomenon by which the mere presence of something hidden is communicated to a held object, irrespective of the material composition of the artefact and the detector. The closest scientific leap one can make is to the metal detector. Such an apparatus works not because it communicates with alleged spirit guides but because of the electromagnetic properties of metals. Similarly, de-mining efforts can capitalize on the metallic composition of some mines as well as to the smells of the explosives themselves, which is why trained animals such as dogs can also be used in these situations. But can underground water affect the movement of metallic rods?

The claims, already dubious, are stretched even further when one learns of map and information dowsing as alternatives to divination in the field. This involves gathering information about a piece of land potentially miles away using a map proxy. And information dowsing? Think Ouija board. You ask any question to your pendulum and it answers back. Don鈥檛 believe me? An article once published by the American Society of Dowsers, , claims you can divine your workout schedule this way. The author writes that they ask their pendulum the following questions: should I exercise for fewer than 90 minutes today? should I work out for fewer than 60 minutes? should I not work out today? The author also reminds us about 鈥渄owsing your supplements and dowsing your protein intake for maximum muscle gains.鈥 Why hire a professional when you can rely on the movements of a pendulum?

Just a bit of harmless na茂vet茅, one might say, but what if dowsing was promoted in healthcare? It appears that some dowsers, not content with divining for water, can now ! Meanwhile, the Canadian Society of Dowsers seemingly , drawing connections between divination and pre-scientific notions of qi and prana and the esoteric art of healing known as Reiki. If you鈥檙e ready to believe that swinging a pendulum over a map can find a missing person, it鈥檚 a tiny sidestep into thinking it might just cure disease.

But pulling back from these ridiculous claims for a bit and putting aside the question of just how it would work, does the basic practice of dowsing for water work?

This is where we need to visit a barn.

鈥淎 misuse of public funds鈥

They are often known as .

Done over the course of two years in the mid-1980s and to the tune of a quarter of a million American dollars (invested by the German government), the experiment tested 500 dowsers in a barn outside of Munich. Many dowsers believe that what their rods or pendulums are picking up on is a form of radiation, and this radiation could be harmful to our health. Thus, the German government wanted to prove that dowsing was real so that these dowsers might be useful in better understanding this type of radiation. How they went about testing these dowsers is fascinating. It involves a two-story barn.

On the ground floor of the barn (or Scheune in German), imagine a 10-metre line on which a wagon can ride back and forth. On the wagon rests a short pipe hooked up on both sides to a hose. From above, this would look like a cross made up of the 10-metre line and the hose. The idea is to move the wagon to a random point along this line and to turn on the water, which will start flowing through the pipe. Of course, if the dowser is on this floor, they will know where the flowing water is, which is why the dowsers were instead taken to the second floor of the barn.

On this top floor, the 10-metre line is duplicated. The wagon below is moved to an unknown location along its line. Water starts flowing. On the floor above, the dowser must use their skill to figure out exactly where the wagon is along the line.

This set-up was further cheatproofed by being inspected by a professional magician beforehand and by having the position of the wagon in each test be randomly picked by a computer on the spot. These trials were also double-blinded: neither the dowser nor the researcher standing next to them knew where the wagon was during the trial. Even so, there were issues that could have helped dowsers along, such as the possibility that the sound of water turbulence coming from the floor below could have been picked up by the dowser. But this would only have helped the dowsers look more proficient than they were, and since dowsers have often explained their duds by the nearby presence of skeptics, the fact that both the German government investing in the Scheunen trials and the experimenters in charge of them professed a belief in water witching meant that dowsing was primed to prove itself once and for all.

But it didn鈥檛. In the much looser early trials, which were not even double blinded, 457 of the 500 dowsers were eliminated since they did no better than chance at finding where the wagon with the running water was. That鈥檚 a little over 91% of the test subjects. The remaining 43 dowsers were submitted to a total of 843 single tests inside the barn. They would come back on separate days and try it again, and their predictions as to the location of the water running through the pipe was recorded, as was the actual location of the wagon. When , you see that the totality of the guesses made by the lucky 43 over the course of their 843 tests is a random mess. Six dowsers did really well in one series of tests, but when they were brought back for another series, they did no better than chance. Given the number of trials performed and of individuals tested, some of these dowsers were bound to do well in one test by chance alone. They could not, however, reproduce their results.

The Americans were smarter than the Germans: their Geological Survey had that further testing of dowsing 鈥溾 would be a misuse of public funds.鈥

I can already hear the protests from people who have first-hand experience of dowsing successfully finding underground water. The answer is that, in a manner of speaking, dowsing does work.

Lessons from the past

That same U.S. Geological Survey which had declared dowsing a relic of the past a century ago has, on , a very prosaic explanation for the success many people have bringing dowsers onto their land to help them find the perfect spot for a well. 鈥淚n a region of adequate rainfall and favorable geology,鈥 the website states, 鈥渋t is difficult not to drill and find water!鈥 Therefore, dowsing will help you find water, but so will avoiding the services of a dowser.

As to how a dowser鈥檚 rods or pendulums behave as if responding to external forces, the answer here is also simple: the ideomotor effect. In short, suggestions and expectations can trigger muscle movements which bypass our will. Thus, while we are responsible for these twitches, it feels as if we are not. It鈥檚 the same effect at work when playing Ouija and resting our fingers on its planchette: our desire for answers triggers minuscule muscle contractions in our fingers which are not willed by the executive centre of our brain. Thus moveth the planchette. Thus moveth the rod. We have known about this for two hundred years. Small, driving movements of the body and arm . You don鈥檛 need to be a grifter for your pendulum to find water; self-deception is enough.

Belief in dowsing may seem innocuous but it has actually claimed lives. In 2010, BBC Newsnight reported on exported out of Great Britain and into countries such as Iraq, Thailand, and Kenya. When one of these so-called bomb-detecting wands was disassembled, it was shown to be an empty plastic casing. No functioning electronics were present; rather, it was a plastic handle with a metallic rod that could swing left to right. It was essentially a dowsing rod, primitive and utterly useless. People died because such an instrument failed to detect roadside bombs.

Now, with global warming, dowsing is bound to attract the attention of people trying to survive droughts. The modern skeptical movement cut its teeth on this sort of paranormal thinking, from dowsing to alien visitations to the Satanic panic of the 1980s. These topics may seem quaint by today鈥檚 standards, when pseudoscience has become more refined and harder to debunk, but we should not forget the lessons we have learned from these skeptics. The Satanic panic has been transubstantiated into the Save the Children campaign of QAnon. UFO conspiracy theories have infected . And dowsing? A village in France is training people in water witching, calling it and both and have been reported as making use of these divination services.

Those who do not learn from history are doomed to repeat it鈥 and waste their money in the process.

Take-home message:
- Dowsing is a debunked technique for searching for underground water or other things using the motion of a held object, like a stick or pendulum
- The movements of the held object are actually created by tiny, subconscious movements
- Despite the fact that dowsing has been shown time and time again not to work, dowsers continue to be employed, most recently to help find water following climate-change-related droughts


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