Modern dowsing devices... take your choice!

Traditional (16th Century) dowsers used a forked stick!

The most popular dowsing rods today; you can buy them from Walmart!

A lovely example of the essentially magical basis of all dowsing is that almost every dowser claims to be able to dowse as well from a map as they can by being actually on-site. The map does not need to be an official map, a hand-drawn sketch will do. In fact recently dowsers have found that they can dowse "just as well" from images provided by Google Earth on their computer monitors! Dowsers who claim to be able to find lost pets begin their efforts by "dowsing" a photo of the missing pet! It could not be more clear that we are dealing with claims that could make sense only in a voodoo universe, where representations are magically equivalent to the thing itself.

Remarkably, a decisive scientific test of dowsing was conducted in the 17th Century by Athanasius Kircher (1602 – 1680). Kircher was a remarkable figure, with seemingly endless curiosity about the world around him. Hearing about the feats of dowsers, Kircher found an expert dowser who agreed to take part in a simple test. The dowser, using the usual Y-shaped twig of the era, tensioned it precisely as required to obtain perfect results. While the dowser held it in the correct position, Kircher nailed the ends of the twig to a long board. The dowser was then asked to dowse by holding the ends of the board. Famously, such a Y-shaped dowsing rod dips visibly when something desirable is sensed. But although the rod attached to the board was perfectly free to dip, when the dowser walked about, it never dipped... in fact it remained  rigid. Kircher wisely concluded, "There is no such thing as dowsing... there are only dowsers." Many scientific tests have been conducted of dowsing in the centuries since Kircher. The result, where dowsers were actually tested instead of just allowed to perform, was that in every case, dowsers performed according to pure chance. Here's a description of a long study conducted by the German government.  So, how does dowsing work?  If a "mysterious force" strong enough to bend willow twigs was involved, physicists would have been studying it since the 17th Century... there is definitely no such force.  The bending or swinging or oscillating of the various dowsing tools is a result of the fact that they are chosen for their ability to amplify tiny motions of fingers, hands or wrists. These motions are often unconscious or semi-conscious, and are easily detected and studied by psychologists and physiologists.  Group versions of the same basic phenomenon are seen in the 19th Century Spiritualist fad of table-tipping, and in the fortune telling toy called the Ouija Board.

Note these two dowsers use totally different Y-rod grips!