(based on information from Canadian Society of Dowsers web article by by Walt Woods and Mardi Gieseler)
We may not know everything we need to know right now about how dowsing works, but that does not mean that we should not continue to test or experiment with this practice. Many things that seemed superstitious hundreds of years ago are quite common place now. For who knew you could really keep a small fire in a glass bulb going all day long and turn it off and on by a mere flip of a switch? That must have seemed mystical. What we do know is that dowsing has been used for centuries and many have claimed that it is a reliable system of finding water, oil or even treasure. So, you may be asking at this point, who besides snake oil salesman really use dowsing? Surely no one of importance.
This is where it gets interesting. Though officially the government has denounced dowsing as a discredited method of locating water, it has been documented that the US Military has indeed practiced dowsing. In the Vietnam War for example, US Marine engineers used dowsing to locate tunnels, booby traps and other hidden enemy stockpiles. In fact, the Marines enlisted the assistance of Louis Maticia to run the dowsing program and teach the engineers how to dowse. (NY Times, Oct 11 1967). Prior to this, General Patton was also known to have used dowsing to locate fresh water for the US troops as German soldiers would blow up any wells when retreating to try and keep the troops from having access to water.
Many government agencies including the Bureau of Land Management, the US Soil Conservation and the National Park Service were all known to dowse. And, it wasn't only government agencies. Many large corporations also have used dowsing in their line of work. According to the Canadian Society of Dowsers, both pharmaceutical and big oil companies have used professional dowsers to locate water and oil for their use.
I do like a quote attributed to Albert Einstein (unknown if he actually said it, but I can appreciate the meaning), "I know very well that many scientists consider dowsing as they do astrology, as a type of ancient superstition. According to my conviction this is, however unjustified. The dowsing rod is a simple instrument which shows the reaction of the human nervous system to certain factors which are unknown to us at this time”…..The most fantastical machine we still have no full understanding of is our own mind and body. I prefer to think of dowsing rods as an extension of our untapped cognitive powers to detect, however small, differences in our environment. I don't think the rods are magical, I think our own minds are.