]"The human mind is capable of so many things we don't quite fully grasp yet"[/quote said:
Yes. Like believing that dowsing has any scientific basis. Incomprehensible.
Thinking that something might be lost under a truck seat and then finding something lost under the truck seat is the power of reason. The likelihood was better under the seat than elsewhere. I used to find coins under the food racks in our small-town general store. It was a reasonable assumption that coins would roll there - and so they did. If I had used a coat hanger to find the coins it wouldn't be any different - just me influencing the wire subconsciously to get the results I already suspected were there.
Should a plumber already suspect, based on observational evidence, where the sewer line should be, it is only once removed to subconsciously (or consciously) make your dowsing wire respond to your intent. This is exactly how dowsing 'works' - people respond with their body to the expectation they have formed, based on prior knowledge and experience.
Real scientific tests have shown so-called 'professional' dowsers using their hips and arms to influence the wire. Why? Because they were subtly influencing the wire to correspond with their expectations. When they were required to find a buried item to which they had no prior knowledge and experience (they had no idea where it was hid and couldn't use their experience with plat maps to guide them as a plumber would), they couldn't find it.
These tests have been repeated ad nauseam and no dowser has done anything close to identifying the correct spot. They later claim blocked energy and such, but the whole thing is a scam. Sadly the dowser may truly and sincerely believe it can work, buying into some theory of hidden dowsing power or mental energy (people are fooled every day into believing things that make no sense).
As to two rods crossing when near an exposed object ... tests again show that as the dowser neared the target they bent forward ever so slightly, which allowed the rods to dip forward. Some would drop their wrist a fraction of an inch (can be seen on tape) to allow gravity to pull the rods together. Again, it is only necessary for the dowser to relax and let their involuntary muscle control react to the impulse from their subconscious. It isn't magic or scientific principles - other than psychology - it is really just at the level of a party trick, and nothing more.
If you want to test your dowsing ability - have someone hide a coin in a field without your knowledge. Then have the dowser find it. But the person that hid it cannot be present (turns out that even then the dowser picks up clues from the person who hid it by how they react - all subconsciously). The dowser will fail every time.
The spot the dowser picks will coincide with what seemed most logical with having the highest probability to the person holding the dowsing rods of yielding success. This is equivalent to a 'hunch' but is really based on experience - the dowsing rod is just another way of confirming the 'hunch'. In reality the dowser is subconsciously looking for signs of a recently dug hole (power of observation at work) or imaging where they would hide the coin (experience at work). The dowser could just as easily walk around the field empty handed and then finally stop and say "I think it feels like it should be here", without the dowsing instruments. They'd still be wrong but the rods crossing or dipping (on command) just make better theater.
Johnnyanglo