Years ago I worked with a chap whose family farmed in Ireland. When they needed to dig a well they had no success with the drilling company so got an old lad with his dowsing rod who proceeded to find a suitable spot. They sunk the well successfully. The story is apocryphal of course, but I can't see why he'd lie to me.

I have no idea if there's any empirical evidence for the efficacy of dowsing, so I'll keep a skeptical but open mind.

As an aside, anyone interested in English Eerie who hasn't should check out the work of the late Tom Lethbridge, who wrote the definitive work on the subject, 'The Power of the Pendulum'.