John White wrote:

I was deeply skeptical before I saw it done. I don't know HOW it works
and neither does my friend, but it certainly does.

It doesn't. http://www.randi.org/library/dowsing/

If your friend can demonstrate the alleged ability under scientific
conditions he is up for $1,000,000.

If he cracks that I'll sell my house & add £200,000 myself.

--
Dave
The Medway Handyman
www.medwayhandyman.co.uk
01634 717930
07850 597257