If you are good at it. :-) 

 I use to do it to train myself, though instead of giving myself just a
50/50 chance (red or black) I used the symbols they use for testing
psychics--square, triangle, circle, wavy lines.  I made up a set of cards
for myself, multiples of each, and would dowse each card.  Kept track of
whether I was right or wrong.  Got to the point where I was more right than
wrong.  

samala,
Renee
www.eamega.com/RPainManageEnt 
Chronic pain does NOT belong in your body.  The Am Wand helps 
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-------Original Message-------
 
 
Bodhi, what are the limitations of this dowsing/calibration?  For example, 
could it be used to determine if a faced down playing card is red or black?