Priestess,
Thanks for your reply :) By biro casing i meant the plastic outside of a ball-point pen - presumably so the rods will spin around freely as opposed to being clutched in someone's sweaty palms. Apologies for any confusion with the erm, language barrier! Thanks for helping me re-establish the line between reality and dreamworld! LOL.
I've heard of dowsing pendulums being used by surveyors for checking what underground pipes are for, but they're not 100% accurate and not regarded as an 'oracle' of information.
Happy hols to you too :)
Take care.
Graham.