I came across something I had forgotten I had and where I picked them up. A small decorative box with two cloisonne balls over one inch in diameter which are decorative and softly musical when picked up. Did this come from a garage sale?
I recognized what they were immediately - geisha or ben wa balls. They are gently inserted into the vagina and the woman should rock or practice squeezing them. They are excellent for developing love muscles, kegel exercises, and can give heightened arousal or orgasms for hours at a time. The lazy geisha (pdf) of course writes about hers.
Kegel exercises were originally developed as a way to increase bladder control for women without surgery and have a controversial history. Doctors prefer surgery and were reluctant to talk about improvements to sex.
Another site says I have Chinese meditation balls, you roll them around and actually try to avoid the musical chimes. The ones I have look a little like this but a bit nicer. Really looks like that is it, my female expert(?) says she has only seen that size as hand exerciser and meditation devices - although the hand exercise can serve a useful purpose in sex.
