We have searched and searched for the history of the "rola bola" and can find nothing. In case you are not a circus afficianado, rola bola consists of a board, with stops beneath, on a cylinder, on which one balances (or falls). It is an excellent exercise for the back, for improving balance, and for having fun. No dictionary or word compendium of any sort, so far, has provided any official information. Can any of you? Or can you site a source? Thanks very much. BJS