This effect dates back to 1827. After being unseen for some decades The Great Carmo reintroduced it in the UK c. 1932 and it is still often referred to as the Carmo Beads in the UK. The rights to Carmo’s was purchased by Davenport’s from The Great Carmo c. 1938 and they marketed it at The Great Carmo Bead Mystery. This did not stop U.F. Grant releasing it as The Arabian Bead Mystery c. 1939 and it became a pet effect of Jay Marshall. John Fedko re-titled it as The Beads of Prussia and that is the current term in the USA.
Sam has created a very nice quality one with sold plastic beads and tube. The gimmick also works very well.
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