Just read about this at Rene Rondeau's site:
http://www.edisontinfoil.com/biophone.htm
What an interesting device! I never knew it appeared in
My Fair Lady (although I've never seen it outside of the odd 5 seconds of it when I'm flipping channels, and besides, I don't really scan movies intently for phonographs

). Someone should go though those old prop dept.'s or inquire about it sometime (anyone here have access to that sort of stuff?

)... I do remember this one movie about a professor who tried to take a trashy British woman and turn her into a charming, polite girl that had lots of phonographs and gramophones used for elocution and dancing lessons. Can't recall the title, though
Any chance of a video demo, Rene (if you're on this board)?