Barrie, I read your post concerning patents and other stuff with great interest. I suppose You have the Olivier Barli book " La facture Française du piano de 1849 à nos jours" contains short description of all the patents from 1849 to 1983. Other references in this book wich was a graduate work (musicology) - 405 pages ed La flute de Pan - Paris 1983 - may be still avaible - I had mine from these not so old days. Best regards to England Isaac OLEG Piano Technician Paris
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