Dear Ron, I'm delighted to hear that you are still in the paddock and haven't given up on the marsupials. You might like to inform them that the original patent was May 14, 1872 number #126848. But it didn;t stop there. Since that time no less than two score piano designers have made their own duplex scales some of which, such as Fazioli and M&H , have most interesting variations. Apparently the duplex scale is not a dead issue but is alive and "hopping". Duplexdan
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