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The application of body and armonium or only one of these instruments to a piano, manual or mechanical, forming a single unit with piano or two or more differentTogether or apart from the piano, and operate the valve plug of the notes
The application of body and armonium or only one of these instruments to a piano, manual or mechanical, forming a single unit with piano or two or more differentTogether or apart from the piano, and operate the valve plug of the notes
