Regarding the correspondence on restoring Mission Oak (or any other
genuine French-polish) finish.  Be _very careful indeed_ if wiping
a cloth soaked with  de-natured alcohol ("methylated spirits" in the
UK) over an original surface.  This is because, here in the UK, from
the 1910s to the 1960s, every house had coal fires, and everybody
smoked.  All those smoke particles will have been lovingly wax-polished
into the piano surface, over many years.

The danger is that your rag could end up re-dissolving the shellac
and rubbing the grunge back in!  "Re-amalgamation" is sometimes
suggested, but it's a short-term fix.  At least, try a test area on
the back of a leg.

Paul Collenette
Devon, UK