I'm not exactly sure of the difference between a "Rueckenklavier"
and "Walzenklavier", but the former seems to refer in this case to
a "laterna", a portable barrel piano made in Constantinople and a few
other places and played in the Middle East, especially Greece, Egypt
and Turkey.

These have interchangeable barrels and are traditionally accompanied
by live percussion (a large tambourine).  Their music is popular
Turkish and Greek melodies.

I have a nice CD of laterna music on the EMI label.  The title is in
Greek, but the number on it is 7243 8 34835 2 5.  The title is "NIKOE
APMAOE, AATEPNA KAI NTEOI" (the "E" and "O" are not like our's).  Each
tune is played several times with various rhythmic accompaniments to
good effect.  I own a laterna which was on display at the old Musical
Museum in Deansboro, NY.

Philip Jamison
West Chester, PA

 [ Found at http://www.studio52.gr/grin_nm.htm and
 [ http://www.studio52.gr/info/8348352.htm :
 [   "Nikos Armaos: Laterna Kai Ntefi"
 [   Company: Minos - EMI
 [   Release Date: 1977
 [   Code: 724383483525
 [ -- Robbie