While not necessarily "mechanical music", the steam calliope was an
important part of the classic Mississippi steamboat.  Those of us who
grew up along the Mississippi River, especially in St. Louis and New
Orleans, may remember Streckfus Steamers Inc. and their two mammoth
excursion boats, the SS Admiral and the SS President.

Both these boats had steam calliopes which were played during the
trips.  Both boats were still steam powered side-wheelers until the
mid 1970s at which point they were converted to diesel with propeller
drive.  Suffice to say the calliopes were no longer steam either.

The Admiral was taken out of service in the early 1980s and is now
a casino on the St. Louis riverfront.  The President was in New Orleans
until the mid '80s when she was moved to St. Louis (actually her home
port prior to 1940) and ran for a couple years.  I was lucky enough to
work onboard her during my summers and became very friendly with the
chief engineer and I remember him showing me the disassembled calliope,
about which he constantly remarked, "I really need to get around to
putting that back together."

I believe the passenger steamers Delta Queen and Mississippi Queen
which run along the river and the Ohio on cruises have calliopes as
well.

Best to all,
George Glastris