An article in 030404 MMDigest asks about the tubing connections to the
hand controls of a Norris & Hyde Air-O-Player system.

I found a 1917 drawing of the Air-O-Player piano roll tracking mechanism
that uses hand operated push buttons located at the key slip to operate
pneumatics that shift the music roll laterally and also lock the
position of the shifter.  The drawing and its accompanying text is
at the MMD Tech site, http://mmd.foxtail.com/Tech/

Robbie Rhodes