In regards to a 'Regina nickelodeon', what the inquirer might be
referring to is the roll operated 'Regina Sublima'.  This uses
a rather large roll on a reiterating hammer action to play piano
strings, creating a mandoline type effect.  The following link will
take you to five videos demonstrating this instrument:

  http://www.youtube.com/results?search_query=regina+sublima 

Dale F. Rowe