There has been interest recently in a thread of Mechanical Music 
in the Movies.  I have authored two articles on this subject and 
would be happy to provide any MMDer with a PDF copy of either 
or both.  They are

(1) "Mechanical Music in the Movies", Musical Box Society 
International "Journal", Autumn 2004

(2) "Mechanical Organs and the Motion Picture", Carousel Organ 
Association of America's "Carousel Organ", July, 2014

Please send requests to me at bopp@peoplepc.com.geentroep 
[delete ".geentroep" to reply].

Ron Bopp