MMDer Bill Ryan (flix@cellone.com) just wrote me that he is coordinating
a new research project:

  "We are starting a sale/wanted/search service for Edison cylinders
  (Blue Amberola and such, two- and four-minute) to make a directory
  and research listing of these.  [Also] the coin operated Amberolas,
  etc., and especially their horns."

Bill said that he will write more about this project later; this is just
the 'advance notice'.  He said he is also "deep in the writings of the
history of the movie palaces of Upstate New York and Western
Massachusetts."  ... Never a dull moment with Bill !