As always, when Art Reblitz has something to say in this forum,
you can take the information to the bank [080828 MMDigest].

The J.C. Deagan Company of Chicago also marketed a set of electric
bells operated from a keyboard.  These were strung around the walls
and played during performances.  These were a flash in the pan,
and relatively few were ever sold.  Or, at least I have not seen
much mention of them in film trade journals of the second decade
of the 20th century.

I really can't imagine anyone watching a film if the bells were
even remotely as loud as those in a Una-Fon.  Probably, they were
more softly voiced.  I have a photograph of a theatre with such an
installation.  Harvey Roehl's foundational book, "Player Piano
Treasury", has a nice Una-Fon advertisement.

Dave Bowers