I am most pleased to hear that the Edison cylinder phonos were 4" and
not the 5" that I stated in my little story.  I knew they were longer
so as to match the running time of the film reel, probably 1,000 feet.

I got my information years ago from Art Shifrin, who is the man that
made the synchronizer and put the films and sound together in sync on
video -- probably for the first time in history!  I am sure I was
thinking about the Concert cylinders when I mentioned 5" cylinders.
Shifrin states 4-1/4" diameter by 7-1/2" long, and 100 grooves per
inch.  I should have re-read his story.

Thanks gentlemen, I would not like to be the one putting out false data
on this fascinating Edison adventure.  By the way, Shifrin wrote a very
detailed account of his work in "db magazine", December 1982, pages
30-37.

Jim Crank