Hi John Tuttle and MMD,  Thanks for everyone's interest and help.
I will answer John's questions in order where I can.  Bob Stout can
probably answer the ones I can't as he worked for a company years ago
that was a dealer for these instruments.

1. This instrument plays half "O" rolls, i.e., regular Play-Rite "O"
rolls have been divided in half with 5 to 8 songs on each roll and
mounted on standard large regular player piano (88-note) spools.

2. In addition to the piano this instrument plays bass drum,
snare drum, triangle, wood block, tambourine, cymbal, xylophone and
a rinky-tink doodad.

3. Lock and Cancel -- I'm going to refer this one to Bob Stout.

4. It takes quarters but the coin mechanism has been disconnected.

5. I believe the various sequences are controlled both electrically
and pneumatically.

Now for the most recent revelation.  After a couple weeks of
experimentation this morning I discovered the correct sequence of
button pushing that will complete the reroll with no gnashing of gears.
When the roll has stopped with a few turns of paper remaining to
reroll, turn the toggle switch on the right to "Off", next press the
"On" button once and lastly hold the reroll button down continuously
until reroll is complete.

Now the obvious question: Why doesn't it reroll completely on the first
reroll sequence?  The only explanation I can come up with is that when
it reaches the stop point it starts to play again, and, since these
Universal nickelodeons were designed for commercial operations, it
would have been desirable for them to not completely reroll.  It would
then be ready to play again without the operator needing to start it
all over again.  Perhaps this is a function linked to the coin op
mechanism, i.e.,  multiple quarters would get the roll to play multiple
times.  Just some thoughts.

Musically,
Tom Huchinson

P.S.: All the Perflex pouches were replaced several years ago.