Hello!  Ray Fairfield wrote about the Smith Lyraphone Pneumatic Power
Roller Push-Up Player (MMD 031204):

  "The interesting thing about this tracker bar is that there are
  four distinct (and different) hole widths.  The width of the holes
  that play the notes does not vary throughout the scale. "

Same thing on the Needham Paragon push-up player, which is a pneumatic
instrument, but whose roll mechanism is driven by a clockwork motor.
It has a very beautiful holly (?) tracker.

I have only seen a single specimen of the Needham Paragon, in a state
which Arthur W.G.J. Ord-Hume (author of "Player Piano") would have
described as "blatantly deteriorated."  The case was almost eaten up
by woodworms, but they hadn't touched the holly tracker!

There may have been Swedish power roller player mechanisms, too,
such as the two-shoe (!) Nystroem recorder-reproducer (covered by
half a dozen Swedish patents).

Christofer Noering
Stockholm

 [ Read about mechanical musical instruments with a power roller at
 [ http://mmd.foxtail.com/Pictures/PwrRoller/index.html  -- Robbie