If you take a look at the pictures on Mike Meddings' wonderful
DoctorJazz website, you can see Cook at two quite different marking
pianos.  We spotted this some years ago when Mike was putting the
material together, and also noticed that many sources mis-attribute the
photos, randomly assigning them to QRS or Aeolian American.  There is
no need for this muddle, because it's quite easy to tell the two apart.

There are several well-attributed pictures of Cook at Imperial
Industrial Co. in New York (QRS).  These show a piano having locking
levers above the keys.  This piano is still at QRS in Buffalo.

    http://www.doctorjazz.co.uk/jlcjslg.jpg (1962, Jack Shaylor)
    http://www.doctorjazz.co.uk/dsjlc3.jpg (1949, Duncan Scheidt)

There are also photos taken at Aeolian American, which show a piano
having two complete keyboards, the upper of which is tilted down.  This
is clearly the same piano as in the recent eBay auction.  The eBay
description is therefore plainly wrong, because it isn't the QRS piano!

    http://www.doctorjazz.co.uk/jlc0668b.jpg (late 1960s, NY Daily
    News)

The really interesting question is, Where did the Aeolian American
piano come from?  There must have been many of these devices in use
within the industry, and Cook could quite easily have picked up surplus
equipment for home use at any point from the late 1920s on, as all the
other operations closed.  It could have come from absolutely any other
company besides QRS!  It's really only a museum piece now, because it
is infinitely easier to master rolls on the computer.

Julian Dyer

 [ The complete photo gallery at the Dr. Jazz website is at:
 [ http://www.doctorjazz.co.uk/page4.html        -- Jody