[ First published in 170217 MMDigest, photos added 8 Sep 2017. ]

Bernt Damm (in MMD 170216) came up with a novel theory about the
unusual Steinway upright Duo-Art I wrote about in MMD 170214.  He
posits that, in the absence of a Rewind pneumatic, the tracker bar
Rewind hole, whose nipple shows clear evidence of having been connected
to _something_, might have been tee'd into the switch cut-off trigger
tube.

Certainly, this is a "fail-safe" solution to this configuration, by
bringing the machine to a halt at the end of the music.  The owner
would have then had to manually shift the mechanism into the rewind
position and turn the motor on again, but this would have been much
preferable to having to repair a roll ripped from the supply spool.

However, the owner could also expect to have one or more "spurious"
cut-off events during rewind as any slight leakage at the rewind port
would have caused a motor cut-off rather than a simple additional push
of the shifter into the Rewind position.

As noted in the original posting, there is no hole in the take-up spool
as indeed, I have never seen such in any Aeolian plated metal take-up
spool that I have encountered.

( Added later -- )

Additional details of the Unusual Duo-Art [MMD 170214] have come to
light.  First, I misspoke about the orientation of the keyslip levers.
They operate in sliding fashion in the horizontal plane; they are not
vertically oriented.  The "long" tracker pneumatic is actually 9" long,
not 8" as previously stated.

Not only is there no rewind pneumatic, there is no Motor Cut-Off port
on the tracker bar, a detail I had previously overlooked (see attached
photo).  This leaves the only possible connection of the tracker bar
rewind port as the switch cut-off pneumatic, confirming the conjecture
by Mr. Damm.

I also include photos of some other markings including the serial
number with "V/R" notation, a stenciled number that appears at the
upper right of the cast plate, of unknown significance, and some
numbers cast into the plate at its lower right extremity, behind the
pump.

John Grant

 [ http://www.mmdigest.com/Attachments/17/09/09/170909_193155_Unusual_Dou-Art_5.jpg 
 [ http://www.mmdigest.com/Attachments/17/09/09/170909_193155_Unusual_Duo-Art_6.jpg