I congratulate Ana Gerard on her acquisition of a fine "parts"
Weber Grand.  However, I'm surprised at the lack of a una corda action
from the player's pedal.  My own Weber, built 1925 or '26 judging from
its features, has a true una corda pedal action that uses the center
quick-disconnect block as part of its linkage.  (But unlike some
Steinway Duo-Arts, my player action just lifts the hammer rail as in
an upright).

I also have a full Sostenuto action, not the bass sustain found in
uprights.  My serial number is 76198, if anyone would like to check.

It's clear that 1925 through the early 1930s were major transition years
for Aeolian, with all sorts of changes coming in rapid and random
order.  So maybe I'm not surprised by anything I read here!

Pervious postings by others made the point that in a reproducing piano,
the hammer rail lift is actually more useful than a roll-driven una
corda shift -- mostly to allow the player action to play softly but
rapidly and reliably, something we humans have to work very hard at
too!

As for the sustaining pedal, I can't imagine a piano without one
for the human player.  Without it, you can play only harpsichord,
clavichord, or manual organ music.  Any piano compositions (excepting
maybe Mozart) will sound like Chopsticks.

However, this pedal is terribly abused.  I once threatened to
remove and hide the pedal linkage before a chorus concert, where our
accompanist basically lifted the pedal after every other measure,
whether the music needed it or not.  :-)

Mike Knudsen