Got the photos! First of all the piano is a "Themodist" style of player. The two elongated holes, like hyphens, are connected to Throttles on each side of the "stack"; the pneumatic stack is divided into bass and treble. Themodist rolls (Aeolian Co.) or Angelus rolls (Melodant, solodant...I believe) have holes shaped like snakebites or quotation marks in the rolls when that horizontal line of notes or a single note is to be accented. The lever on the keyslip on the left is held to the left, lowering the playing level of the piano to a set level. When a snakebite appears, that half of the piano is accented. The two buttons are most likely attached to the same tubes as the snakebite tubes, so you can manually express non-Themodised rolls. The Metronome lever is used to control the tempo on these special rolls, that usually have a red line to follow, adjusting the constantly changing tempo. The tube in your photos would most likely supply vacuum to a device like the theming pneumatics. Look for one on the right side of the piano, I believe I see one. At first I thought it might supply an automatic sustaining pedal pneumatic, which it might, but I don't see it. I do see a manual sustain pedal hand lever in the keyslip. If there is a pneumatic connected to the sustaining pedal trapwork or linkages, it could be its vacuum supply. 99.9% of American pianos that have an automatic sustain (connected to the large hole on the left of the tracker bar) have it on the left, bottom of the piano. Yours could be up higher where I can't see it. It might be missing, too. If that is the case the hole can be plugged, awaiting future repairs. The player pianist can use the manual sustain lever. Look for a footprint or shadow of the missing mechanism. Hope this helps! Berley Antoine Firmin II
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