The most recent submissions are listed first.
| Digest Nr | Subject and Author |
 |
| 2009.04.20.05 | Early Ampico A With Piston Crescendo Mechanism, from Charles Moen |
| 2006.06.21.06 | Unknown Piston Airmotor is Gulbransen, from Eric Shoemaker |
| 2006.06.19.04 | Unknown Piston Airmotor, from Randolph Herr |
| 2005.08.14.11 | Boyd Pistonola & 4-tier Gulbransen Piston Airmotor, from Bruce Mercer |
| 2005.08.13.05 | Boyd Pistonola & 4-tier Gulbransen Piston Airmotor, from Donald Barton |
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