The Illinois 21 Jewel 3/4 plate c. 1923, a fine grade Railroad Watch, especially ornate with polished gold screw heads and regulator. A very robust timekeeper, with simple well engineered lever set works.
This example was in fine shape. The ceramic dial had no cracks, and the hands were in very nice condition.
After a cleaning and some adjustment the positional errors in six positions is great. The timing machine shows -5 sec/day in all six positions with 5 seconds of instability. But in reality the most common positions (stem up-left-right, face up) will bring it closer to 1-2 sec/day.