According to Taylor and Rogers, Jerome was one of the most prolific makers of 8-day movements. Their NAWCC Bulletin Supplement (#19, Eight-Day Wood Movement Shelf Clocks–Their Cases, Their Movements, Their Makers) identifies the movements of 8-day wood works makers.
Type 4.23 8-day movement, with metal winding drums.
Type 4.112 8-day movement with brass bushings (original). Although only the winding arbor bushings are visible, the movement is bushed throughout. This movement was made, in part, with gears from 30-hr movements. A spacer block is attached to the back plate to accommodate the shorter arbors of the #4 and #5 gears in the time train.