The first three photos show the movement and remontoire. All of the original arbors were square in profile while the retrofits circular. The new third wheel attached to it's arbor retains the original lantern pinion. This would have been attached to the original escape wheel arbor whether this was with a crown or anchor escape wheel. Although the arbor is circular it terminates in a square to fit the original pinion's hole. This pinion is attached to the rocking frame making up the remontoire. Normally a rocking frame remontoire has a very short period - typically 5 to 10 seconds. This is necessary as a longer period would result in too far a swing for the rocking frame causing the pinion to leave the proper meshing position on the wheel it engages. In this case the wheel and pinion are large and the tooth profiles coarse; allowing for the longer 20 second period. A smaller clock with finer wheels needs a shorter period as seen here.

The fourth photo shows the old style stirrup click system used in both main wheels. The helical tooth- cut wheel (last photo) has the conversion date and maker's name. This too is mounted to an original square arbor.