English fusee drive

English pocket watches often use a mechanism called a "fusee" as part of the mainspring to improve the powering of their watches.  The fusee is a cone shaped object which is used to wind up a tiny chain attached to the outside of the mainspring barrel.  This allows the spring power to be more even over the mainsprings use by compounding the springs effect as it unwinds.   In the photos you will see the fusee and its parts, which need to be serviced in order to maintain the integrity of the watch function. This additional work and the care of the tiny chain will make the repair and cleaning more complicated and expensive.  The chains are typically .6mm wide .3mm thick and about 6 inches long. The inner parts to the fusee are designed to allow fusee cone to turn in one direction only.  The fusee often includes a spring to allow for maintaining power while winding.