Above is the movement, but this time, seen from the dial side. The peripheral winding rotor, as well as the module for the automatic winding train, have both been removed, and the mainspring barrel, as well as the going train, have been removed too, leaving the tourbillon, for now, in place. The cage is driven on its periphery as well, and inside the lower circular assembly (which is not a bridge, as it does not support or cross over the tourbillon cage) you can see the inward facing teeth of the fixed fourth wheel, which gears to the escape wheel. As the cage rotates, these teeth mesh with the pinion of the silicon escape wheel, driving it; the escape wheel in turn transmits energy to the lever escapement, and the balance.
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