The gem unlocks his power.
When the load to be weighed comes upon the platform, the end of the steelyard rises and unlocks the ratchet wheel through the pawl; the sprocket gearing is driven by the friction clutch, and drives the axle of the left-hand small pulley.
This function locks the runnable object while removing the callback and unlocks it when done.
Birch veneer laminated drawers give the cabinet a gentle impact whilst opening the drawers unlocks the mechanism of their support, creating interest.
This upgrade increases usable mid band torque and unlocks more of the engine's potential without demanding further upgrades to supporting systems.