These movements, as pictured on p498 of The Complete Price Guide #26/ 2006 ,have what appears to be an adjusting screw of small head diameter , like a detent screw, below and to the right of the crown wheel. I saw one recently with a hole where the screw had been. It went through the bridge and pillar plate and ended near the setting, wheel which transmits power between the clutch weel and the minute wheel. The hole was not threaded or chamfered, so was not for a bridge screw. It was probably an adjusting detent of some kind . The regular setting detent WAS present and worked. Can any one tell me what the missing item is and what it does? Many thanks, JJW
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