Adjusting of the moon disk with clocks.
- The figures in the moon disk from 5 till 29 1/2 represent the number of moon days. The moon disk is automatically moved by the clockwork and indicates the phases of the moon.
- The moon disk can be adjusted by pushing it with the finger slightly to the right. Each tooth that the disk shifts is a so-called "moon day".
- The number 29 1/2 is new moon and 15 full moon. There in between lies the first and last quarter. Put the number 29 1/2 in the middle of the half circle being new moon. One counts the number of days from new moon till the day on which one starts the clockwork on the calendar and shifts then the moon disk with the finger one tooth for each day.
- It might happen that the moon does not shift and seems to be stuck. On that moment the small pin of the transmission-wheel grips into the tooth of the disk. If this does happen just turn the hands of the clock a few hours ahead until the moon disk shifts and comes free again.
- And please keep in mind that calendar days are not equal to "moon days".