Clock Moon Dial History
The phase of the moon is still popular on modern mechanical clock movements. It is interesting to know why and when this started becoming a popular feature to add to grandfather clocks.
Why it started
In the late 1600's traveling took awhile and was also hazardous at night when it was dark. The people would depend on the light of the moon to see what they are doing when they were out. The phase of the moon function was added to the floor clocks for this purpose. People could make travel plans with the moon light helping them to see.
In the 1700's clocks started to have the hump on the top of the clock dial for the moon phase. The arched dial was able to accommodate the lunar display disk. The moon was painted on the disk and the disk would rotate once a month. It was a simple and practical addition to the clock.
Some clock dials with the arch were produced with alternate animations besides the moon phase. Rocking ships and jumping deer figures among other things would rock back and forth. These animations did not have any practical functionality as the phase of the moon did. It was a simple design and was connected to the pendulum motion. If the pendulum move, the animation would rock, they were connected.
That is the history of the clock moon dial in its simplest form. Interesting how people lived and relied so heavily on there clocks back then. In the days of outhouses and traveling with horse and buggy, a clock was an important appliance.