This is another function of the marine lighthouse. It also give the time of the tides.
A single hand is enough. It makes a complete revolution of the dial in 12 hours 25 minutes and 12 seconds which corresponds to half the theoretical lunar day, nearly 2.4 seconds; I could not do better. But that’s okay; because I found that the duration of the tides vary more or less than about 40 minutes in the year due primarily to the elliptic trajectory of the moon around the earth and to the earth around the sun. Phew! Divide 44712 seconds is possible by 23 thanks to the strange split type “ACBAR” visible in the center and also by 27.
The gears are made of boxwood. The wheels are made of birch plywood like aviation. The frame of the lighthouse is cleared elm. The dial and lamp are exotic wood Wenge (beautiful but eats tools). The scriptures, the needle and the white light are ox horn.
The movement is driven by a micro motor turning on 220V.