The west face is open so museum visitors can view the intricate clock mechanism in action. When the old City Hall was built in 1888, gaslight was the city's primary source of illumination. But the clock tower was too tall for gas lines to be run up to the clock, and so the faces remained dark. Around 1900, City Hall was electrified and the clock faces were illuminated. In the clock's reincarnation, its west face is open so that museum visitors may see its inner workings, and the eastern face, the face look out over the river, is illuminated so that it can be seen at night.
Clocks are precision instruments, and tower clocks have their own particular idiosyncrasies.
There is an elaborate relationship between the size of the clock face and hands, the length of the pendulum, and the weights. The entire mechanism must be perfectly tuned, each part to the other, to ensure proper operation and timekeeping. A separate weight system controls the clock bell strike. The museum has a smaller bell that was used on one of the last steam trains to operate out of Grand Rapids. The strike is toned so that its regular chiming can be heard in the galleria, but not sound throughout the building and intrude on the other exhibits and activities.