Would you believe a pendulum clock that can keep time accurately to within one second per year? If you answered “yes”, you’ve either never tried to regulate a pendulum clock yourself, or you ...

As the pendulum swings once per second, it lets the escapement gear turn one notch forward at a time, turning the gears of the clock which drive the hands. It’s powered with a falling weight in ...

Because affixing clock hands five-stories high would be impractical ... At the base of the rotunda where the pendulum swings is a 55,000-piece floor mosaic that adds splashes of blue, purple ...

A watch differs from a clock In its having a vibrating wheel instead of a vibrating pendulum ; and ... during a few seconds, of the hand which winds up, gives motion for twenty-four or thirty ...