FALLING BALL CLOCK: The falling ball clock is also known as the Spherical Weight Clock. This clock has no mainspring, no key and no winding required. It works purely on the gravity with the balls slowly moving down the large paddle wheel and provide necessary force to hairspring. There are total 20 steel balls all 2” in dia. When the ball completes the half rotation on paddlewheel, it simply drops down to the bottom tray( 1 ball every 4 hrs). After it collects a few of the steel balls you simply replace them back on the top track, which has a designated channel that allows the balls to roll down again on the paddle wheel. It keeps good time.