This is the Time Machine Clock: a marble machine clock that shows the time by transferring balls from the bottom onto the top track. These were made in various colors, including blue, orange, UV yellow, and black. When enough balls on the hour or minute tracks, they tilt, allowing the balls to move through and reach the bottom.
The above video shows these kinetic ball clock in action. The yellow one is UV reactive, so you can use it with a black light at night.