Arthur Ganson uses humble materials to create kinetic sculptures of humor, drama, and emotion.  His work has been shown around the world, and has been an ongoing inspiration for the 10,000 Year Clock project at Long Now.  His machinated gestures play with time spans that range from the epochal to the momentary. One of the touchstone pieces for the Clock project is the Machine with Concrete.  The input of the piece is a 200 revolution per minute motor, and after series of gear reductions it's output gear is cast in concrete.  Due to the multiplicative nature of the gear train it will take upwards of two trillion years to break the final gear.  Ganson will be discussing the theme of time in his work, and will be bringing a piece to show live at the event.