I remember I worked in a school built in the 50s, and it had a mechanical system that kept all the classroom clocks in sync. It was a private school, newly opened, but the owner had leased the building. I tried, along with the music/computers teacher, to figure out how to get the clocks to work, but the entire system was immensely complicated, involving a series of gears and pushrods that ran around the entire 2 story building. Our solution was to simply remove the clock faces from the walls, leaving an empty box, then covering that with a battery operated clock that each teacher could set as they pleased. I have no idea why the school had such a complicated sytem. It was fascinating but completely ridiculous.