This guy was cleaning the Foucault Pendulum that's in the entrance hall of my faculty. I bravely asked him if i could take his photo, and i was so shocked by my courage that i forgot to take a good photo. So all i have is this snapshot. He told me the thing has to be polished every now and then because people will touch it, leaving handmarks on it. I am a very curious person, but i have never had the nerve to touch it, afraid i will ruin the whole thing.