Wanting a video to show in the classroom when teaching WWI? In which John Green teaches you about railroads, and some of the ways they changed the world, and how they were a sort of microcosm for the Industrial Revolution as a whole. Prior to the invention of steam powered railroads, pretty much all locomotion had been muscle-powered. You either walked where you wanted to go, or rode on an animal to get where you were going. The railroad changed human perception of time and space, making long di