Experiments in Patience

Called "the world's most durable battery," the Clarendon Dry Pile powers a bell that has been ringing nonstop since 1840. An atmospheric clock at the University of Otago in New Zealand has been going strong, without winding, since 1864. These are just two of seven of the world's longest-running experiments: http://news.nationalgeographic.com/news/2013/07/130719-tar-pitch-longest-running-experiments-science/#close-modal