Deep inside Chile’s San Jose Mine, the collapse hit the miners as a roar of sound, as if a skyscraper were crashing around them. A single block of granite-like stone, as tall as a forty-five-story building, had broken loose and was falling through the layers of the mine. It was later estimated to weigh seven hundred thousand tons, twice the weight of the Empire State Building. As the miners walked, the beams of their flashlights struck a smooth wall of rock. The men couldn’t see the extent of the slab, but some could sense the enormity of the disaster.