We traveled for nearly an hour when the first rumblings let it be quite clear that taking this path to save time was a mistake. The sounds were loud and ominous and echoed through the underground chamber like some distant and ancient machinery grinding to a a final halt after years of use and abuse. When we passed through a narrow corridor, we barely avoided being buried by a rain of debris falling from the ceiling and sealing the chamber. So it was that by the second hour we were trapped thoroughly. "The debris ahead is impassible," Kendrel reported to my dismay. "What?"