The movie "Everest," now showing at the local IMAX theater, sent chills down my spine. There, in the middle of the Himalayas, a group of climbers found themselves blocked on their way to the summit by a fracture in the snow 90 feet deep. The crevasse was too wide to jump, but at the same time too narrow to simply accept as the end of their 30,000-foot attempt to conquer the highest mountain in the world. So they opened up a telescoped pole ladder, laid it across the icy ravine and in large, clunky, steel-clawed boots walked across the open spaces between its rungs, toes on one rundle, heels on the other.