Wickwire did not have a tent, sleeping bag, or water. His oxygen ran out halfway through the night, and his gas stove became inoperable. His only protection, other than his immediate winter clothing, was a thin nylon bivvy sack, which is uninsulated but windproof and helps to retain body heat. He shivered uncontrollably from the extreme cold (estimated to be -35 °F) and kept slowly sliding down the slope. He was forced to get out of his sack to remedy the problem and discovered that he was at risk of sliding over an edge that rolled off to drop below. "No one had ever survived a solo bivouac above twenty-seven thousand feet".