Endurance: Shackleton's Incredible Voyage - Alfred Lansing
Survival
And yet they had adjusted with surprisingly little trouble to their new life, and most of them were quite sincerely happy. The adaptability of the human creature is such that they actually had to remind themselves on occasion of their desperate circumstances.
Marston had a Penny Cookbook, and it was in constant demand. Each night he would loan it out to one group of men or another, and they would pore over it, planning the imaginary meals they would have when they got home.
They found a little sheltered spot behind a rock and sat down, huddled together with their arms around one another for warmth. Almost at once Worsley and Crean fell asleep, and Shackleton, too, caught himself nodding. Suddenly he jerked his head upright. All the years of Antarctic experience told him that this was the danger sign—the fatal sleep that trails off into freezing death. He fought to stay awake for five long minutes, then he woke the others, telling them that they had slept for half an hour.