Polar exploration is one of those things that you either feel or you don't -- me, I can't stand being even slightly cold -- but a good writer can make the skeptics understand just a little more of what drove nutballs like Shackleton.

I like the line about rather having a live donkey than a dead lion.

Shackleton, born in Ireland to an Anglo-Irish family, was already an Antarctic explorer of considerable repute when he and his crew set out from London on board a ship called Endurance on Aug. 1, 1914. He had been one of two people whom Robert Falcon Scott had selected to accompany him on the first assault on the South Pole in 1902; sick with scurvy, they turned back still 745 miles shy, but having traveled farther south than any other people to that point.

Six years later, this time in command of his own expedition, he set out for the Pole again; he and his companions closed to within 97 miles of their target before, recognizing that if they pushed on they could achieve their goal but almost certainly not return alive, he reluctantly decided they should abandon their effort. "I thought you'd rather have a live donkey than a dead lion," he quipped to his wife, Emily.