THUS THE STATE BORDER RULE:

Even so, Mawson felt troubled by a series of peculiar incidents which--he would write later--might have suggested to a superstitious man that something was badly amiss. First he had a strange dream one night, a vision of his father. Mawson had left his parents in good health, but the dream occurred, he would later realize, shortly after his father had unexpectedly sickened and died. Then the explorers found one husky, which had been pregnant, devouring her own puppies. This was normal for dogs in such extreme conditions, but it unsettled the men--doubly so when, far inland and out of nowhere, a petrel smashed into the side of Ninnis's sledge. "Where could it have come from?" Mertz scribbled in his notebook.

Now a series of near-disasters made the men begin to feel that their luck must be running out. Three times Ninnis almost plunged into concealed cracks in the ice. Mawson was suffering from a split lip that sent shafts of pain shooting across the left side of his face. Ninnis had a bout of snow-blindness and developed an abcess at the tip of one finger. When the pain became too much for him to bear, Mawson lanced it with a pocket knife--without benefit of anesthetic.

On the evening of December 13, 1912, the three explorers pitched camp in the middle of yet another glacier. Mawson abandoned one of their three sledges and redistributed the load on the two others. Then the men slept fitfully, disturbed by distant booms and cracking deep below them. Mawson and Ninnis did not know what to make of the noises, but they frightened Mertz, whose long experience of snowfields taught him that warmer air had made the ground ahead of them unstable. "The snow masses must have been collapsing their arches," he wrote. "The sound was like the distant thunder of cannon."

Next day dawned sunny and warm by Antarctic standards, just 11 degrees below freezing. The party continued to make good time, and at noon Mawson halted briefly to shoot the sun in order to determine their position. He was standing on the runners of his moving sledge, completing his calculations, when he became aware that Mertz, who was skiing ahead of the sledges, had stopped singing his Swiss student songs and had raised one ski pole in the air to signal that he had encountered a crevasse. Mawson called back to warn to Ninnis before returning to his calculations. It was only several minutes later that he noticed that Mertz had halted again and was looking back in alarm. Twisting around, Mawson realized that Ninnis and his sledge and dogs had vanished.

Mawson and Mertz hurried back a quarter-mile to where they had crossed the crevasse, praying that their companion had been lost to view behind a rise in the ground. Instead they discovered a yawning chasm in the snow 11 feet across. Crawling forward on his stomach and peering into the void, Mawson dimly made out a narrow ledge far below him. He saw two dogs lying on it: one dead, the other moaning and writhing. Below the ledge, the walls of the crevasse plunged down into darkness.

Frantically, Mawson called Ninnis's name, again and again. Nothing came back but the echo.

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