the occasional polar bear came to wrestle or gamble , folding stolen eskimo dollars out of some ancient rucksack having the appearance of a frozen , mummified corpse , one wedged for decades in a glacial wrinkle or overturned kayak , booty dating from an age preceding snow-cats and heavy duty plastics , when the sweat on a man 's brow built up in layers of silver-blue ice like a portable igloo .