each time the heat seemed about to overwhelm her , she would reach about with her fingers to find a piece of cold snow and feel it move up through her veins to her shoulders , and thence to her throat and her chest and her head , and she chanted on with the elder women until finally it was over and they all smiled at her as they filed out of the sweat to sit around the fire , catching the smoke and fanning it about their bodies in the continuing ritual of purification .