She went on, her breath coming pantingly now, even from her brief exertion. The snow was not so deep on the ice of the river. But a wind was rising. It came from the north and east, straight in her face, and Joan bowed her head as she pulled with Kazan. Half a mile down the river she stopped, and no longer could she repress the hopelessness that rose to her lips in a sobbing choking cry. Forty miles! She clutched her hands at her breast, and stood breathing like one who had been beaten, her back to the wind. The baby was quiet. Joan went back and peered down under the furs, and what she saw there spurred her on again almost fiercely. Twice she stumbled to her knees in the drifts during the next quarter of a mile. After that there was a stretch of wind-swept ice, and Kazan pulled the sledge alone. Joan walked at his side. There was a pain in her chest. A thousand needles seemed pricking her face, and suddenly she remembered the thermometer. She exposed it for a time on the top of the tent. When she looked at it a few minutes later it was thirty degrees below zero. Forty miles! And her father had told her that she could make it--and could not lose herself! But she did not know that even her father would have been afraid to face the north that day, with the temperature at thirty below, and a moaning wind bringing the first warning of a blizzard. The timber was far behind her now. Ahead there was nothing but the pitiless barren, and the timber beyond that was hidden by the gray gloom of the day. If there had been trees, Joan's heart would not have choked so with terror. But there was nothing--nothing but that gray ghostly gloom, with the rim of the sky touching the earth a mile away. The snow grew heavy under her feet again. Always she was watching for those treacherous, frost-coated traps in the ice her father had spoken of. But she found now that all the ice and snow looked alike to her, and that there was a growing pain back of her eyes. It was the intense cold.