It was the only guide to the direction of the blast, for the snow whirled about them every way at once, and sight was useless amid the blinding haze. Feeling, however, to some extent remained, and although their faces were freezing into dangerous insensibility, so long as they kept their course one side was still a little more painful than the other. They struggled on, urging the jaded oxen, and dragging them by their heads where the drifts were deep. The snow seemed to thicken as they went. They could not see each other a yard or two apart, and the power that kept them on their feet was dying out of them. Both had been working hard since sunrise, and weary flesh and blood cannot long endure a furious wind when the thermometer falls to forty or fifty below. Nothing broke the surface of the plain except the blowing waves of snow that swirled across their course and beat into their faces. It seemed impossible that they could keep on. Hope had almost left them when Devine suddenly called out:
"It's surely rising ground!"
Harding imagined by the oxen's slower pace, and his own labored breathing, that his comrade was right, but the rise was gradual and extensive. They might wander across it without coming near the lake; but they could take no precautions and much must be left to chance.
"Get on!" he said curtly.
By the force of the wind which presently met them he thought they had reached the summit. Somewhere near them a watercourse started and ran down to the lake; but the men could not tell which way to turn, although they knew that the decision would be momentous. One way led to shelter, the other to death in the snowy wilds.
"Left and down!" Harding cried at a venture.
They trudged on, Devine a few paces in front picking out the trail, and Harding urging forward the snow-blinded oxen. They had not gone more than a few yards when Devine suddenly disappeared. There was a rush of loosened snow apparently falling into a hollow, and then his voice rose, hoarse but exultant.
"We've struck the coulée!"
He scrambled out and it was comparatively easy to follow the ravine downhill; and soon after they left it the surface grew unusually level, and no tufts of withered grass broke the snow.
"Looks like the lake," said Devine. "We'll be safe once we hit the other side."