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That day they made forty miles, the trail being packed; but the next day, and for many days to follow, they broke their own trail, worked harder, and made poorer time. As a rule, Perrault travelled ahead of the team, packing the snow with webbed shoes to make it easier for them. François, guiding the sled at the gee-pole, sometimes exchanged places with him, but not often. Perrault was in a hurry, and he prided himself on his knowledge of ice, which knowledge was indispensable, for the fall ice was very thin, and where there was swift water, there was no ice at all.