What could have happened?
Had Tumbu in his haste missed the bear's trail?
That was not likely.

Having come so far, had he determined to go on?
That was not likely either, unless the children had urged him forward.

Knowing Mirak's bold, adventurous spirit, this seemed possible, and Roy's heart sank; but he started off running again, knowing that no matter what had happened he must follow his little master, and follow fast.
But as he ran downward and downward the frost film on the snow became less and less firm.

The sun was rising now, and even its earliest rays seemed to melt his foothold, and he began to sink at every step.

The sledge, however, appeared from the faint marks it left to have slid on without difficulty.