Whatever the menace was it was drawing nearer with the swiftness of the wind.

He could hear it coming up the slope that sheltered the basin from the valley.
The crest of that slope was just about on a level with Thor's eyes, and as he looked the leader of the pack came up over the edge of it and stood for a moment outlined against the sky.

The others followed quickly, and for perhaps thirty seconds they stood rigid on the cap of the hill, looking down into the basin at their feet and sniffing the heavy scent with which it was filled.
During those thirty seconds Thor watched his enemies without moving, while in his deep chest there gathered slowly a low and terrible growl.

Not until the pack swept down into the cup of the mountain, giving full tongue again, did he continue his retreat.

But it was not flight.