Then he swung his head side wise and looked for the cub.

Not a hair of Muskwa was to be seen.

Twice Thor turned his head.

After that, seeing that Muskwa was gone, he continued to retreat until he blocked the narrow passage that was his back door to safety.
The dogs were now barking like mad.

They were drooling at their mouths, their wiry crests stood up like brushes, and their snarling fangs were bared to their red gums.
Nearer and nearer they came to him, challenging him to stay, to rush them, to catch them if he could--and in their excitement they put ten yards of open space behind them.