The slender, dark forms came nearer and nearer every moment.

Presently the wolves had approached close enough for the occupants of the sleds to see their shining eyes looking like little balls of green fire.

A gaunt beast bolder than the others, and evidently the leader of the pack, bounded forward until he was only a few yards from the last sled.

At every jump he opened his great jaws and uttered a quick bark as if to embolden his followers.
Almost simultaneously with the red flame that burst from Wetzel's rifle came a sharp yelp of agony from the leader.

He rolled over and over.