“Oh, Ripley,” he called.  The officer turned and retraced his steps.  “You’ve heard of Lapierre’s fort to the eastward.  Have you ever been there?”

Ripley shook his head.  “No, but I’ve heard he has one somewhere around the east end of the lake.”

MacNair laughed.  “Yes, and if you hunted the east end of the lake for it you could hunt a year without finding it.  If you really want to know where it is, come along, I’ll show you.  I happen to be going there.”

“What’s the idea?” asked the officer, regarding MacNair quizzically.

“The idea is just this.  Lapierre’s no fool.  He’s got as good a chance of getting me as I have of getting him.  And if anything happens to me you fellows will lose a lot of valuable time before you can locate that fort.  I don’t know myself exactly why I’m taking you there, except that—­well, if anything should happen to me, Lapierre would—­you see, he might—­that is——­ Damn it!” he broke out wrathfully.  “Can’t you see he’ll have things his own way with her?”

Ripley grinned broadly.  “Oh!  So that’s it, eh?  Well, a fellow ought to look out for his friends.  She seemed right anxious to have you put where nothing would hurt you.”

“Shut up!” growled MacNair shortly.  “And before we start there’s one little condition you must agree to.  If we find Lapierre at the fort, in return for my showing you the place, you’ve got to promise to make no attempt to arrest him without first returning to Fort Resolution.  If I can’t get him in the meantime I ought to lose.”

“You’re on,” grinned Ripley, “I promise.  But man, if he’s there he won’t be alone!  What chance will you have single-handed against a whole gang of outlaws?”

MacNair smiled grimly.  “That’s my lookout.  Remember, your word has passed, and when we locate Lapierre, you head back for Fort Resolution.”

The other nodded regretfully, and when MacNair turned away from the fort and headed eastward along the south shore of the lake, the officer fell silently in behind the dogs.

They camped late in a thicket on the shore of South Bay, and at daylight headed straight across the vast snow-level, that stretched for sixty miles in an unbroken surface of white.  That night they camped on the ice, and toward noon of the following day drew into the scrub timber directly north of the extremity of Peththenneh Island.

Long after dark they made a fireless camp directly opposite the stronghold of the outlaws on the shore of Lac du Mort.  Circling the lake next morning, they reconnoitred the black spruce swamp, and working their way, inch by inch, passed cautiously between the dense evergreens in the direction of the high promontory upon which Lapierre had built his “Bastile du Mort.”