“And yet it is very simple,” explained Hedin.  “For years I have studied fur—­finished fur—­and in the study I have read everything I could find about fur, from the habits of the animals up through their trapping, and the handling of the skins in every step of their preparation.  And as for the Indians themselves, I have merely moved about among them and got acquainted, as I would do in a city of white men.”

Murchison interrupted him with a snort.  “An’ a thousand would try it, an’ one succeed!  ’Tis no explanation ye’ve given at all.  Ye cannot explain it.  ’Tis a something ye have that’s bred in the bone.  Ye’re a born man of the North—­an’ God pity ye for the job ye’ve got!  Cooped up in a store all day with the fanfare of a city dingin’ your ears from dawn till midnight, an’ beyond!  An’ what’s the good of it?  When ye might be living up here in the land that still lays as God made it.  The Company can use men like you.  You could have a post of your own in a year’s time.”

For many minutes Hedin puffed at his pipe.  “I am glad to hear that,” he said at length, “for I am not going back.”

“Not going back!” cried Murchison.  “D’ye mean it?  An’ what about that lass of John McNabb’s?”

“That lass of John McNabb’s has chosen another,” answered Hedin in a dull tone.

It was the seventh of June when Wentworth had dispatched the Indian with the reports to McNabb and to Orcutt, and thereafter he settled himself for three weeks of waiting.  The activity at the post bored and annoyed him.  He complained of the noisy yapping of the night-prowling dogs, cursed the children that ran against his legs in their play, and when necessity compelled him to cross the encampment, he passed among the tepees, obviously avoiding and despising their occupants.

Upon the fifth or sixth day, to rid himself of annoyance, Wentworth essayed a journey to the rapids, and because no one could be spared from the post, he ventured forth alone.  When not more than ten miles from the post, he turned his head, as he topped a rock-ribbed ridge for a casual survey of the broad brule he had just crossed.  The next instant he brought up rigidly erect as his eye caught a swift blur of motion far back on his trail at the opposite edge of the brule.  He looked again but could make out only an army of blackened stumps.  Entering the scrub with a vague sense of uneasiness, he circled among the stunted trees and took up a position under cover of a granite outcropping that gave him a view of his back trail.  He had hardly settled himself before a man stepped from behind a stump and struck out rapidly upon his trail.  The man was traveling light, apparently studying the ground as he walked.  Wentworth glanced about him and noted that the rocky ridge would give the man scant opportunity for trailing him to his position.  The figure was coming up the ridge now.  As it passed a twisted pine, Wentworth got a good look into his face, and the sight of it sent cold shivers up his spine that prickled uncomfortably at the roots of his hair.  For the face was that of Alex Thumb, and at close range Wentworth could see that the black eyes glittered evilly.  Icy fingers gripped the engineer’s heart.  He felt suddenly weak and cold.