Sixty miles farther north Kazan lay at the end of his fine steel chain, watching little Professor McGill mixing a pail of tallow and bran.  A dozen yards from him lay the big Dane, his huge jaws drooling in anticipation of the unusual feast which McGill was preparing.  He showed signs of pleasure when McGill approached him with a quart of the mixture, and he gulped it between his huge jaws.  The little man with the cold blue eyes and the gray-blond hair stroked his back without fear.  His attitude was different when he turned to Kazan.  His movements were filled with caution, and yet his eyes and his lips were smiling, and he gave the wolf-dog no evidence of his fear, if it could be called fear.

The little professor, who was up in the north country for the Smithsonian Institution, had spent a third of his life among dogs.  He loved them, and understood them.  He had written a number of magazine articles on dog intellect that had attracted wide attention among naturalists.  It was largely because he loved dogs, and understood them more than most men, that he had bought Kazan and the big Dane on the night when Sandy McTrigger and his partner had tried to get them to fight to the death in the Red Gold City saloon.  The refusal of the two splendid beasts to kill each other for the pleasure of the three hundred men who had assembled to witness the fight delighted him.  He had already planned a paper on the incident.  Sandy had told him the story of Kazan’s capture, and of his wild mate, Gray Wolf, and the professor had asked him a thousand questions.  But each day Kazan puzzled him more.  No amount of kindness on his part could bring a responsive gleam in Kazan’s eyes.  Not once did Kazan signify a willingness to become friends.  And yet he did not snarl at McGill, or snap at his hands when they came within reach.  Quite frequently Sandy McTrigger came over to the little cabin where McGill was staying, and three times Kazan leaped at the end of his chain to get at him, and his white fangs gleamed as long as Sandy was in sight.  Alone with McGill he became quiet.  Something told him that McGill had come as a friend that night when he and the big Dane stood shoulder to shoulder in the cage that had been built for a slaughter pen.  Away down in his brute heart he held McGill apart from other men.  He had no desire to harm him.  He tolerated him, but showed none of the growing affection of the huge Dane.  It was this fact that puzzled McGill.  He had never before known a dog that he could not make love him.

To-day he placed the tallow and bran before Kazan, and the smile in his face gave way to a look of perplexity.  Kazan’s lips had drawn suddenly back.  A fierce snarl rolled deep in his throat.  The hair along his spine stood up.  His muscles twitched.  Instinctively the professor turned.  Sandy McTrigger had come up quietly behind him.  His brutal face wore a grin as he looked at Kazan.

“It’s a fool job ­tryin’ to make friends with him” he said.  Then he added, with a sudden interested gleam in his eyes, “When you startin’?”

“With first frost,” replied McGill.  “It ought to come soon.  I’m going to join Sergeant Conroy and his party at Fond du Lac by the first of October.”

“And you’re going up to Fond du Lac ­alone?” queried Sandy.  “Why don’t you take a man?”

The little professor laughed softly.

“Why?” he asked.  “I’ve been through the Athabasca waterways a dozen times, and know the trail as well as I know Broadway.  Besides, I like to be alone.  And the work isn’t too hard, with the currents all flowing to the north and east.”

Sandy was looking at the Dane, with his back to McGill.  An exultant gleam shot for an instant into his eyes.

“You’re taking the dogs?”

“Yes.”

Sandy lighted his pipe, and spoke like one strangely curious.

“Must cost a heap to take these trips o’ yourn, don’t it?”

“My last cost about seven thousand dollars.  This will cost five,” said McGill.

“Gawd!” breathed Sandy.  “An’ you carry all that along with you!  Ain’t you afraid ­something might happen ?”

The little professor was looking the other way now.  The carelessness in his face and manner changed.  His blue eyes grew a shade darker.  A hard smile which Sandy did not see hovered about his lips for an instant.  Then he turned, laughing.

“I’m a very light sleeper,” he said.  “A footstep at night rouses me.  Even a man’s breathing awakes me, when I make up my mind that I must be on my guard.  And, besides” ­he drew from his pocket a blue-steeled Savage automatic ­“I know how to use this.”  He pointed to a knot in the wall of the cabin.  “Observe,” he said.  Five times he fired at twenty paces, and when Sandy went up to look at the knot he gave a gasp.  There was one jagged hole where the knot had been.

“Pretty good,” he grinned.  “Most men couldn’t do better’n that with a rifle.”

When Sandy left, McGill followed him with a suspicious gleam in his eyes, and a curious smile on his lips.  Then he turned to Kazan.

“Guess you’ve got him figgered out about right, old man,” he laughed softly.  “I don’t blame you very much for wanting to get him by the throat.  Perhaps ­”

He shoved his hands deep in his pockets, and went into the cabin.  Kazan dropped his head between his forepaws, and lay still, with wide-open eyes.  It was late afternoon, early in September, and each night brought now the first chill breaths of autumn.  Kazan watched the last glow of the sun as it faded out of the southern skies.  Darkness always followed swiftly after that, and with darkness came more fiercely his wild longing for freedom.  Night after night he had gnawed at his steel chain.  Night after night he had watched the stars, and the moon, and had listened for Gray Wolf’s call, while the big Dane lay sleeping.  To-night it was colder than usual, and the keen tang of the wind that came fresh from the west stirred him strangely.  It set his blood afire with what the Indians call the Frost Hunger.  Lethargic summer was gone and the days and nights of hunting were at hand.  He wanted to leap out into freedom and run until he was exhausted, with Gray Wolf at his side.  He knew that Gray Wolf was off there ­where the stars hung low in the clear sky, and that she was waiting.  He strained at the end of his chain, and whined.  All that night he was restless ­more restless than he had been at any time before.  Once, in the far distance, he heard a cry that he thought was the cry of Gray Wolf, and his answer roused McGill from deep sleep.  It was dawn, and the little professor dressed himself and came out of the cabin.  With satisfaction he noted the exhilarating snap in the air.  He wet his fingers and held them above his head, chuckling when he found the wind had swung into the north.  He went to Kazan, and talked to him.  Among other things he said, “This’ll put the black flies to sleep, Kazan.  A day or two more of it and we’ll start.”

Five days later McGill led first the Dane, and then Kazan, to a packed canoe.  Sandy McTrigger saw them off, and Kazan watched for a chance to leap at him.  Sandy kept his distance, and McGill watched the two with a thought that set the blood running swiftly behind the mask of his careless smile.  They had slipped a mile down-stream when he leaned over and laid a fearless hand on Kazan’s head.  Something in the touch of that hand, and in the professor’s voice, kept Kazan from a desire to snap at him.  He tolerated the friendship with expressionless eyes and a motionless body.

“I was beginning to fear I wouldn’t have much sleep, old boy,” chuckled McGill ambiguously, “but I guess I can take a nap now and then with you along!”

He made camp that night fifteen miles up the lake shore.  The big Dane he fastened to a sapling twenty yards from his small silk tent, but Kazan’s chain he made fast to the butt of a stunted birch that held down the tent-flap.  Before he went into the tent for the night McGill pulled out his automatic and examined it with care.

For three days the journey continued without a mishap along the shore of Lake Athabasca.  On the fourth night McGill pitched his tent in a clump of banskian pine a hundred yards back from the water.  All that day the wind had come steadily from behind them, and for at least a half of the day the professor had been watching Kazan closely.  From the west there had now and then come a scent that stirred him uneasily.  Since noon he had sniffed that wind.  Twice McGill had heard him growling deep in his throat, and once, when the scent had come stronger than usual, he had bared his fangs, and the bristles stood up along his spine.  For an hour after striking camp the little professor did not build a fire, but sat looking up the shore of the lake through his hunting glass.  It was dusk when he returned to where he had put up his tent and chained the dogs.  For a few moments he stood unobserved, looking at the wolf-dog.  Kazan was still uneasy.  He lay facing the west.  McGill made note of this, for the big Dane lay behind Kazan ­to the east.  Under ordinary conditions Kazan would have faced him.  He was sure now that there was something in the west wind.  A little shiver ran up his back as he thought of what it might be.

Behind a rock he built a very small fire, and prepared supper.  After this he went into the tent, and when he came out he carried a blanket under his arm.  He chuckled as he stood for a moment over Kazan.

“We’re not going to sleep in there to-night, old hoy,” he said.  “I don’t like what you’ve found in the west wind.  It may he a ­thunder-storm!” He laughed at his joke, and buried himself in a clump of stunted banskians thirty paces from the tent.  Here he rolled himself in his blanket, and went to sleep.

It was a quiet starlit night, and hours afterward Kazan dropped his nose between his forepaws and drowsed.  It was the snap of a twig that roused him.  The sound did not awaken the sluggish Dane but instantly Kazan’s head was alert, his keen nostrils sniffing the air.  What he had smelled all day was heavy about him now.  He lay still and quivering.  Slowly, from out of the banskians behind the tent, there came a figure.  It was not the little professor.  It approached cautiously, with lowered head and hunched shoulders, and the starlight revealed the murderous face of Sandy McTrigger.  Kazan crouched low.  He laid his head flat between his forepaws.  His long fangs gleamed.  But he made no sound that betrayed his concealment under a thick banskian shrub.  Step by step Sandy approached, and at last he reached the flap of the tent.  He did not carry a club or a whip in his hand now.  In the place of either of those was the glitter of steel.  At the door to the tent he paused, and peered in, his back to Kazan.

Silently, swiftly ­the wolf now in every movement, Kazan came to his feet.  He forgot the chain that held him.  Ten feet away stood the enemy he hated above all others he had ever known.  Every ounce of strength in his splendid body gathered itself for the spring.  And then he leaped.  This time the chain did not pull him back, almost neck-broken.  Age and the elements had weakened the leather collar he had worn since the days of his slavery in the traces, and it gave way with a snap.  Sandy turned, and in a second leap Kazan’s fangs sank into the flesh of his arm.  With a startled cry the man fell, and as they rolled over on the ground the big Dane’s deep voice rolled out in thunderous alarm as he tugged at his leash.  In the fall Kazan’s hold was broken.  In an instant he was on his feet, ready for another attack.  And then the change came.  He was free.  The collar was gone from his neck.  The forest, the stars, the whispering wind were all about him. Here were men, and off there was ­Gray Wolf!  His ears dropped, and he turned swiftly, and slipped like a shadow back into the glorious freedom of his world.

A hundred yards away something stopped him for an instant.  It was not the big Dane’s voice, but the sharp crack ­crack ­crack, of the little professor’s automatic.  And above that sound there rose the voice of Sandy McTrigger in a weird and terrible cry.