He heard it even as he leaped through the door in answer to the scream for aid.  His muscles gathered with that mysterious power that had always sustained him in his moments of crisis.  He took the steps in one leap, Morris immediately behind him.

“Fenris is loose,” he heard the man say.  “He’ll kill some one——!”

Ben could still hear the savage cries of the animal, seemingly from just behind the adjoining house.  A girl’s terrified voice still called for help.  And deeply appalled by the sounds, Ben wished that the rifle, such a weapon as had been his trust since early boyhood, was ready and loaded in his hands.

He raced about the house; and at once the scene, in every vivid detail, was revealed to him.  Pressed back against the wall of a little woodshed that stood behind her house a girl stood at bay,—­a dark-eyed girl whose beautiful face was drawn and stark-white with horror.  She was screaming for aid, her fascinated gaze held by a gray-black, houndlike creature that crouched, snarling, twenty yards distant.

Evidently the creature was stealing toward her in stealthy advance more like a stalking cat than a frenzied hound.  Nor was this creature a hound, in spite of the similarity of outline.  Such fearful, lurid surface-lights as all of them saw in its fierce eyes are not characteristic of the soft, brown orbs of the dog, ancient friend to man, but are ever the mark of the wild beast of the forest.  The fangs were bared, gleaming in foam, the hair stood erect on the powerful shoulders; and instantly Ben recognized its breed.  It was a magnificent specimen of that huge, gaunt runner of the forests, the Northern wolf.  Evidently from the black shades of his fur he was partly of the Siberian breed of wolves that beforetime have migrated down on the North American side of Bering Sea.

A chain was attached to the animal’s collar, and this in turn to a stake that had been freshly pulled from the ground.  This beast was Fenris,—­the woods creature that old Hiram Melville had raised from cubdom.

There could be no doubt as to the reality of the girl’s peril.  The animal was insane with the hunting madness, and he was plainly stalking her, just as his fierce mother might have stalked a fawn, across the young grass.  Already he was almost near enough to leap, and the girl’s young, strong body could be no defense against the hundred and fifty pounds of wire sinew and lightning muscle that constituted the wolf.  The bared fangs need flash but once for such game as this.  And yet, after the first, startled glance, Ben Darby felt himself complete master of the situation.

No man could tell him why.  No fact of his life would have been harder to explain, no impulse in all his days had had a more inscrutable origin.  The realization seemed to spring from some cool, sequestered knowledge hidden deep in his spirit.  He knew, in one breathless instant, that he was the master—­and that the girl was safe.