“The Doctor’s right!” exclaimed Rainey, bending over the trail, which still showed a bloodspot here and there.  “It’s no polar bear—­here’s the scratch of his claws where he climbed this bank.  Polar bears have no claws, only a sort of hard lump on the end of each toe.”

“No wolf, either,” said Thompson, examining the tracks carefully.  “The scratches are too long and too far apart.  But, for that matter, who would even dream of a wolf large enough to carry off a two hundred pound deer?”

The beast’s soft paws on the snow, hard-packed by Arctic winds, left a trail very difficult to follow.  But, bit by bit, they traced it out.

At last the creature, having climbed a hill, had taken down a narrow ravine where scrub willows grew thick.  And here they found unmistakable evidence that it had been some form of a great cat that had passed this way.

“Just like a cat’s track,” said Rainey.  “And look at the size of ’em; must measure five inches across!”

They paused at the edge of the willows.  They were brave men, but not fools.  Only fools would venture into that thicket, where every advantage would be on the side of the lurking monster.

“There’s a ridge up there running right along the side of this scrub,” said Rainey.  “We’ll climb up there and walk along it.  May get a glimpse of him.  Then, again, he may have come out on the other side and gone on.”

They climbed the bank and started along the ridge.  Every yellow bunch of dead willow leaves at once became for the moment a crouching tiger, but each, in turn, was passed up.  So they walked the ridge and had passed the willow clump, when Rainey gripped his companion’s arm, whispering: 

“What’s that down there to the right?  I think I saw it move.”

Thompson gazed down the narrow pass for a moment, then whispered: 

“C’mon.  It’s the very old chap.  We can skirt the next bank of rocks and be right above him.  We’re in luck.  It will be an easy shot!”

Creeping on hands and knees, with bated breath and nerves a-tingle, the boys came presently to a point above the half-hidden beast.  As they peered down at him they could barely suppress exclamations of surprise.  It was, indeed, a tiger.  And such a tiger!  Never, in any zoo or menagerie, had they seen his equal.  He was a monster, with massive head, deep chest and powerful limbs; and his thick fur—­nature’s protection against the Arctic cold—­seemed to emphasize both his size and his savageness.

“You’re the best shot,” whispered Rainey.  “Try him!”

Thompson lifted his rifle and with steady nerve aimed at a point back of the fore-leg.

The tiger, who up to this time had apparently neither heard nor scented them, but had been crouching half asleep beside his mangled prey, seemed suddenly to become aware of their presence.  Just as the rifle cracked, he sprang up the bank.  His deafening roar told that the bullet had found a mark, but it did not check his charge.