All at once Hamp sprang in excitement to his feet. He pointed toward the lower side of the ravine.

"Look!" he cried. "Oh! it's gone now. I saw a face peeping from behind the trees."

"What did the fellow look like?" demanded Jerry.

"I don't know," was the reply. "He was only there for a couple of seconds. He had savage, black eyes, and no mustache or beard. The fire shone right on him."

"Well, we've got to investigate this thing," declared Jerry. "Come on, fellows."

They delayed enough to get their guns and to light a lantern. Then they boldly climbed the bank of the ravine, and poked about among the trees.

But not a trace of the intruder could be found. There were no footprints on the few bare patches of snow.

"Are you sure you weren't mistaken?" asked Jerry.

"Not a bit of it," replied Hamp, indignantly. "I saw the face as plainly as I see yours now."

The boys listened in silence for a moment, and then they made another short search. In all directions were dense thickets of undergrowth.

Through this a man on snowshoes might easily have fled without leaving a trail.

"We may as well go back," said Jerry. "We can't find the spy, whoever he was."

For the next half-hour nothing else was talked about. Hamp was positive that he had seen the face, and his companions believed him. All were uneasy and scared. They knew that had the stranger been an honest man he would have shown himself. His spying actions and hasty flight seemed to indicate some evil design.

"We'll have to be on the watch, that's all," said Hamp. "The fellow was probably looking for a chance to steal something."

"I don't believe he'll come back," replied Brick. "He knows by this time that we're not to be trifled with."

About nine o'clock Jerry slipped away on the pretext of getting a drink.

He took an ax with him, but instead of pausing to chop the ice he went on to the headland.

Here he quickly climbed a tall pine tree. From its top he could look down the lake and over the surrounding forest. But all was dark and silent. Nowhere was the gleam of a campfire visible.

He concluded that the strangers had pushed on into the wilderness, and were no longer in the vicinity. With a relieved mind he descended from the tree and started back. He was now really thirsty, so he stopped to get a drink.

There were pretty deep shadows around him, for the timbered sides of the ravine kept the glow of the campfire shut in from the ice. He found a spot that had been chopped open at supper time, and was since frozen over to the thickness of several inches. He stooped down, ax in hand.

Just as he dealt the first stroke a low, mewling cry caused him to look up. Out on the lake, and less than twenty feet distant, crouched a long, grayish beast. With stealthy steps it came nearer and nearer, whipping its thin tail over the snow.

Jerry uttered one terrific screech that echoed far and wide through the forest. He flung the ax madly toward the creature, and, without pausing to look behind, dashed for camp at his top speed. The beast was actually in pursuit, but it stopped at a distance of thirty feet, and uttered a yowl of disappointment.

Brick and Hamp had armed themselves, having heard Jerry's first yell of terror. Hamp lifted his rifle, and fired at random. He missed, of course, but the flash and the report scared the savage creature away.

It was a full minute before Jerry could talk intelligibly.

"It would have scared the bravest man alive to be jumped on so suddenly," he declared. "I was kneeling on the ice, and the brute nearly had me. Cracky! I thought I was a goner."

"What was it?" asked Hamp. "A catamount?"

"Yes; the biggest one I ever saw. You can bet he's hungry, and savage, too."

"Do you think it's the same animal that was after us night before last?"

asked Brick.

"I reckon so," Jerry admitted, reluctantly. "It must have come across the ice. There's just one thing about it, fellows. If we expect to have any peace we've got to kill the creature."

"That's easier said than done," replied Hamp. "I wish I had taken careful aim when I had the chance. Now the measly varmint will lurk around here all night, and keep us from sleeping."

"We'll do our best to put him to sleep with a bullet," declared Jerry.

"Keep a stiff upper lip, Brick. We've got long odds on our side."

"I'm not afraid," Brick protested, stoutly. "I can kill a catamount as easy as a deer if I get the chance."

It was the chance that was wanting, however. Evidently, the beast had no intention of being killed. He was hungry enough to hang onto the forlorn chance of a I meal, but not once did he show himself, though the boys I lay behind the fire for an hour, watching with c.o.c.ked and I loaded rifles.

"The cunning fellow is lurking close by, you may be sure," said Jerry. "If we watch long enough we'll catch him in the act of s.n.a.t.c.hing the deer."

"It's no fun to sit here in the cold," replied Hamp, as he tossed a log on the fire. "How snug it looks inside the cabin. Confound that catamount!"

"You fellows turn in if you want to," suggested Jerry. "I'll keep guard for a couple of hours."

"No; I'll stick it out with you," replied Hamp.

"And so will I," added Brick.

Half an hour slipped away in silence. The drowsiness of the boys increased. They felt strongly tempted to go to bed, and leave the catamount in possession of the camp.

Suddenly they were startled to hear the dull report of a gun far back in the woods. Another shot followed, and then another.

"Something wrong," exclaimed Hamp. "Those men must be camping within a mile or two of us."

"That's where the racket comes from," admitted Jerry. "I can't account for it, though."

His lips framed the word murder, but he did not utter it.

"I hear something else," declared Brick; "a sort of a roaring noise. It sounds like the wind among the trees."

All listened intently.

"There's no wind," said Jerry, in a puzzled tone, "unless there's a hurricane coming from the west. I know now what it means. It's the howling of wolves, fellows."

No one spoke. The a.s.sertion was too plain for denial. Nearer and louder rose the weird, moaning sounds. Howl answered howl. The ravenous scavengers of the forest were out on a night hunt for food.

"Yes, it is wolves," muttered Hamp. "We ought never to have crossed the lake. The bitter weather has driven the pack down from Canada. Those brutes we saw yesterday were part of it."

"Now they're headed this way," declared Jerry. "They must have attacked the camp of those two men, and been driven off. That's what the shooting meant."

"Can't we climb trees?" Brick asked.