“Watch my back, Frank. Keep low behind that nearest tree and let ’em have it. They’re in that long grass.”

As he spoke Art, worming his way rapidly forward to a position behind the trunk of one of the spruces, began firing rapidly.

Frank, in the opposite direction, fired several shots into the long grass. He had an uncanny feeling, for he could see no forms at which to fire, and the preliminary volley poured into the camp was not repeated, so he had no index as to the enemy positions.

Jack, Bob and Farnum, rolled over, awakened by the shots, but Frank called fiercely: “Keep down.”

Realizing something of the situation, the three grabbed their rifles, laying by their sides, and, keeping down, prepared to fire as soon as they could see something at which to aim.

Mr. Hampton stirred in his tent a moment later. He had been sleeping hard, and had not awakened instantly as had the others. Moreover, a dull ache gripped his head, preventing him from thinking clearly and from comprehending instantly what was occurring. He lay a moment, wondering what had awakened him. All was still outside, for Frank and Art had ceased firing to await some sign from the unseen enemy. Mr. Hampton decided to peer out and investigate what had disturbed him. He crawled from his dog tent and stood up.

At his appearance, a ragged volley burst once more from the long grass surrounding the tiny grove, for his figure stood forth clearly and made an excellent target. Spinning about, Mr. Hampton fell heavily to the ground.

A wild yell of triumph went up at this indication that the leader had been hit. Jack leaped up regardless of consequences and ran to his father, dragging him into the tent, while bullets whipped around him. Bob ran to his assistance. To the hidden enemy it must have seemed as if their opponents were demoralized. At any rate, they grew more courageous, and started a rush.

From three sides, it came, the figures of the oncoming men only partially seen as they crouched low and darted through the grass. But the long stems waving above them marked their paths, and there were three still on watch who would have to be dealt with.

Frank, Art and Farnum marked where the waving grass indicated the enemy. Each guarded a side of the little grove. On the fourth side lay the stream.

“Wait’ll they’re close, fellows, then give it to ’em,” cautioned Farnum. “Ready. Let’s go.”

The three repeating rifles spoke as one, and from the long grass came howls and shrieks of pain and terror. What followed was brief but lively. Each of the three pumped his rifle as fast as possible, and the bullets poured into the grass almost as fast as if sprayed from the throat of a machine gun. The return fire was heavy but high, whipping through the branches of the spruce trees overhead.

Reinforcements added to the strength of the defenders, for Bob darted out of the tent, crouched over, and flung himself beside Frank, beginning to shoot even as he talked.

“Mr. Hampton escaped by a miracle,” he said. “Bullet creased his head and stunted him. He’ll be all right.”

The rush was broken. Whoever was in the grass, feared to advance farther in the face of that fire. The long grass ceased to wave, indicating the attackers had come to a halt. But they did not retreat. The menace was still there.

“Anybody hit?” Farnum called out.

“Not me,” said Art.

“Nor me,” answered Frank.

“Thank our lucky stars for that,” answered Farnum.

They all lay in a semi-circle, facing different directions, but close enough to each other to make communication in ordinary tones possible. Relieved to discover that all were untouched, despite the bullets that had rained on the camp, Farnum next inquired anxiously after Mr. Hampton, and Bob answered he had been only stunned.

“I reckon these fellows are Lupo and his gang,” Farnum remarked. “But he must have had more men than we expected, or he wouldn’t be attacking us like this.”

“What’ll we do?” growled Art. “Looks like they got us penned in.”

“Oh, but we stopped their rush,” protested Frank.

“Yes,” said Art, “but they ain’t beatin’ it as I can see. An’ when we want to up an’ leave camp, what’s goin’ to happen?”

Frank was about to reply, when Bob who was beside him, pointed with his rifle toward the gap between the two hills, from the top of one of which they earlier had seen the reindeer herd in the next valley.

“Look there, Frank,” he exclaimed excitedly. “What do you make of that?”

“Where? I don’t——Oh, yes; now I see. Something moving.”

“Sure is something moving,” Bob said.

Already the short twilight was beginning to lighten, as the sun after its dip to the edge of the northern horizon now swung higher.

“Bob.”

“What?”

“I believe that’s the reindeer herd.”

“From that valley over the hill? The reindeer we saw when we were up there on the hill top?”

“Yes, sir.”

“But how in the world?”

“Why, I noticed that the other valley swung around between those two little hills. The reindeer are just grazing along, hunting new pasture. And, say, Bob!”

“Well, what now?”

“I’ve got a bully idea.”

Abruptly, Frank wormed his way around to face Art on his right, who was keeping watch against surprise on his side of the little clump of trees sheltering them.

“Art,” said he, “look over there, between those two little hills. Are those reindeer? The reindeer we saw from the hilltop?”

“Reckon so,” said Art, after a critical inspection.

“Well, Art, can reindeer be stampeded? Like cattle, I mean.”

“Reckon so. Why?”

“Well, I’m going to try it,” Frank declared in a determined tone. Still prone, he began to wriggle out of his clothes, and pulling up his legs, to unlace his boots and kick them off.

“Are you crazy, Frank?” Bob demanded, puzzled, while Art and Farnum took their eyes from the coverts ahead to look at Frank in astonishment.

“Crazy? No more than usual,” Frank replied, as he completed disrobing, and now lay naked under the spreading branches of the spruce. “But I’m going to slip into the water and float down to that hill, then get in behind the reindeer and stampede them. You see what’ll happen then, don’t you?”

Bob stared at his companion, wide-eyed. Dawning comprehension crept into his eyes, and he began to smile. Then he chuckled.

“You little hound,” he said, employing a pet expression among the boys, denoting admiration.

“But, say, what’s the idea?” demanded Art sharply, from his position several yards away.

Frank had started wriggling forward, and waited until he was close to Art and Farnum before replying. Then he repeated his assertion that he intended floating downstream until behind the slow-moving herd of reindeer, when he would land and attempt to stampede them.

“You see how it is,” he said. “You yourselves admit that we’re in a tight place. Lupo’s forces have cover in that long grass, and can wait us out. Here among the trees there is no grass to hide us. The minute we get up and start to move around, we expose ourselves. Therefore, the best thing to do, is to drive them out of their cover, isn’t it?”

“Sure,” said Art. “But how you going to do it with——”

He was about to ask how Frank intended to drive their enemies from cover by stampeding the reindeer, but Frank grinned at him, and he paused. Dawning comprehension came into his eyes, too.

“That’s it,” Frank said. “I see you get my idea.”

He turned his gaze toward Farnum, farthest from the center, but who had overheard the conversation.

“You see, Mr. Farnum,” he said, “when the reindeer come dashing down, Lupo’s men will have to run for it to get out of the way. A stampeding herd isn’t anything to monkey with, I expect. Then you’ll have your chance. But the reindeer won’t dash in among these few close-set trees, so you’ll be safe. No, sir; as I figure it, they’ll just head right on past here and try to get through the hills beyond.”

Farnum’s glance approved.

“A fine idea,” he said, but then he added in a tone of doubt: “I don’t know as I ought to let you go, though. Mr. Hampton wouldn’t like it, maybe, putting yourself into danger like that.”

“Oh, nonsense,” said Frank. “I can slip unseen into the water. And I can swim like a seal. Ask Bob.”

And at once, to prevent any interruption of his plans, he resumed worming his way to the bank of the river.

The river ran at this point between six-foot banks, and the clump of trees in which camp was situated stood so close to the water that the roots of several projected through the soil of the land. Frank had little difficulty in getting down to the water, and felt sure that he accomplished the feat unseen by the enemy. He let himself into the stream, which was of sufficient depth right up to the bank to enable him to float downstream under the protection of the high bank, without the necessity of wading out to get to deeper water.

“For God’s sake, be careful, boy,” whispered Farnum, as Frank disappeared.

Frank was naked, and unarmed except for a long knife. He had not figured out how he would set about stampeding the reindeer. He was leaving that to chance. What concerned him now was to get to a position behind the herd without discovery. He stuck close inshore, floating, his eyes roving along the edge of the bluff above him for signs of the enemy.

None was to be seen. After all, he thought, it was hardly likely that any of the enemy lay in hiding here, as none of the shots fired at them had come from so close to the river. On the contrary, the enemy lay inland, showing they had come upon the camp from the landward side. Becoming bolder, therefore, he turned over and struck out, swimming strongly, the long knife in a sheath at his belt. He felt for it several times, to reassure himself it was there and had not fallen out.

Frank was a strong swimmer. Indeed, this was the one athletic sport at which he excelled both Bob and Jack, although they, too, were excellent swimmers. It did not take him long, therefore, aided by the current, to come abreast of the trees clothing the first of the two hills between which the reindeer had entered their valley. The hill sloped abruptly down to the water, and Frank had marked from camp how trees clothed it entirely, even dipping into the stream. When he had passed, as he believed, beyond a point at which there was any possibility of his being seen, he seized a branch of a willow tree and pulled himself ashore. Then, after climbing a short distance up the hill, he began working his way around it through the trees. Presently he was on the hillside facing the valley where were his friends in the distant clump of trees, and the enemy hidden in the long grass. The reindeer had not moved far. They were only a short distance from him, and Frank hurried forward at the best pace he could command.