"Do you think he set the big fire, Pete?"

"I don't know what to think, I'm goin' to catch him first!" was the grim reply. "I'll do my thinkin' afterward."

The glow of the big fire was dying away now. One reason for this was that the blaze was working its way behind a range of hills. Another was found in the coming of the dawn, the fire paling before the glow of the rising sun.

Dave gave a look back at the blaze in the gra.s.s he had seen started by the crouching figure. The flames were spreading in the dry, tinder-like gra.s.s, and for a moment Dave was worried. Then he reflected that the cowboys who were with the herd ought to be able to handle it, and, as Pete had said, the plowed strip would act in the same manner as had the burned area.

"We've got to take a chance," murmured Dave, "and it can't be a much worse chance than the one we took earlier in the night. And we must get that fellow!"

It would be the worst possible procedure to leave loose in the country so desperate a character as one who would deliberately start a prairie fire.

He could do untold damage.

"I wonder who he is?" mused Dave. Yet in his heart he had an answer ready.

"Some of the Molick crowd," he whispered. "Their ranch would be safe with the wind blowing the way it does now, and they must know it would send the fire right down on us. It was the Molick crowd, I'll wager a hat!"

He hurried on with the others. Dawn was breaking rapidly now. It seemed scarcely more than a few minutes since Dave saw that glow in the midnight sky, yet it was several hours. But so crowded had they been with work and worry that it seemed hardly more than one--or, at most, a few minutes.

The figure ahead was riding desperately to escape.

"He's got a good horse critter," observed Pete, admiringly. He could admire even an enemy's mount.

"Yes, but he can't keep up that speed," said Mr. Bellmore. "And our animals are fresh."

This was true, as during the fire-fighting the ponies of the Bar U ranch had been able to rest. Now they were fresh for the chase that was on. And a fierce chase it was.

Setting a prairie fire, when the person who did it could not but know it would eat its way toward a bunch of cattle, was a crime not far from horse stealing, than which there is no blacker offense in the West, where a man's life depends on his horse. And the person who was riding thus desperately away must have known, or at least feared, that quick vengeance would be dealt out to him.

"Th' skunk!" muttered Pete, as he and the others swept on. "Th' mean, onery skunk!"

Up came the sun from below the horizon, shining red in the smoke-filled air--red and dim, like some great balloon. The morning was hot with the heat of the fire, and it would soon be warmer and more depressing from the heat of the sun's rays.

"It's a good thing dad has his cattle where there's some water for them,"

said Dave.

"Yes," agreed Pete. "There isn't much, but it's better than being over at the other place, where Molick and his crowd can cut us off altogether."

"If worst comes to worst, and he's built up that dam again," said the engineer, "we'll go and tear it down once more."

"That's what we will," Pete said. "I'm not going to lose the cattle for want of some water, when we saved 'em from the fire."

Dave was about to make a remark, when he gave a cry of surprise instead.

"What's up?" asked Pete.

"Look! If that isn't Len Molick I'll eat my rope!" cried the young cowpuncher. "Len Molick started that fire!"

"It's him all right," agreed Pete, after an instant's glance.

The figure racing on ahead so desperately had turned for a moment in the saddle, and this turning gave a view of his face. Dave had seen it was his enemy--the enemy who had taunted him with his lack of knowledge concerning his birth and parentage.

"And we've caught him with the goods," remarked Pete, indulging in the slang which meant so much. "He'll go to jail for this."

"If we catch him," suggested Mr. Bellmore.

"Oh, we'll get him," declared Pete. "Come on here you cayuse you!" he called merrily to his mount.

But alas for Pete's hopes. Whether the extra burst of speed was more than his horse could respond to, or whether in the excess of his zeal Pete forgot his usual caution probably would never be known.

But the fact of the matter was that his horse Stepped into the burrow of a prairie dog, and, a moment later, the foreman went flying over the head of his steed, landing on the soft gra.s.s some distance away.

Dave and Mr. Bellmore pulled up at once, but they had hardly done so before Pete leaped to his feet.

"Ride on I Ride on!" he yelled. "Don't mind me. Get that skunk!"

"But you may be hurt!" Dave called.

"Hurt? No, not a bit! I'm all right!"

"What about the horse?" asked the engineer.

The animal had picked himself up, and walked with a limp toward his master, for Pete had trained him well.

"Poor brute's got a twisted shoulder--I'll have to ride him slow after I rub him down," Pete said, mournfully enough. "I can't make any kind of speed on him. Ride on, you fellows! Don't let that skunk get away!"

It was the law and custom of the range. When a chase was on, if one failed and fell behind, the other, or others, must keep going. It was a hard law, but life on the range was not easy, nor was it one for children.

"All right!" called Dave, recognizing the necessity for prompt action.

"We'll get him!"

"And watch out for him," Pete warned them. "He'll be desperate if he finds you're closing in on him."

"We'll watch out," said Mr. Bellmore.

Again he and Dave dashed on, leaving Pete to minister to his injured horse. The foreman at once proceeded to rub vigorously the strained shoulder with a bunch of gra.s.s. His steed winced it the pain, but seemed to know it was for its own good.

"I'll have to go back," Pete said, mournfully. "But I hope they catch that skunk!"

It was the meanest name he could think of to call Len Molick.

The chase was resumed. Pete's accident had cost Dave and his companion some precious moments and they had lost distance. But they felt that, eventually, they must win. For their horses were fresher than was the mount of the youth who had set the fire, and already they had appreciably lessened the distance between them.

Len's horse had shown a wonderful burst of speed at first, and he had secured a quick start.

"But it won't do him any good," said Dave. "We'll have him ridden down in ten minutes more."

"I hope so," murmured Mr. Bellmore, "Why. Can't Kurd stand it?"

"Oh, yes, but I'm afraid I can't. This is more riding than I've done since I had my accident, and my ankle is paining me."