Charley Morton received the lunch with joy.

"Ain't had time to get together grub since we came," said he, "and didn't know when I would."

"What do you want us to do?" asked Bob.

"The fire line's drawn right across from Granite Creek down there in the canon over to a bald dome. We got her done an hour ago, and pretty well back-fired. All we got to do now is to keep her from crossing anywheres; and if she does cross, to corral her before she can get away from us."

"I wish we could have got here sooner!" cried Bob, disappointed that the little adventure seemed to be flattening out.

"So?" commented Charley drily. "Well, there's plenty yet. If she gets out in one single, lonesome place, this fire line of ours won't be worth a cent. She's inside now--if we can hold her there." He gazed contemplatively aloft at a big dead pine blazing merrily to its very top. Every once in a while a chunk of bark or a piece of limb came flaring down to hit the ground with a thump. "There's the trouble," said he. "What's to keep a spark or a coal from that old coon from falling or rolling on the wrong side of the line? If it happens when none of us are around, why the fire gets a start. And maybe a coal will roll down hill from somewhere; or a breeze come up and carry sparks. One spark over here," he stamped his foot on the brushed line, "and it's all to do over again. There's six of us," added the ranger, "and a hundred of these trees near the line. By rights there ought to be a man camped down near every one of them."

"Give us our orders," repeated Bob.

"The orders are to patrol the fire line," said Morton. "If you find the fire has broken across, corral it. If it gets too strong for you, shoot your six-shooter twice. Keep a-moving, but take it easy and save yourself for to-morrow. About two o'clock, or so, I'll shoot three times. Then you can come to camp and get a little sleep. You got to be in shape for to-morrow."

"Why especially to-morrow?" asked Bob.

"Fire dies in the cool of night; it comes up in the middle of the day," explained Morton succinctly.

Bob took to the right, while Jack went in the opposite direction. His way led down hill. He crossed a ravine, surmounted a little ridge. Now he was in the worse than total darkness of the almost extinct area. Embers and coals burned all over the side hill like so many evil winking eyes. Far ahead, down the mountain, the rising smoke glowed incandescent with the light of an invisible fire beneath, Bob, blinded by this glow, had great difficulty in making his way. Once he found that he had somehow crept out on the great bald roundness of a granite dome, and had to retrace his steps. Twice he lost his footing utterly, but fortunately fell but a short distance. At last he found himself in the V of a narrow ravine.

All this time he had, with one exception, kept close track of the fire line. The exception was when he strayed out over the dome; but that was natural, for the dome had been adopted bodily as part of the system of defence. Everywhere the edge of the path proved to be black and dead. No living fire glowed within striking distance of the inflammable material on the hither side the path.

But here, in the bottom of the ravine, a single coal had lodged, and had already started into flame the dry small brush. It had fallen originally from an oak fully a hundred feet away; and in some mysterious manner had found a path to this hidden pocket. The circumstances somewhat shook Bob's faith in the apparent safety of the country he had just traversed.

However, there were the tiny flames, licking here and there, insignificant, but nevertheless dangerous. Bob carefully laid his canteens and the rake on a boulder, and set to work with his sharpened hoe. It looked to be a very easy task to dig out a path around this little fire.

In the course of the miniature fight he learned considerable of the ways of fire. The brush proved unexpectedly difficult. It would not stand up to the force of his stroke, but bent away. The tarweed, especially, was stubborn under even the most vigorous wielding of his sharpened hoe.

He made an initial mistake by starting to hoe out his path too near the blaze, forgetting that in the time necessary to complete his half-circle the flames would have spread. Discovering this, he abandoned his beginning and fell back twenty feet. This naturally considerably lengthened the line he would have to cut. When it was about half done, Bob discovered that he would have to hustle to prevent the fire breaking by him before he could complete his half-circle. It became a race. He worked desperately. The heat of the flames began to scorch his face and hands, so that it was with difficulty he could face his work. Irrelevantly enough there arose before his mind the image of Jack Pollock popping corn before the fireplace at headquarters. Continual wielding of the hoe tired a certain set of muscles to the aching point. His mouth became dry and sticky, but he could not spare time to hunt up his canteen. The thought flashed across his mind that the fire was probably breaking across elsewhere, just like this. The other men must be in the same fix. There were six of them. Suppose the fire should break across simultaneously in seven places? The little licking flames had at last, by dint of a malignant persistence, become a personal enemy. He fought them absorbedly, throwing his line farther and farther as the necessity arose, running to beat down with green brush the first feeble upstartings of the fire as it leaped here and there his barrier, keeping a vigilant eye on every part of his defences.

"Well," drawled Charley Morton's voice behind him, "what you think you're doing?"

"Corralling this fire, of course," Bob panted, dashing at a marauding little flame.

"What for?" demanded Charley.

Bob looked up in sheer amazement.

"See that rock dike just up the hill behind you?" explained Morton. "Well, our fire line already runs up to that on both sides. Fire couldn't cross it. We expected this to burn."

Bob suddenly felt a little nauseated and dizzy from the heat and violence of his exertions in this high altitude.

"Here's your canteen," Morton went on easily. "Take a swig. Better save a little. Feel better? Let me give you a pointer: don't try to stop a fire going up hill. Take it on top or just over the top. It burns slower and it ain't so apt to jump."

"I know; I forgot," said Bob, feeling a trifle foolish.

"Never mind; you've learned something," said Morton comfortably. "Let's go down below. There's fresh fire there; and it may have jumped past Elliott."

They scrambled down. Elliott and Ware were found to be working desperately in the face of the flames. The fire had not here jumped the line, but it was burning with great ferocity up to the very edge of it. If the rangers could for a half-hour prevent the heat from igniting the growths across the defence, the main fire would have consumed its fuel and died down to comparative safety. With faces averted, heads lowered, handkerchiefs over their mouths, they continually beat down the new little fires which as continually sprang into life again. Here the antagonists were face to face across the narrow line. The rangers could not give back an inch, for an inch of headway on the wrong side the path would convert a kindling little blaze to a real fire. They stood up to their work doggedly as best they might.

With entire understanding of the situation Charley motioned Bob to the front.

"We'll hold her for a minute," he shouted to the others. "Drop back and get a drink."

They fell back to seize eagerly their canteens. Bob gripped his handful of green brush and se............