With Bob's rather awkward help everything was made fast. By the time the two had packed the blankets and returned to headquarters on their way to the upper trail, they found Amy had changed her clothes, caught and saddled her own horse, tied on well-filled saddle bags, and stood awaiting them. She wore her broad hat looped back by the pine tree badge of the Service, a soft shirtwaist of gray flannel, a short divided skirt of khaki and high-laced boots. A red neckerchief matched her cheeks, which were glowing with excitement. Immediately they appeared, she swung aboard with the easy grace of one long accustomed to the saddle. Bob's lower jaw dropped in amazement.

"You going?" he gasped, unable even yet to comprehend the everyday fact that so many gently nurtured Western girls are accustomed to those rough-and-ready bivouacs.

"I wouldn't stay away for worlds!" she cried, turning her pony's head up the trail.

Beyond the upper meadow this trail suddenly began to climb. It made its way by lacets in the dry earth, by scrambles in the rocks until, through the rapidly thinning ranks of the scrubby trees, Bob could look back over all the broad shelf of the mountain whereon grew the pines. It lay spread before him as a soft green carpet of tops, miles of it, wrinkling and billowing gently as here and there the conformation of the country changed. At some distance it dropped over an edge. Beyond that, very dimly, he realized the brown shimmer rising from the plain. Far to the right was a tenuous smoke, a suggestion of thinning in the forest, a flash of blue water. This, Bob knew, must be the mill and the lake.

The trail shortly made its way over the shoulder of the ridge and emerged on the wide, gentle rounding of the crest. Here the trees were small, stunted and wind-blown. Huge curving sheets of unbroken granite lay like armour across the shoulder of the mountain. Decomposing granite shale crunched under the horses' hoofs. Here and there on it grew isolated tiny tufts of the hardy upland flowers. Above, the sky was deeply, intensely blue; bluer than Bob had ever seen a sky before. The air held in it a tang of wildness, as though it had breathed from great s.p.a.ces.

"I suppose this is the top of our ridge, isn't it?" Bob asked Jack Pollock.

The boy nodded.

Suddenly the trail dipped sharp to the left into a narrow and shallow little ravine. The bed of this was carpeted by a narrow stringer of fresh gra.s.s and flowers, through which a tiny stream felt its hesitating way. This ravine widened and narrowed, turned and doubled. Here and there groups of cedars on a dry flat offered ideal shelter for a camp.

Abruptly the stringer burst through a screen of azaleas to a round green meadow surrounded by the taller trees of the eastern slope of the mountain.

In other circ.u.mstances Bob would have liked to stop for a better sight of this little gem of a meadow. It was ankle deep with new gra.s.ses, starred with flowers, bordered with pink and white azaleas. The air, prisoned in a pocket, warmed by the sun, perfumed heavily by the flowers, lay in the cup of the trees like a tepid bath. A hundred birds sang in June-tide ecstasy.

But Jack Pollock, without pause, skirted this meadow, crossed the tiny silver creek that bubbled from it down the slope, and stolidly mounted a little knoll beyond. The trained pack horses swung along behind him, swaying gently from side to side that they might carry their packs comfortably and level. Bob turned involuntarily to glance at Amy. Their eyes met. She understood; and smiled at him brightly.

Jack led the way to the top of the knoll and stopped.

Here the edge of the mountain broke into a tiny outcropping spur that shook itself free from the pines. It const.i.tuted a natural lookout to the east. Bob drew rein so violently that even his well-trained mountain horse shook its head in protest.

Before him, hushed with that tremendous calm of vast distances, lay the Sierras he had never seen, as though embalmed in the sunlight of a thousand afternoons. A tremendous, deep canon plunged below him, blue with distance. It climbed again to his level eventually, but by that time it was ten miles away. And over against him, very remote, were pine ridges looking velvety and dark and ruffled and full of shadows, like the erect fur of a beast that has been alarmed. From them here and there projected granite domes. And beyond them bald ranges; and beyond them, splintered granite with snow in the crevices; and beyond this the dark and frowning Pinnacles; and still beyond, other mountains so distant, so ethereal, so delicately pink and rose and saffron that almost he expected they might at any moment dissolve into the vivid sky. And, strangely enough, though he realized the tremendous heights and depths of these peaks and canons, the whole effect to Bob was as something spread out broad. The sky, the wonderful over-arching, very blue sky, was the most important thing in the universe. Compared to its infinitudes these mountains lay spread like a fair and wrinkled footrug to a horizon inconceivably remote and mysterious.

Then his eye fell to the ridge opposite, across the blue canon. From one point on it a straight column of smoke rolled upward, to mushroom out and hang motionless above the top of the ridge. Its base was shot by half-seen, half-guessed flaming streaks.

Bob had vaguely expected to see a whole country-side ablaze. This single, slender column was almost absurd. It looked like a camp-fire, magnified to fit the setting, of course.

"There's the fire, all right," said Jack. "We got to get across to it somehow. Trail ends here."

"Why, that doesn't amount to much!" cried Bob.

"Don't it?" said Jack. "Well, I'd call that some shakes of a fire myself. It's covered mighty nigh three hundred acres by now."

"Three hundred acres! Better say ten."

"You're wrong," said Jack; "I've rode all that country with cattle."

"You'll find it fire enough, when you get there," put in Amy. "It's right in good timber, too."

"All right," agreed Bob; "I'll believe anything--after this." He waved his hand abroad. "Jack," he called, as that young man led the way off the edge, "can you see where Jack Main's Canon is from here?"

"Jack Main's!" repeated young Pollock. "Why, if you was on the top of the farthest mountain in sight, you couldn't see any place you could see it from."

"Good Lord!" said Bob.

The way zigzagged down the slope of the mountain. As Jack had said, there was no trail, but the tracks left by the four rangers were plainly to be discerned. Bob, following the pack horses, had leisure to observe how skilfully this way had been picked out. Always it held to the easy footing, but always it was evident that if certain turns had not been made some distance back this easy footing would have lacked. At times the tracks led far to the left at nearly the same level until one, two or three little streams had been crossed. Then without apparent reason they turned directly down the backbone of a steep ridge exactly like a half-dozen others they had pa.s.sed over. But later Bob saw that this ridge was the only one of the lot that dipped over gently to lower levels; all the rest broke off abruptly in precipitous rocks. Bob was a good woodsman, but this was his first experience in that mountaineering skill which noses its way by the "lay of the country."

In the meantime they were steadily descending. The trees hemmed them closer. Thickets of willows and alders had to be crossed. Dimly through the tree-tops they seemed to see the sky darkening by degrees as they worked their way down. At first Bob thought it the lateness of the afternoon; then he concluded it must be the smoke of the fire; finally, through a clear opening, he saw this apparent darkening of the horizon was in reality the blue of the canon wall opposite, rising as they descended. But, too, as they drew nearer, the heavy smoke of the conflagration began to spread over them. In time it usurped the heavens, and Bob had difficulty in believing that it could appear to any one anywhere as so simple a mushroom-head over a slender smoke column.

By the time the horses stepped from the slope to the bed of the canon, it was quite dark. Jack turned down stream.

"We'll cut the trail to Burro Rock pretty quick," said he.

Within five minutes of travel they did cut it; a narrow brown trough, trodden by the hoofs of many generations of cattlemen bound for the back country. Almost immediately it began to mount the slope.

Now ahead, through the gathering twilight, lights began to show, sometimes scattered, sometimes grouped, like the camp-fires of an immense army. These were the stubs, stumps, down logs and the like left still blazing after all the more readily inflammable material had been burned away. As the little cavalcade laboured upward, stopping every few minutes to breathe the horses, these flickering lights defined themselves. In particular one tall dead yellow pine standing boldly prominent, afire to the top, alternately glowed and paled as the wind breathed or died. A smell of stale burning drifted down the damp night air. Pretty soon Jack Pollock halted for a moment to call back:

"Here's their fire line!"

Bob spurred forward. Just beyond Jack's horse the country lay blackened.

The pine needles had burned down to the soil; the seedlings and younger trees had been withered away; the larger trees scorched; the fuel with which every forest is littered consumed in the fierceness of the conflagration. Here and there some stub or trunk still blazed and crackled, outposts of the army whose camp-fires seemed to dot the hills.

The line of demarcation between the burned and the unburned areas seemed extraordinarily well defined. Bob looked closer and saw that this definition was due to a peculiar path, perhaps two yards wide. It looked as though some one had gone along there with a huge broom, sweeping as one would sweep a path in deep dust. Only in this case the broom must have been a powerful implement as well as one of wide reach. The brushed marks went not only through the carpet of pine needles, but through the tarweed, the snow brush, the manzanita. This was technically the fire line. At the sight of the positiveness with which it had checked the spread of the flames, Bob's spirits rose.

"They seem to have stopped it here easy enough, already," he cried.

"Being as how this is the windward side of the fire, and on a down slope, I should think they might," remarked Jack Pollock drily.

Bob chuckled and glanced at the girl.

"I'm finding out every day how little I know," said he; "at my age, too!"

"The hard work is down wind," said Amy.

"Of course."

They entered the burned area, and climbed on up the hill. Though evidently here the ferocity of the conflagration had pa.s.sed, it had left its rear guard behind. Fallen trees still blazed; standing trees flamed like torches--but all harmlessly within the magic circle drawn by the desperate quick work of the rangers. They threaded their way cautiously among these isolated fires, watching lest some dead giant should fall across their path. The ground smoked under their feet. Against the background of a faint and distant roaring, which now made itself evident, the immediate surroundings seemed very quiet. The individual cracklings of flames were an undertone. Only once in a while a dull heavy crash smote the air as some great tree gave up the unequal struggle.

They pa.s.sed as rapidly as they could through this stricken field. The night had fallen, but the forest was still bright, the trail still plain. They followed it for an hour until it had topped the lower ridge.

Then far ahead, down through the dark trunks of trees, they saw, wavering, flickering, leaping and dying, a line of fire. In some places it was a dozen feet high; in others it sank to within a few inches of the ground--but nowhere could the eye discern an opening through it. A roar and a crackling filled the air. Sparks were shooting upward in the suction. A blast of heat rushed against Bob's cheek. All at once he realized that a forest fire was not a widespread general conflagration, like the burning of a city block. It was a line of battle, a ring of flame advancing steadily. All they had pa.s.sed had been negligible. Here was the true enemy, now charging rapidly through the dry, inflammable low growth, now creeping stealthily in the needles and among the rocks; always making way, always gathering itself for one of its wild leaps which should lay an entire new province under its ravaging. Somewhere on the other side of that ring of fire were four men. They were trying to cut a lane over which the fire could not leap.

Bob gazed at the wall of flame with some dismay.

"How we going to get through?" he asked.

"We got to find a rock outcrop somewheres up the ridge," explained Jack, "where there'll be a break in the fire."

He turned up the side of the mountain again, leading the way. After a time they came to an outcrop of the sort described, which, with some difficulty and stumbling, they succeeded in crossing.

Ahead, in the darkness, showed a tiny licking little fire, only a few inches high.

"The fire has jumped!" cried Bob.

"No, that's their backfire," Pollock corrected him.