"And I--always--until I find you or you find me." ... Presently she laughed gaily under her breath: "A solemn bargain, isn't it?"

"More solemn than marriage."

"Yes," said the girl faintly.

Something went crashing off into the woods as they reached the hogback which linked them with the group of pines whither the big game-bird had pitched into cover. Perhaps it was a roe deer; McKay flashed the direction in vain.

"If it were a Boche?" she whispered.

"No; it sounded like a four-legged beast. There are chamois and roe deer and big mountain hares along these heights."

They went on until the hog-back of sheer rock loomed straight ahead, and beyond, against a paling sky, the clump of high pines toward which they were bound.

McKay extinguished his torch and pocketed it.

"The sun will lead us back, Yellow-hair," he whispered. "Now hold very tightly to my hand, for it's a slippery and narrow way we tread together."

The rocks were gla.s.sy. But there were bushes and mosses; and presently wild gra.s.s and soil on the other side.

All around them, now, the tall pines loomed, faintly harmonious in the rising morning breeze which, in fair weather, always blows DOWN from the upper peaks into the valleys. Into the shadows they pa.s.sed together a little way; then halted. The girl rested one shoulder against a great pine, leaning there and facing him where he also rested, listening.

There reigned in the woods that intense stillness which precedes dawn--an almost painful tension resembling apprehension. Always the first faint bird-note breaks it; then silence ends like a deep sigh exhaling and death seems very far away.

Now above them the stars had grown very dim; and presently some faded out.

And after a little while a small mountain bird twittered sleepily.

Then unseen by them, the east glimmered like a sheet of tarnished silver. And out over the dark world of mountains, high above the solitude, rang the uncanny cry of an auerhahn.

Again the big, unseen bird saluted the coming day. McKay stole forward drawing his pistol and the girl followed.

The weird outcry of the auerhahn guided them, sounding from somewhere above among the black crests of the pines, nearer at hand, now, clearer, closer, more weird, until McKay halted peering upward, his pistol poised.

As yet the crests of the pines were merely soft blots above. Yet as they stood straining their eyes upward, striving to discover the location of the great bird by its clamour, vaguely the branches began to take shape against the greying sky.

Clearer, more distinct they grew until feathery ma.s.ses of pine-needles stood cl.u.s.tered against the sky like the wondrous rendering in a j.a.panese print. And all the while, at intervals, the auerhahn's ghostly shrieking made a sinister tumult in the woods.

Suddenly they saw him. Miss Erith touched McKay and pointed cautiously. There, on a partly naked tree-top, was a huge, crouching ma.s.s--an enormous bird, pumping its head at every uttered cry and spreading a big fan-like tail and beating the air with stiff-curved drooping wings.

McKay whispered: "I'll try to shoot straight because you're hungry, Yellow-hair"; and all the while his pistol-arm slanted higher and higner. For a second, it remained motionless; then a red streak split the darkness and the pistol-shot crashed in her ears.

There came another sound, too--a thunderous flapping and thrashing in the tree-top, the furious battering, falling tumult of broken branches and blindly beating wings, drumming convulsively in descent. Then came a thud; a feathery tattoo on the ground; silence in the woods.

"And so you shall not go hungry, Yellow-hair," said McKay with his nice smile.

They had done a good deal by the middle of the afternoon; they had broiled the big bird, dined luxuriously, had stored the remainder in their packs which they were preparing to carry with them into the forbidden forest of Les Errues.

There was only one way and that lay over the white shoulder of Thusis--a cul-de-sac, according to all guide-books, and terminating in a rest-hut near a cave glistening with icy stalagmites called Thusis's Hair.

Beyond this there was nothing--no path, no progress possible--only a depthless gulf unabridged and the world of mountains beyond.

There was no way; yet, the time before, McKay had pa.s.sed over the white shoulder of Thusis and had penetrated the forbidden land--had slid into it sideways, somewhere from Thusis's shoulder, on a fragment of tiny avalanche. So there was a way!

"I don't know how it happened, Yellow-hair," he was explaining as he adjusted and buckled her pack for her, "and whether I slid north or east I never exactly knew. But if there's a path into Les Errues except through the Hun wire, it must lie somewhere below Thusis.

Because, unless such a path exists, except for that guarded strip lying between the Boche wire and the Swiss, only a winged thing could reach Les Errues across these mountains."

The girl said coolly: "Could you perhaps lower me into it?"

A slight flush stained his cheek-bones: "That would be my role, not yours. But there isn't rope enough in the Alps to reach Les Errues."

He was strapping the pigeon-cage to his pack as he spoke. Now he hoisted and adjusted it, and stood looking across at the mountains for a moment. Miss Erith's gaze followed him.

Thusis wore a delicate camouflage of mist. And there were other bad signs to corroborate her virgin warning: distant mountains had turned dark blue and seemed pasted in silhouettes against the silvery blue sky. Also the winds had become prophetic, blowing out of the valleys and UP the slopes.

All that morning McKay's thermometer had been rising and his barometer had fallen steadily; haze had thickened on the mountains; and, it being the season for the Fohn to blow, McKay had expected that characteristic warm gale from the south to bring the violent rain which always is to be expected at that season.

But the Fohn did not materialise; in the walnut and chestnut forest around them not a leaf stirred; and gradually the mountains cleared, became inartistically distinct, and turned a beautiful but disturbing dark-blue colour. And Thusis wore her vestal veil in the full sun of noon.

"You know, Yellow-hair," he said, "all these signs are as plain as printed notices. There's bad weather coming. The wind was south; now it's west. I'll bet the mountain cattle are leaving the upper pastures."

He adjusted his binoculars; south of Mount Terrible on another height there were alms; and he could see the cattle descending.

He saw something else, too, in the sky and level with his levelled lenses--something like a bird steering toward him through the whitish blue sky.

Still keeping it in his field of vision he spoke quietly: "There's an airplane headed this way. Step under cover, please."

The girl moved up under the trees beside him and unslung her gla.s.ses. Presently she also picked up the oncomer.

"Boche, Kay?"

"I don't know. A monoplane. A Boche chaser, I think. Yes.... Do you see the cross? What insolence! What characteristic contempt for a weaker people! Look at his signal! Do you see? Look at those smoke-b.a.l.l.s and ribbons! See him soaring there like a condor looking for a way among these precipices."

The Hun hung low above them in mid-air, slowly wheeling over the gulf. Perhaps it was his shadow or the roar of his engines that routed out the lammergeier, for the unclean bird took the air on enormous pinions, beating his way upward till he towered yelping above the Boche, and their combined clamour came distinctly to the two watchers below.

Suddenly the Boche fired at the other winged thing; the enraged and bewildered bird sheered away in flight and the Hun followed.

"That's why he shot," said McKay. "He's got a pilot, now."

Eagle and plane swept by almost level with the forest where they stood staining with their shadows the white shoulder of Thusis.

Down into the gorge the great geier twisted; after him sped the airplane, banking steeply in full chase. Both disappeared where the flawless elbow of Thusis turns. Then, all alone, up out of the gulf soared the plane.

"The Hun has discovered a landing-place in Les Errues," said McKay.

"Watch him."

"There's another Hun somewhere along the shoulder of Thusis," said McKay. "They're exchanging signals. See how the plane circles like a patient hawk. He's waiting for something. What's he waiting for, I wonder?"

For ten minutes the airplane circled leisurely over Thusis. Then whatever the aviator was waiting for evidently happened, for he shut off his engine; came down in graceful spirals; straightened out; glided through the canyon and reappeared no more to the watchers in the forest of Thusis.

"Now," remarked McKay coolly, "we know where we ought to go. Are you ready, Yellow-hair?"