"More than that," he again held his face to the stiffening gale, "we ourselves are in considerable danger. Whether this 'c.o.c.klesh.e.l.l,' as the skipper calls her, can weather a severe storm on the open sea, is a question. That question is to be answered within a few hours. We're in for a blow. We're too far on our way to retreat if we wished to. We must weather it. You can be of a.s.sistance to us as you suggest, and more than that, you can help us by being brave, fearless and hopeful. May we count on you?"

There was a cold, brave smile on the girl's face as she answered:

"You know my father. He has never yet been beaten. I am his child."

Then suddenly, casting all reserve aside, she gripped his arm and bestowing a warm smile upon him said almost in a whisper:

"Curlie Carson, I like you. You're real, the realest person I ever knew." Then turning swiftly about, she danced along the deck, to disappear down the hatch to the forecastle.

"Huh!" said Curlie, after a moment's thought, "I never could make out what girls are like. But one thing I'm sure of: that one will drown or starve or freeze when necessity demands it, without a murmur. You can count on her!"

Throwing a swift glance to where a thick bank of clouds was painting the night sky the color of blue-black ink, he hurried below to consult with the skipper about the weather. They were, he concluded, some three hundred and fifty miles out to sea. If this storm meant grave dangers to them, what must it mean to two boys in a seaplane skimming through the air over the sea? He shivered at the thought.

Fifteen minutes later, Curlie was in the small wireless cabin of the _Kittlewake_. With a receiver clamped over his head, with a motor purring at his feet and with the hum of wires and coils all about him, he felt more at ease and at home than he had been for many hours.

His talk with the skipper had confirmed his fears; they were in for a blow.

"A nor'-easter, sir," he had affirmed, "an' one you'll remember for many a day. Oh! we'll weather 'er, sir; somehow we'll 'ave to weather 'er.

With the millionaire heiress aboard we'll 'ave to, worse luck for it.

We'll 'ammer down the 'atches an' let 'er ride if we 'ave to but it's a jolly 'ard shaking habout we'll get, sir. But she's a 'arty, clean-hulled little boat, she is, an' she'll ride 'er some'ow."

After receiving this information, Curlie had gone directly to the wireless cabin. He was more anxious than he was willing to admit for the safety of his two charges, the millionaire's children; for Curlie did think of them as his charges. He was used to taking burdens on his own shoulders. It had always been his way.

Just now he was listening in on 600, ready to pick up any message which might come from the boys on the seaplane. That the _Stormy Petrel_ was a doomed aircraft he had not the least doubt. The only question which remained in his mind was whether the _Kittlewake_ or some other craft would reach her in time to save the two reckless boys.

Now and again as he listened he picked up a message from sh.o.r.e. The center of the storm, which was fast approaching, was to the east, off sh.o.r.e. Messages coming from the storm's direction would be greatly disturbed by static. But to the west the air was still clear.

Now he heard a ship off Long Island Sound speaking for a pilot; now some sh.o.r.e station at Boston a.s.signed to some ship a harbor s.p.a.ce; and now some powerful broadcasting station sent out to all the world a warning against the rising storm.

Tiring of all this, for a time he tuned his instrument to 200.

"Be interesting to see how far short wave lengths and high power will carry," was his mental comment.

Now he caught a faint echo of a song; now a note of laughter; and now the serious tones of some man speaking with his homefolks.

But what was this? He fancied he caught a familiar whisper. Adjusting his wires, adding all the amplifying power his instruments possessed, he listened eagerly; then, to his astonishment heard his own nickname spoken.

"h.e.l.lo, Curlie," came to him distinctly. Then, "Are you there? You remember that big bad man, the one who used heaps of power on 1200?

Well, he's gone north--very far north. You'd want to follow him, Curlie, if you knew what I know. The radiophone is going to do great things for the north, Curlie. But men like him will spoil it all. Remember this, Curlie: If you do go, be careful. Careful. He's a bad man and the stakes are big!" The whisper ceased. The silence that followed it was ghostly.

"And that," Curlie whispered softly, "came all the way from my dear old home town. She thought I was still in the secret tower room. Fine chance of my following that fellow up north. But when I get back I'll investigate. There may be something big there, just as she says there is. Yes, I'll look into it when I get back--if I do get back."

He shivered as he caught the howl of the wind in the rigging. Then, tuning his instrument back to 600, he listened once more for some message from the seaplane, the _Stormy Petrel_.

CHAPTER XV

S. O. S.

The spot of light which raced across the waters of the sea where no land was to be seen, where the black surface of the swiftly changing waters shone always beneath the occupants of the seaplane, took on an ever widening circle. There appeared to be no end to Alfred Brightwood's belief that somewhere in the midst of all this waste of waters there was an island.

Vincent Ardmore had long since given up hope of becoming rich by this mad adventure. His only hope, the one that gave strength to his arms benumbed by long clinging to the flashlight and new sight to his eyes, weary with watching, was that they might discover some bit of land, a coral island, perhaps, where they might find refuge from the sea until a craft, called to their aid, might rescue them.

The thought of returning to the mainland he had all but abandoned. The gas in the tank was too low for that; at least he was quite certain it must be.

There was a chance, of course, that if they alighted upon the water and sent out an S. O. S., the international call for aid, they would be answered by some near-by ship. But this seemed only a remote possibility. He dared not hope it would happen. They were far from any regular course of trans-Atlantic vessels and too far from sh.o.r.e to be picked up by a coast vessel or a fishing smack. The very fact that this island, marked so plainly on the ancient map, had been in this particular spot, so remote from the main sea-roads, had strengthened their belief that during all the centuries of travel it had been lost from man's memory and hidden from his view. Now this very isolation, since they were unable to locate this island, if indeed it existed at all, threatened to be their undoing.

Still they circled and circled with great, untiring sweeps. At last, releasing the searchlight, Vincent put his lips to a speaking tube.

"Let's light," he grumbled. "I'm dead. What's the use?"

"What else can we do but keep looking?" Alfred answered.

"Take a look at the gas. Maybe it will carry us back."

Even as he spoke, a strange thing happened. The air appeared suddenly to have dropped from beneath the plane. Straight down for fifty feet she dropped.

With the utmost difficulty Alfred succeeded in preventing her from taking a nose dive into the sea.

"She--she b.u.mped," he managed to pant at last. "Something the matter with the air."

And indeed there was something about the atmospheric conditions which they had not sensed. Busy as they had been they had not seen the black bank of clouds to the northeast of them. With the wild rush of air from sheer speed, they had not felt the increasing strength of the gale. Once Vincent had fancied that the sea, far beneath them, seemed disturbed, but so far beneath them was it that he could not tell.

Now in surprise and consternation, as if to steady his reeling brain, he gripped the fuselage beside him while he shrilled into the tube:

"Look! Look over there! Lightning!"

"Watch out, I'm going down," warned the other boy. "Going to light."

To do this was no easy task. Three times they swooped low, to skim along just over the crest of the waves, only to tilt upward again.

"Looks bad," grumbled the young pilot.

The fourth time, he dared it. With the spray spattering his goggles, he sent the plane right into the midst of it. For a second it seemed that nothing could save them, that the wave they had nose-dived into would throw their plane end for end and land her on her back, with her two occupants hopeless prisoners strapped head down to drown beneath her.

But at last the powerful motors conquered and, tossed by the ever increasing swells, the plane rode the sea like the stormy petrel after which she had been named.

"Quick!" exclaimed Alfred as the motors ceased to throb. "Strip off your harness and get back to the tank."

A moment later Vincent was making a perilous journey to the gas tank.

Twice the wind all but swept him into the sea; once a wave drenched him with its chilling waters. When at last he reached his destination it was only to utter a groan; more gas had been used than he had dared think.

"Can't--can't make it," he mumbled as he struggled back to his place.

"Have to send out an S. O. S. then. What wave length do you use?