Orissa realized quite perfectly that Sealskin Island was much farther away from the mainland than it appeared, so on leaving the shore she pursued a direction straight west for several miles, intending to make a turn and proceed south to the island which was the terminus of her flight. That prolonged the trip somewhat, but she figured it would prove more interesting to the spectators, since for a part of the journey she would be flying parallel with the coast. On the return she planned to run straight back from the island.

When she decided they had reached a point about as far out as was the island, she attempted to make the turn—a mere segment of a circle—but in spite of Steve's warning Orissa was surprised at the stiffness of the steering gear. The engines were working beautifully and developing excellent speed, but the girl found she must apply all her strength to the wheel to make the turn.

She succeeded, and brought the head to bear directly upon the island, but the gear grated and stuck so persistently that Orissa's effort sent the entire craft careening at a steep angle. Sybil gave a gasp and clung to the supporting rods and both girls heard a loud "chug" that indicated something was wrong; but the Kane balancing device was so perfect that almost immediately the machine righted itself and regained its equilibrium, darting swiftly and in a straight line in the direction of the island.

"What was it?" asked Sybil, putting her head close to Orissa's to be heard above the whir of the motors behind them.

"The steering gear binds; that's all," was the quiet response. "I think it will work better when we are in the water."

"But what made that noise? Didn't something give way?" persisted Sybil.

"Glance behind us, dear, and see."

Sybil carefully turned so as to examine the parts of the aËroplane.

"Oh!" she exclaimed.

"Well?" said Orissa.

"That chest that Steve loaded us with. It has broken away from its fastenings and is jammed edge downward against your gear."

Orissa thought about it.

"That's unfortunate," said she. "I suppose the bolts broke when we tipped so badly. But it hasn't interfered with our engines any."

"No," answered Sybil, still examining the conditions; "but it has interfered seriously with your control, I fear. Both your levers are thrown out of position and even the front elevator bars are badly bent."

For the first time a worried expression appeared on Orissa's face.

"If that is true," she said, "our best plan is to return at once."

"Do," urged Sybil, her dark eyes very serious.

Orissa tried to turn the wheel. It resisted. She applied more strength. Something snapped and the released wheel whirled so freely that the girl nearly lost her seat. Recovering instantly she turned a pale face to her companion and said:

"We're wrecked, Sybil. But don't worry. With the boat under us and in this quiet sea we shall be quite safe."

"I'm not worrying—especially—Ris," was the reply; "but it occurs to me to wonder how you're going to get down to the ocean."

"Why?"

"You can't stop the engines, unless one of us crawls back over the planes."

"I can cut off the spark." She tried it, but the engines chugged as merrily as before. "Guess there must be a short circuit," gasped Orissa.

"And you can't depress your elevator, I'm sure."

"I'll try it," announced Orissa, grimly.

But the fatal chest balked her attempt. The elevator was steadfastly wedged into its present position; the engines were entirely beyond control and the two helpless girls faced one of the most curious conditions ever known in the history of aviation.

At an altitude of perhaps a hundred and fifty feet from the water the aËroplane sped swiftly on its way, headed a trifle to the west of south. It passed Sealskin Island even while the girls were discussing their dilemma, and stubbornly maintained its unfaltering course. The air conditions were perfect for flying; scarcely a breath of wind was felt; the sky above was blue as azure.

Suddenly Sybil laughed.

"What now?" demanded Orissa.

"I was thinking of the consternation on shore at about this moment," explained Miss Cumberford. "Won't they be amazed to see us continue this course, beyond the island? Not understanding our trouble, Daddy will think we're running away."

"So we are," replied Orissa. "I wish I knew where we are running to."

"I suppose we can't stop till the gasoline gives out," said Sybil.

Orissa shook her head.

"That's what scares me," she admitted. "Even now the Mexican shore is a mere line at the left. We're gradually diverging to a point farther out at sea, and when at last we alight, drained of the last drop of gasoline, how are we to run the boat back?"

"We can't. Steve's wonderful Hy will become a mere floating buoy on the bosom of the rolling blue," responded Sybil lightly. "Oh, I'm so glad I came, Ris! I'd no idea we were going to have such fun."

Orissa did not return her chum's smile.

"Sit still and balance her, Sybil," she said. "I'm going to make an investigation."

Exercising the necessary caution she turned and knelt upon the foot bar, clinging to the seat rail and in this position facing the Aircraft so she could examine its mechanism. Sybil had described the condition of things quite accurately. The engine control was cut off and as the gasoline tanks fed from the rear Orissa had no way of stopping the flow. The steering gear was broken and the front elevator firmly wedged in position by the chest.

"I wonder if we could manage to move this thing," she said, and getting a hand on one corner of the aluminum chest she gave a tug and tried to raise it. It proved solid and unyielding. Not heavy in itself, or perhaps in its contents, the thing was caught between the rods in such a manner that no strength of the girls, limited in movement as they were, could budge it a particle.

Realizing this, and the folly of leaving the seats to get at the gasoline feed, Orissa resumed her place and faced the inevitable as bravely as she could.

"Steve told me," she said to Sybil, "that the gasoline would last a hundred miles in air and fifty in water; that's at least two hundred miles in an air line. Have you any idea where we shall be by that time?"

"Not the slightest," responded her companion, cheerfully. "Ocean, of course; but latitude and longitude a mystery—and not important, anyhow."

Sybil Cumberford was a reserved and silent girl on most occasions. Few were attracted toward her, on this account. Her dark eyes seemed to regard the world with critical toleration and she gave one the impression of considering herself quite independent of her fellows. Moreover, Sybil was eccentric in character and prone to do and say things that invoked the grave displeasure of her associates, seeming to delight in confusing and annoying them. But there was a brighter side to this queer girl's nature, which developed only in the society of her trusted friends. On any occasion that demanded courage and resourcefulness she came to the front nobly, and at such times Sybil Cumberford became vivacious, helpful and inspiriting.

Here was such an occasion. Danger was the joy of Sybil's heart and the "breath of her nostrils." Indifferent to the ordinary details of life, any adventure that promised tribulation or disaster was fervently welcomed. Then the girl's spirits rose, her intellect fairly bristled and she developed an animation and joyous exhilaration entirely at variance with her usual demeanor.

So now, as Orissa Kane, a girl of proved courage and undaunted spirit, grew solemn and anxious at the perilous condition that confronted them, Sybil Cumberford became gay and animated.

"It's such an unusual thing, and so wholly unexpected!" she said blithely. "I'm sure, Ris, that no two girls who ever lived—in this world or any other—ever found themselves in a like dilemma. We're as helpless as babes, chummie dear; only no babes were ever forced to fly, willy-nilly, for hundreds of miles through the air to some forlorn spot in the dank, moist ocean."

Orissa let her chatter. She was trying to realize what it might mean to them and how and when, if ever, they might be rescued from their difficulties.

"Our great mistake," continued Sybil, as they swept along, "was in not rigging the machine with a wireless outfit. To be sure, neither of us could operate it; but a wireless, in such a case—if we understood its mysteries—would solve our problem."

"How?" asked Orissa.

"We could call up the shore at San Diego and tell them what's happened, and give them the direction in which we are flying; then they could send a fast steamer for us, or perhaps Madeline Dentry would loan her yacht."

"They may follow us with a steamer, anyhow," said Orissa, thoughtfully. "If we manage to land safely, Sybil—which means if we drop to the water right-side-up—we could float for some days, until we were found and rescued."

"Thirst is a terrible thing, at sea; and hunger is almost as bad."

"But in that dreadful chest, which has caused all our trouble, Steve told me he had packed provisions. Probably there is water there, too," asserted Orissa, hopefully.

"Yes, Dad said there was lunch for two. Well, that's one good feed we shall have, anyhow, provided the chest doesn't get away from us entirely, and we can manage to open it. In its present position, neither event is at all probable."

She seemed to love to discover and point out the gloomy side of their adventure, that she might exult in the dangers that menaced them.

Meantime, swift and straight as an arrow the Aircraft continued on its course. Not a skip to the engines, not an indication of any sort that the flight would be interrupted as long as a drop of gasoline remained in the tanks. They could only be patient and await the finale as bravely as possible.