"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.