stepped to the mouth of the cave—they went outside. There was little danger from the natives now, as their attention was fixed on something else.
A moment later Tom and Ned saw what this was.
Floating in the air, almost over the cave, was a great airship—a large craft, nearly the size of the Red Cloud. Hardly able to believe the evidence of their eyes, Tom and Ned watched it. Whence had it come? Whither was it going?
"It's a triplane!" murmured Ned.
"A triplane!" repeated Tom. "Yes—it is—and it's the airship of Andy Foger! Our rivals are on our track!"
He continued to gaze upward as the triplane shot forward, the noise of the motor being plainly heard. Then, with howls of fear, the Indians turned and fled. The rival airship had vanquished them.