"No; why?"
"I'm sure I can see the ground below," returned the colonel.
Chester glanced over the side of the plane.
"By Jove! So can I," he exclaimed. He glanced at the indicator again. It still read a trifle over a thousand feet. "Something wrong some place," he said to himself.
He tilted the elevating lever, but the plane did not answer by a sudden rush upward. Chester gave a long whistle.
"What's the matter?" demanded Colonel Anderson.
"I don't know," returned Chester. "We're going down gradually, I know that, but the indicator still reads a thousand feet and I can't move the plane any higher."
"And you don't know what is wrong?"
"Haven't the slightest idea. I'm no airship expert."
"Then you shouldn't try to run one," declared Ivan.