Astounded, Jack and Captain Hardy looked up and beheld a sight the like of which they had never seen before.

“Great Neptune!” gasped the captain. “A ship sailing in the air!”

This was what it seemed.

But in place of sails were flapping wings. The hull was of different shape. It was a ship, but not one intended for sailing the seas.

That it was not a supernatural apparition was evident, for at the rail were four men, all of them shouting encouraging words.

“Keep up, friends!” came down from above. “We will help you!”

“Ahoy!” gasped Captain Hardy, in amazement. “Who are you?”

“This is Frank Reade, Jr.’s airship, the Dart. We are Americans!”

“And so are we,” replied Hardy. “I’ve commanded many a good ship in my life, but I never yet saw one that sailed in the air.”

At this the aerial voyagers laughed.