“Yes, sir, but they stick,” replied the foreman.
An awful shower of blows now struck the door, and it went down with a splitting crash, and the detective and several policemen rushed in.
Just then the doors in the roof flew open.
Seeing the professor aboard the air ship, the officers made a rush for the Ranger to board her.
Frank grasped one of the levers and pulled it.
The gyroscopes flew around with a tremendous buzzing sound, and just as the officers reached the side of the boat she ascended into the air.
A yell of chagrin escaped the officers, for the Ranger shot through the now open roof and soared up into the dark sky.
They were baffled.
CHAPTER IV.
NOVA ZEMBLA.
“Escaped them, by thunder!” cried Frank, exultantly.