"What in the world are they doing now?" said the Executive Officer.
A strange misshapen mass was rising above the bulwarks of the cutter with surprising swiftness.
"It's a balloon!" exclaimed the Captain.
"Hadn't we better open fire on her?" asked the Executive Officer.
"Not yet. I think we'd better get close enough to hail her first," answered the Captain. "She may not be anything more than a pleasure craft, you know."
The balloon was inflated by this time, and was tugging at the heavy steel hawsers by which it was attached to the cutter's hull. A cry of surprise broke from the crew of the British cruiser.
"Look! look! She's going up!"
The great balloon, inflated with the newly discovered gas, mercurite, the lightest and most powerful of all known gases, was lifting the cutter bodily into the air. Her curiously shaped hull, modelled after a shark's body, and equipped with a fin-keel for sailing on the wind, was now fully revealed. At the same instant a United States ensign was waved over her stern by a young man.
"Mr. Cortis," called the Captain, who had not thought it necessary yet to enter the conning-tower, "give him a taste of your metal."
"Ay, ay, sir," answered the Lieutenant in command of the forward 8-inch guns.