"Now," said the captain, "all you have to do is to stick this nozzle down the conning tower, turn it so as to give the gas full play and pump. Of course the gas would carry without the pump, but you save time this way."
"One moment, Captain," said Jack. "How about ourselves? Won't the gas affect us as well as the Germans?"
Captain Griswold clapped a hand to his side.
"Now what do you think of that?" he demanded. "I must be getting old before my time. Here, Lands," he called one of his own men, who approached. "Go and tell Helgoson I want two dozen of those gas masks in the store room; and hustle."
The sailor hurried away. He was back within fifteen minutes, and Captain Griswold distributed the gas masks. Then he took the nozzle of the hose, poked it down the conning tower and looked around.
"Everybody ready?" he asked.
Jack also glanced around. Every man on the deck of the submarine wore a gas mask.
"All right, sir," said Jack.
"Then you turn that screw there when I give the word. All right? Then shoot!"
There was a hissing sound as Jack turned on the gas.