And it was from this deck that the strange radiance came—a glow, as the boys could see, from beneath some thick glass bullseye.

[Quickly the four sprang to the deck of the submarine.] As they did so the Comet, relieved of their weight, rose slightly but almost immediately sank lower in the water.

[QUICKLY THE FOUR SPRANG TO THE DECK OF THE SUBMARINE.]

“Pound—make a racket!” cried Jerry. “Make them hear us and take us in. It’s our only chance!”

Ned and Bob kicked with their heels on the steel plates that formed the deck. Jerry made his way to the glass which covered the light, and rapped on that with his knife. At the same time he looked around for the hatchway by which admittance could be gained to the interior of the mysterious vessel.

Even while he was looking for it—and not seeing it—there was a noise almost at his feet. It was the sound of steel moving on steel, and an opening appeared, flush with the deck. It was a round opening, large enough to admit a man, and framed in it was the face of the same white-bearded and snowy-haired commander they had seen on the submarine when the boys had had their first view of her.

“Well, what is it? Why have you dared to board my vessel without being invited?” growled, rather than asked the man, speaking with a strong German accent. “What do you want?”

“To save our lives!” exclaimed Jerry, talking rapidly. “Our airship was struck by lightning, and disabled. We fell into the ocean, fortunately for us, landing partly on your submarine.”

“Ach! So!” exclaimed the German, in surprise.