Just as they expected, Pudge was breathing stertorously before seven minutes had crept by, proving his dismal foreboding to have been an empty threat. Billy was the next one to drop off; and finally Frank, too, lost track of things after he had tried various expedients in the hope of forgetting himself.
They were aroused by a sudden loud noise that sounded like an explosion. All of them sat upright as though brought in contact with a galvanic battery; but Frank desisted even when his hand was in the act of reaching for the button connected with the light.
If that had been a bursting bomb dropped by some hovering German Taube, for him to betray the exact position of the hangar by starting up the brilliant electric searchlight would be the height of folly.
“What could that have been, Frank?” Pudge was asking in trembling tones; for as it afterward turned out he had been having a weird dream, and his first thought on being so rudely aroused was that the top of a volcano he was exploring had been blown off by an eruption, sending him a mile high.
“The Germans have made a night raid, and are trying to smash the Sea Eagle, after seeing what she could do to their machines and dirigibles!” declared Billy, as if his mind had already been made up.
“Do you think so too, Frank; and are we apt to be blown up any second now by a better aimed bomb than that first one?” Pudge demanded, evidently trying hard to control himself, and show that he could face danger with an undaunted front.
Frank had had time to think. He realized that several things conflicted with such an explanation of the mysterious explosion. Voices, too, outside could be heard, and it was evident that the guards were calling to one another.
“On second thought,” Frank ventured to say, “I don’t believe that could have been a bomb. It didn’t make near enough noise, though perhaps we thought it pretty loud on being waked up so suddenly.”
“Then what could it have been, Frank?” demanded Billy.
“I’ve got an idea one of the guards may have fired at some prowler,” replied the other; “in a minute or so I’ll take the lantern and go out to see.”