Even in the secret passage where they were crouched, the noise of the storm came to them, and it seemed to be increasing in fury. The wind moaned, shrieked, and whistled around the island house and the rain came down in rattling sheets that played a tattoo on the sides and roof of the building.

“Here goes!” murmured Tom in a tense voice.

He drew back a little and when a sudden and louder burst of the storm’s fury enveloped the house, the young inventor hurled himself, back foremost, against the door.

There was a crackling and splintering of wood and Tom almost fell, so suddenly was he precipitated through the broken door. Recovering himself as best he could, Tom Swift saw that he had come out into a small passageway.

There was another door in front of him—an ordinary one fastened with bolts in plain view, and the passage was lighted by a window near the ceiling. Ned followed his chum through the broken secret door and the two stood for a moment, listening for anything which might indicate that their escape had been discovered.

But no sounds came to them save the noise of the storm, more in evidence now that they were closer to the outer air. Then Tom stepped to the locked door and, pushing back the bolts, swung it open. He had a momentary fear that it might lead into another strong room, but, to his own delighted surprise, as well as that of Ned, it gave out of doors and a moment later the two escaping captives stood in the wind and rain beneath the forest trees, free!

“That was luck!” murmured Ned.

“But we aren’t out of the woods yet,” replied Tom.

This was true in a double sense. The island in Lake Carlopa was densely wooded, and, so far as the young men knew, uninhabited save by the unscrupulous men who had kidnapped them. The sinister name of the place—Rattlesnake Island—kept away many campers who otherwise might have made the place popular. Perhaps, years before, there had been many of the deadly reptiles in the thickets, but it was doubtful if many were there now.

However, Tom and Ned did not give this a thought. Their main idea was to get as far as possible away from the house before Janner, Snogg and Torpy discovered that the prisoners had escaped.