Instantly the floor began to sink beneath him and in great alarm he turned and made a leap that enabled him to grasp the rocky sides of the wall and regain a footing in the passage through which he had just come.
Scarcely had he obtained this place of refuge when a mighty crash resounded throughout the cavern and the sound of a rushing torrent came from far below.

Inga felt in his pocket and found several matches, one of which he lighted and held before him.

While it flickered he saw that the entire floor of the cavern had fallen away, and knew that had he not instantly regained his footing in the passage he would have plunged into the abyss that lay beneath him.
By the light of another match he saw the opening at the other side of the cave and the thought came to him that possibly he might leap across the gulf.

Of course, this could never be accomplished without the marvelous strength lent him by the Blue Pearl, but Inga had the feeling that one powerful spring might carry him over the chasm into safety.

He could not stay where he was, that was certain, so he resolved to make the attempt.
He took a long run through the first cave and the short corridor; then, exerting all his strength, he launched himself over the black gulf of the second cave.