As he bent over the remains of the fire he heard a rattle of small stones, and, looking up, saw Pat coming down the declivity from the plateau where the tents had been set up. The incline was steep, and at times Pat was rolling rather than walking. He was in his shirt sleeves and bareheaded. At last his red head pitched toward the lake like a meteor in downward flight.

Frank rushed forward and caught him as he struck the beach, thus saving him from an impromptu bath. Pat struggled to his feet in an instant, rubbed his legs and arms to see if any bones had been broken, and then turned his head and looked up the incline.

“Talk about shooting the chutes!” he exclaimed. “I wonder what time I made coming down?”

“Sure you’re not hurt?” asked Frank anxiously.

“Every inch of my body has three bruises, one on top of the other,” Pat replied, “but I guess I’m able to walk. Say, but that was a roller-coaster glide!”

“Why did you try such a foolish caper?” asked Frank.

“Why, I saw you boys here,” was the reply, “and started down. You know the rest, as the yellow-covered books say. What you boys doing here, wasting your time, with the bacon burning to a crisp?”

“We came here to investigate,” was the reply, “and Jack went into the cavern, and vanished—just vapored into thin air. I’m going to build a fire in there and see if I can’t condense him!”

“Well,” Pat said, listening, “he may have vanished physically, but his voice appears to be on deck yet.”

Three sharp calls came from the cavern, and both boys dashed inside. There was no doubt now that Jack’s voice, at least, had condensed, for the shouts coming from the back of the cavern were both hearty and imperative.