[CHAPTER XV - TO THE RESCUE]

[CHAPTER XVI - A SOUND IN THE SKY]

[CHAPTER XVII - INSIDE THE CAVE]

[CHAPTER XVIII - THE FIGHT IN THE CAVE]

[CHAPTER XIX - RESTING UP]

[CHAPTER XX - CONFERRING BY RADIO]

[CHAPTER XXI - GAINING AN ALLY]

[CHAPTER XXII - FLYING TO THE RESCUE]

[CHAPTER XXIII - THE TABLES TURNED]

[CHAPTER XXIV - FRANK SAVES THE DAY]