Pellucidar
by Edgar Rice Burroughs
read by Ralph Snelson
Part 1 of the Hollow Earth series
Pellucidaris a fictional "Hollow Earth" milieu invented by Edgar Rice Burroughs for a series of action adventure stories. The stories initially involve the adventures of mining heir David Innes and his inventor friend Abner Perry after they use an "iron mole" to burrow 500 miles into the earth's crust. This is the second book in the series