The Extra Things added to the Book-Added details biography of Author-Added ancient information-Details of the series in which this book is published-Illustrated new images-Quotes are added to each chapter-Added Index to get a quick view and interface-Grammar correction is done-Summary of the Book is included-Meaning of the title is givenThe fifth installment of Edgar Rice Burroughs's Pellucidar series Back to the Stone Age recounts the strange adventures of Lieutenant von Horst, a member of the original crew that sailed to Pellucidar with Jason Gridley and Tarzan who is left behind in the inner world. Von Horst wanders friendless and alone from one danger to the next among the Stone Age peoples, mighty reptiles, and huge animals that have been extinct on the outer crust for thousands of years. But woven among the tales of savage cavemen in the country of the Basti, the hideous Gorbuses in the caverns beneath the Forest of Death, and the terrible Gaz is the story of the love this cultured hero feels for a barbarian slave girl who has spurned and discouraged him, working instead toward her own mysterious goal.Excerpt: The eternal noonday sun of Pellucidar looked down upon such a scene as the outer crust of earth may not have witnessed for countless ages past, such a scene as only the inner world of the earth's core may produce today.