What did Edgar Rice Burroughs name the interior of the "Hollow Earth" in his stories?
Burroughs also wrote popular science fiction and fantasy stories involving Earthly adventurers transported to various planets (notably Barsoom, Burroughs's fictional name for Mars, and Amtor, his fictional name for Venus), lost islands, and into the interior of the hollow earth in his Pellucidar stories, as well as westerns and historical romances.
Tarzan was a cultural sensation when introduced. Burroughs was determined to capitalize on Tarzan's popularity in every way possible. He planned to exploit Tarzan through several different media including a syndicated Tarzan comic strip, movies and merchandise. Experts in the field advised against this course of action, stating that the different media would just end up competing against each other. Burroughs went ahead, however, and proved the experts wrong – the public wanted Tarzan in whatever fashion he was offered. Tarzan remains one of the most successful fictional characters to this day and is a cultural icon.
Ray Bradbury said of Burroughs that "Edgar Rice Burroughs never would have looked upon himself as a social mover and shaker with social obligations. But as it turns out – and I love to say it because it upsets everyone terribly – Burroughs is probably the most influential writer in the entire history of the world." Bradbury continued that "By giving romance and adventure to a whole generation of boys, Burroughs caused them to become special."