Tarzan at the Earth\u27s Core is the thirteenth book in the series relating the tales of Tarzan, Lord Greystoke. It was published in book form in 1930. From the dust jacket: Called from his home in the African jungle to great adventure, Tarzan summons his Waziri spearmen and joins the Jason Gridley expedition to seek the arctic opening in the earth\u27s surface that leads to the inner world of Pelucidar. Sailing by airship, they glide almost imperceptibly from the world that we know to the strange and terrifying land that lies beneath the earth\u27s crust. There, where time does not exist, where neither Tarzan\u27s jungle lore nor the charts of scientists are of any use as guides, they face the problem of rescuing an American adventurer wh...