Forty-three years before Jules Verne, and ninety-three years before Edgar Rice Burroughs, Jacques Collin de Plancy, remembered today for his Encyclopedia of Demons and Demonology, penned Voyage to the Center of the Earth (1821), which is both an adventure story and a utopian fantasy in the Voltairean tradition. An expedition is mounted to discover the hypothetical opening at the Earth's pole, the existence of which was popularized by Tyssot de Patot's Pierre de Mesange (1720), Ludwig Holberg's Nils Klim (1741) and Casanova's Icosameron (1788). There, they discover an alien world located...