Pellucidar

Pellucidar, the sequel to At the Earth's Core, was published in 1915. It continues the adventures of David Innes as he returns to the hollow interior of the Earth in search of his friend Perry and his lost love Dian the Beautiful. He takes with him many tools and weapons, intent on bringing civilization to the savage world within, which is populated with dinosaurs and neolithic creatures. He has many perilous adventures as he battles to survive. Pellucidar is the fictional internal surface of a Hollow Earth invented by American writer Edgar Rice Burroughs for a series of action adventure stories.^[1] In a crossover event, Tarzan, who was also created by Burroughs, visits Pellucidar.

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. Later protagonists include indigenous caveman Tanar and additional visitors from the surface world, notably Tarzan, Jason Gridley, and Frederich Wilhelm Eric von Mendeldorf und von Horst.^[2]

Geography

In Burroughs' concept, the Earth is a hollow shell with Pellucidar as the internal surface of its shell. Pellucidar is accessible to the surface world via a polar tunnel, allowing passage between both the inner and outer worlds[3] through which a rigid airship visits in the fourth book of the series.[4] Although the inner surface of the Earth has a smaller total area than the outer, Pellucidar actually has a greater land area, as its continents mirror the surface world's oceans and its oceans mirror the surface world's continents.

The peculiarities of Pellucidar's geography are caused by the concave curvature of its surface. There is no horizon; the further distant an object is, the higher it appears to be, until it is finally lost in a void of atmospheric haze.

Pellucidar is lit by a miniature sun suspended at the center of the hollow sphere, so it is perpetually overhead and gives a sensation of eternal noon wherever one is in Pellucidar. The sole exception is a region directly under a tiny geostationary moon of the internal sun. As a result, this region is under a perpetual eclipse and is known as the "Land of Awful Shadow". The moon has its own plant life and (presumably) animal life, and either has its own atmosphere or is simply suspended within Pellucidar's.