This shelf gathers the classic texts of alternative Earth cosmology: Samuel Rowbotham's flat-earth Zetetic Astronomy; Cyrus Reed Teed's concave, inside-out Cellular Cosmogony; William Reed's and Marshall Gardner's rival hollow-earth theories of the poles; the Great Pyramid speculations of Joseph Seiss, C. Staniland Wake, and W. Marsham Adams; Charles Gould's cryptozoological survey of dragon and sea-serpent legend; Edna Kenton's illustrated survey of the world's cosmologies; and Cosmas Indicopleustes's sixth-century Christian flat-earth treatise, in J.W. McCrindle's translation. James Hutton's foundational papers on deep time and a self-renewing Earth stand here too — less a "mystery" than the working geology several of these other theories were written to attack.

None of these theories reflects the modern scientific consensus on the Earth's shape, interior, or age; several were built to reject that consensus outright, on religious grounds or as personal cosmological systems. They are preserved as primary sources in the history of ideas about the Earth, not as competing science.