Diagram showing the interconnectedness of fire inside the earth, featured in Mundus Subterraneus published in 1664-5 by Athanasius Kircher and Christoph Scheiner. The artwork shows volcanoes on the surface of the Earth, and underground fires and water channels causing them to erupt. Kircher's theory was that underground water channels, heated by the internal fires of the Earth, emerged in the sea (causing the tides) and in mountains (causing volcanoes). Athanasius Kircher (May 2, 1601 or 1602 -November 27 or 28, 1680) (master of a hundred arts) was a German Jesuit scholar celebrated for the versatility of his knowledge and particularly distinguished for his knowledge of the natural sciences, most notably in the fields of oriental studies, geology, and medicine. His "Mundus Subterraneus" enjoyed the greatest repute in his time; not only did it give an incentive to the more searching investigation of subterranean forces, but it contributed much to their final explanation. This image has been color enhanced.