Cryosol | Soil Monoliths Cryosols (or Gelisols in USDA Soil Taxonomy) have permafrost either within 1 m of the surface or within 2 m if the pedon is strongly cryoturbated in the active layer. Monoliths.soilweb.ca
Among the ancient Greeks, Homer thought the world to be flat. In contrast, Pythagoras postulated that the earth was round. A century later, Aristotle sided with the theory of the roundness of the earth.
One of the first western models of the Earth that wasn't flat was that of the greek thinker Anaximander (610 B.C. - 546 B.C.). He thought the Earth was a cylinder. However Ancient Greeks knew the earth was round as early as the 6th century B.C.