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.
The writers of Prentice Hall Earth Science say, on page 213: For thousands of years, most people thought that the earth was flat. But as early as 300 B.C., the ancient Greeks theorized that the earth was round. Yet they still drew maps of a flat earth. As people explored more of the world, they were able to map large areas of it. In 150 A.D., the famous Greek astronomer Ptolemy made maps that included Europe, Africa, and most of Asia.