Introduction The writer had discussed various aspects of the so-called Tertiary mountain belt of the earth, especially its mode of origin and significance in the later chapters of the earth’s history, in the following papers: Bearing of the Tertiary mountain belt on the origin of the earth’s plan: Bulletin of the Geological Society of America, volume 21, 1910, pages 179–226. The lateral migration of land masses [abstract] : Proceedings of the Washington Academy of Sciences, volume 13, number 29, 1923, pages 445–447. Movement of continental masses under the action of tidal forces: Pan-American Geologist, volume 43, February, 1925, pages 15–50. Greater Asia and isostasy: American Journal of Science, 5th series, volume 12, July, 1926, pages 47–67. Salient points in Tertiary epeirogeny [abstract] : Bulletin of the Geological Society of America, volume 38, 1926, pages 107–108. Sliding continents and tidal and rotational forces: American Association of . . .