Brief history dating

12 Oct

The second is that the rates of the physical processes in question are variable and knowledge of them was incomplete.In the late 1800's physicists, armed with a more advanced physics than that available to Descartes, made new estimates of the age of the Earth and the Sun.Notable observations included: ran from about 1780-1850.By the end of the 18'th century it was clear that the Earth had a long and varied history. The major debate was between the catastrophists, e.g., Cuvier, who held that the history of Earth was dominated by major catastrophic revolutions and the uniformitarians, e.g.

These were long on armchair speculation and short on substantive supporting evidence.The great debate was won by the uniformitarians, so much so that the degree of gradualism was overstated and the importance of catastrophes was unduly minimized.The modern period has been marked by an enormous expansion of the detailed knowledge of the geological history of the Earth and the processes that have acted during that history.If, in the year AD 1600, you had asked an educated European how old the planet Earth was and to recount its history he would have said that it was about 6000 years old and that its ancient history was given by the biblical account in Genesis.If you asked the same question of an educated European in AD 1900 you would have received a quite different answer.Descartes, however, attempted to discern a physical history of the Earth.His account was plausible by the immature standards of the Science of his times; however it quite definitely did not match the Biblical account of a completed creation in six days.In the 1700's belief in a 6000 year old Earth crumbled.Attempts to calculate the age of the Earth from physical considerations yielded estimates that ranged from 75,000 years (Buffon, 1774) to several billion years (de Maillet, Buffon).The physical models were open to question and, in retrospect, were naive. It became quite clear that many areas of the Earth had alternated between being land and being covered by seas, that there had been extensive slow sedimentation, that the mountains had not been created in situ as is but rather had a long history of slow deformation, and that long periods of erosion had shaped the Earth everywhere.By the early 1800's it was generally accepted that the Earth had a long history. The uniformatarians (Hutton 1788, Lyell 1830) pictured the Earth as being indefinitely old.