Geologic dating principles
The selections and comments here are not a complete exposition of the works of the authors mentioned; rather they were chosen to illustrate and exemplify changing perspectives over time.
In Europe the issue of the age of the Earth was not a serious one prior to the rise of science; the history of the Earth was assumed to be accounted for in Genesis.
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.
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).
Ussher accepted the Biblical account at face value, relying on the Biblical genealogies and on extant historical records.
He implicitly assumed that the world was created much as it is now.
The catastrophists (Cuvier 1812, de Beaumont 1852, Buckland 1836) accepted that the Earth was old; they disagreed with the kind of change and the rate of change that had occurred over that long history.