History in the Layers of the Earth
The layers of the Earth had long been recognized as providing a temporal sequence of events, with broad classifications of “Primary” (igneous) and “Secondary” (sedimentary) hinting at a generic age progression. But crucially, prior to the beginning of the 19th century, this temporal sequence provided no insight into the chronology, or related history of the rocks. Instead, temporal sequences were localized and focused on specific applications, such as mining, or used to support arguments for eternal, predictive, and steady-state behavior of the Earth system. Investigations in the beginning of the 19th century, notably in the Paris Basin (see Recherches sur les ossemens fossiles de quadrupèdes), would drastically alter this perspective.
