Despite the significant progress in unraveling Earth’s history, geologists of the late 19th century were no closer to placing absolute ages on any of the well delineated segments of geologic time than savants of a century earlier. The pages shown here from Joesph LeConte’s widely read and popular textbook Elements of Geology (1879) illustrates this contrast. The detailed or “ideal” column on the right shows the well-defined geologic timescale, with its delineated segments of Earth’s history, which are not that dissimilar to the ones used by geologists today. The column is floating in time, however; and LeConte remarks on this same page on the near impossibility of trying to imagine the lengths of time represented here. In a manner similar to Hutton, LeConte notes that the lowest portion of Earth history, the “Archean,” represents “an infinite abyss of the unrecorded” and that trying to piece together the age of the Archean “hardly belongs strictly to geology, but rather to cosmic philosophy.”
