Chapter 15

ANCIENT GLACIAL EPOCHS, AND MILD CLIMATES IN THE ARCTIC REGIONS

Mr. Croll's Views on Ancient Glacial Epochs--Effects of Denudation in Destroying the Evidence of Remote Glacial Epochs--Rise of Sea-level Connected with Glacial Epochs a Cause of Further Denudation--What Evidence of Early Glacial Epochs may be Expected--Evidences of Ice-action During the Tertiary Period--The Weight of the Negative Evidence--Temperate Climates in the Arctic Regions--The Miocene Arctic Flora--Mild Arctic Climates of the Cretaceous Period--Stratigraphical Evidence of Long-continued Mild Arctic Conditions--The Causes of Mild Arctic Climates--Geographical Conditions Favouring Mild Northern Climates in Tertiary Times--The Indian Ocean as a Source of Heat in Tertiary Times--Condition of North America During the Tertiary Period--Effect of High Excentricity on Warm Polar Climates--Evidences as to Climate in the Secondary and Palaeozoic Epochs--Warm Arctic Climates in Early Secondary and Palaeozoic Times--Conclusions as to the Climates of Secondary and Tertiary Periods--General View of Geological Climates as Dependent on the Physical Features of the Earth's Surface--Estimate of the Comparative Effects of Geographical and Physical Causes in Producing Changes of Climate.

_Pages_ 169-209