Reviews. 



On the Glacial Succession in Europe. By Prof. James Geikie. Tran- 

 sactions of the Royal Society of Edinburgh, Vol. XXXVII., Part 

 I. (No. 9), 1892, pp. 127-149 (with a map). 

 In this timely essay Prof. Geikie reaches the following conclusions : 



1. The record of the first glacial epoch is found in the Weyborn 

 Crag of Britain, and the ground moraine beneath the " Lower Dilu 

 vium" of the continent. During this epoch, the direction of the ice 

 movement in southern Sweden was from the south-east to the north- 

 west. This first glacial epoch of which direct evidence is adduced 

 was followed by an interglacial interval, during which the forest-bed 

 of Cromer, the breccia of Hotting, the lignites of Leffe and Pianico, 

 and certain beds in central France were deposited. During this inter- 

 glacial epoch, the climate is believed to have been very mild. 



2. There followed a second epoch of glaciation, when the ice 

 sheet of Britain became confluent with that of the continent. This 

 was the epoch during which the ice sheet reached its southernmost 

 extension. Its depositions are found in the lower boulder clays of 

 Britain, the lower diluvium of Scandinavia and north Germany (in 

 part), the lower glacial deposits of south Germany and central Russia, 

 the ground moraines and high level gravel terraces of Alpine lands, 

 and the terminal moraines of the outer zone. During this second 

 glacial epoch, Alpine glaciers are believed to have attained their 

 greatest development. This epoch of extreme glaciation was followed 

 by an interglacial interval, during which Britain is believed to have 

 been joined to the continent. During this interval, the climate became 

 temperate. In Russia (near Moscow) there seems to be evidence that 

 it was milder and more humid than that of the same region at the 

 present day. Toward the close of the mild epoch, submergence seems 

 to have been accompanied by an increasing degree of cold, which 

 finally ended in another glacial epoch. 



3. The subsidence which marked the close of the second inter- 

 glacial interval, marked likewise the inauguration of the third glacial 



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