KKXDAI.I. : THE (iLACIKR LAKES OF CLEVELAND. 5 
At the close of the Glacial Period the recession of these 
ice-sheets took place in regular order from south to north, the 
shrinkage of the Scottish and Scandinavian sheets northwards 
and eastwards being accompanied by a recession of the Tees 
ice to the west. The river mouths were thus in turn freed from 
obstruction, and resumed their normal drainage. A noteworthy 
exception to this rule seems to have been the persistence of 
a lobe of ice overriding the northern Cleveland watershed into 
Eskdale. after the mouth of the Esk was free from ice. 
Fig. 1. 
.MAP OF THE MARJELEN SEE. 
Glacier- Lakes. 
Whenever a glacier or ice-sheet advances against or across 
the general slope of a country which is not occupied by ice, 
there w ill be a tendency to impound the natural ''drainage and 
to produce lakes. 
