THE ORIGIN OF LAKES. 223 



solely In hollows in drift, the barrier in this case extending- 

 all around the lake. The name " kettle-holes " has been 

 applied to lakelets of this character by some American 

 geologists, but the late Dr. Carvill Lewis, who gave a good 

 account of them, spoke of them as morainic meres. Good 

 examples occur " at Ellesmere in Cheshire. At this pic- 

 turesque locality most of the meres — over twenty-five in 

 number — -have received separate names all ending in 

 ' mere ' " (4). 



Turning now to larger lakes, which are due to barriers 

 of drift, I have given reasons for believing that the 

 principal lakes of English Lakeland are also due to the 

 blocking- of valleys by barriers of drift, and that they do not 

 occur in rock-basins. These lakes have frequently been 

 sounded, most of them in considerable detail by the late 

 Mr. Clifton Ward whose work on the Lake District was 

 one of the most substantial contributions to the geology of 

 that region (5), but especially by Dr. H. R. Mill (6) whose 

 valuable paper has given us a true insight into the char- 

 acter of the subaqueous scenery of these lakes. It is clear, 

 from perusal of Dr. Mill's work, that the subaqueous 

 features of the lakes do not differ in any essential par- 

 ticular from the subaerial features of the adjoining valleys, 

 and that subaqueous and subaerial features alike have been 

 produced by the same agents of erosion ; the character of 

 the scenery in each case forbids the supposition that it has 

 been produced by glacial erosion, and we find plenty of 

 evidence that glacial erosion has merely given a finishing 

 touch to the work of the other subaerial agents. 

 We must, therefore, attribute the formation of these 

 lakes to earth-movement or blocking of valleys by 

 drift accumulations, and I have given reasons, after study 

 of the distribution of the drift and of the anomalous 

 courses of many of the rivers of Lakeland, for attributing 

 the formation of the lakes to the latter cause. Some of 

 the lakes, such as Ullswater and Haweswater, appear to 

 drain over the drift-barrier, but the greater number, in- 

 cluding Windermere, Bassenthwaite, Thirlmere and others, 

 have the drift-filled valleys occupied by insignificant runnels. 



