6 
kj:ndall : the glacier lakes of Cleveland. 
The Alps furnish few examples of such lakes, as they are 
best developed where the relief of the country is low and the 
ice-streams are large. The Marjelen See (Fig. 1), in the Bernese 
Oberland, is the best- known Alpine example. 
Norway, with its more extensive ice-fields, furnishes numerous 
and varied examples, but it is to the gigantic glaciers of Arctic 
America and the ice-sheet, of Greenland that we must look for 
our best illustrations of this class of phenomena. These great 
ice-floods must, in the nature of things, more frequently oppose 
and impound the drainage of the ice-free country than could 
be the case with greatly-crevassed glaciers flowing for a few 
miles down steep mountain valleys. 
An interesting chain of lakes is held up in the Chaix Hills 
by the ice-stress of the Malaspina Glacier, and the great ice- 
sheet of Grinnel Land sustains marginal lakes of large size ; 
but it is around the lobes of the Greenland Ice-cap that they 
are to be found in the greatest number and perfection. 
It is only natural, therefore, to expect that proofs would 
be forthcoming that glacier lakes of Pleistocene age had prevailed 
over areas extensive in proportion to the great magnitude of 
the ice-sheets. The first of such lakes to be identified was the 
gigantic Lake Agassiz in North America, the waters of which 
covered an area of more than one hundred thousand square 
miles,* and lesser lakes have since been described in various 
parts of North America. Similar glacier lakes have been recog- 
nised in the valley of the Black Cart, south of Glasgow, in the 
valley of the Tweed, in Glen Roy, and in the Vale of Pickering. 
The evidences by which ancient glacier lakes can be recog- 
nised are mainly four : — (1) Beaches ; (2) Deltas ; (3) Floor 
Deposits ; and (4) Overflow Channels. 
(1) Beaches. — The occurrence of beach lines, whether con- 
sisting of detrital accumulations or of mere shore-scarps, is 
clear proof of the former presence of standing water ; but no 
absolute proof, apart from included organisms, can be adduced 
to show whether it was sea or fresh water. There is a general 
* III the paper in the Q.J.(t.S. I stated that the area of Lake Agassiz was 
500,000 square miles. This was a mistake ; the figure there given was the 
area of ice-free country draining into the lake. 
