1904 - 5 .] Study of the Lakes of Scotland and Denmark. 405 
lowest in August and September, the difference amounting to 2 or 
3 feet in the two seasons. Hence it follows that in our shallow 
lakes the breadth of the beach increases in summer and autumn 
to the extent of several hundred feet, and in winter and spring 
the ice or the waves cover places over wdiich one might walk dry- 
shod in summer. 
The sides of the lakes are gently sloping ; and the same remark 
applies to what the Germans term “uferbank,” and the Trench 
and Swiss term “beine.” The deeper parts of the lakes are floored 
by more or less level plains, the greatest depth being often found 
near the centre. Islands are not common, though both islands 
and banks occur. Owing to the small amount of detritus carried 
down by the rivers, deltas are usually inconspicuous, and well- 
marked banks at the embouchures of the rivers are rare. 
Erosion by waves upon the shores is seldom conspicuous, as the 
force of the waves is broken in rolling over the shallow plains, 
often covered and bound together by vegetation. The wind- 
blown sides of the lakes (especially the east-south-east shores) are 
frequently sandy, or covered with stones and pebbles, while the 
west and north-west shores are often peaty. On the other hand, 
certain parts of the lake-shores show remarkable indications of 
erosion, and these are most conspicuous where the shores are 
covered with wood ; here one may see trees with scars and rifts 
2 to 3 feet from the ground, and often showing remarkably 
irregular forms. Further, one may find many overthrown trees 
and dead shrubs standing high upon their washed-out white roots. 
In the few cases where the shores rise precipitously from the 
water’s edge marks of erosion are often found, and abundance of 
stones and pebbles washed down from the slopes above. This 
erosion, however, is to be ascribed rather to the action of ice than 
to that of waves. In spring, when the ice breaks up, it is often 
piled into heaps 2 to 4 feet high, in front of which one always 
finds a very conspicuous “ end-moraine,” consisting of gravel, 
stones, broken Phragmites, shells of mussels and Limncea, and 
various drift-materials. It may be pushed 20 to 25 feet from the 
shore, and even — to the amazement of a naturalist — remain there 
from one year to another. The ground over which the ice has 
travelled will show, after the disappearance of the ice, a very 
