136 On the Glaciers and Climate of Iceland. 



steep precipices of the Scandinavian inlets, than on the com- 

 paratively thin beds of trap in Iceland. I may merely mention, 

 as an example of these phenomena, the undulated smoothed 

 surfaces, and those marked vs^ith curved lines intersecting one 

 another and uniting to form a network ; phenomena which 

 are not to be associated with a general prevalence of glaciers. 



When we determine on ascribing the origin of the striated 

 rocks principally to the action of drift ice, we have thence the 

 most certain evidence for the secular upheaving of the coasts 

 of Iceland, in their whole extent. Even in countries having 

 mild climates, the drift ice may exist under favourable cir- 

 cumstances, and may produce effects on the rocks. There is 

 even nothing unnatural in the supposition that they may 

 occur at the 45th degree of latitude ; and it is, therefore, pos- 

 sible that many phenomena in the low lands of Switzerland, 

 which are now supposed to be due to widely-extended glaciers, 

 may be explained in a simpler, and, on the whole, a more 

 natural manner. 



We are far from wishing to deny the agency of glaciers 

 in the changes by which the surface of the land has re- 

 ceived its present form ; but we are of opinion that their 

 influence has been much misunderstood and overrated, and 

 that the ideas which have been held in reference to it require 

 to be corrected and limited. 



The Icelandic glaciers cover certainly a very considerable 

 part of the island ; their surface amounting to about 200 

 square miles (about 4000 English square miles).* They ex- 

 ist only where extensive mountain ranges rise to the line of 

 perpetual snow, at the height of about 4000 feet. From such 

 elevations, as this, the glaciers descend into the lower re- 

 gions, even down to the vicinity of the sea ; and, like those 

 in the valleys of the Alps, they often overwhelm, with irre- 

 sistible power, patches of cultivated land. 



Throughout the northern half of Iceland, the hills are, for 

 the most part, of more moderate height ; and there are there 

 no glaciers, with the exception of a few in Isefiords-Syssel. 

 The greatest mass of ice lies in the south-east of the island, 



* One German square mile is about twenty-one English square miles. 



