OUTLINES OF LAKE SUPERIOR, 419 



square form to the direction of its mountain chains precisely as Italy 

 derives its form from the direction of its mountains ; after having 

 satisfied ourselves that the existence of an almost unbroken chain of 

 the highest mountains, over the centre of Europe and Asia, consti- 

 tutes the main difference in the physical features of the Old World, 

 when contrasted with those of America, where the principal moun- 

 tains run north and south ; after having thus ascertained the inti- 

 mate relation there is in general, between geological phenomena and 

 the geography of continents, the physical features of the different 

 parts of the world, it is a subject worthy of our attention to investi- 

 gate how far the particular features we may distinguish in a given 

 circumscribed locality may be ascribed to similar agencies, and to 

 subordinate influences depending upon the same general principles, 

 which have been active in the production of the general frame. 



Are the Swiss lakes, for instance, with their pecuHar form, as 

 naturally the consequence of geological phenomena as the general 

 features of the country ? Are the numerous fiords of Norway 

 and Maine owing to the same cause ? Is there any connection 

 which can be appreciated with any degree of precision between the 

 general course of rivers on one continent, or in various parts of the 

 same continent ? And can a single lake, for instance Lake Superior, 

 be analyzed, so as to refer the bearings of its outlines to precise 

 geological phenomena ? 



The knowledge I had before visiting Lake Superior, of the direct 

 connection of many of these apparently subordinate features in the 

 physical aspect of a country, with the main geological phenomena 

 upon which it rests, led me, during my excursions on this continent, 

 to keep this subject constantly in view. I had seen how the Lakes of 

 Neuchatel and Bienne were excavated at the junction of the Jura, 

 and the tertiary deposit at its base ; I had noticed that the Alpine 

 lakes followed fissures at right angles with the axis of elevation of 

 the Alps. I was aware that some of these lakes consist of two 

 distinct parts, probably formed at different periods, but now united by 

 the sheet of water filling them. 



With such intimations, the great Canadian lakes, which form so 

 naturally a boundary between the Northern United States and the 

 British possessions upon this continent, could not but strongly call 



