322 Prof. Fraukland on the Physical Cause 



sent age existing in Switzerland, Norway, and elsewhere are 

 evidently but the nearly dried-up streamlets of ancient ice-rivers 

 of enormous size. These glaciers have eroded the alpine valleys 

 of which they once held possession, have scooped out the lochs 

 and kyles of Scotland, as well as the grander fjords of Norway, 

 and have contributed in a most essential manner to the present 

 aspect of our mountain scenery. Ramsay* and Tyndall have 

 recently called attention to this action of ancient glaciers, and 

 have contended, the former that the lake-basins, the latter that 

 the valleys of the Alps have been scooped out of a comparatively 

 uniform surface. 



In no part of the world perhaps can the problem of the glacial 

 epoch be more advantageously studied than in Norway, on whose 

 ice-scarred coasts and fjords two of the essential portions of the 

 glacial apparatus — the ocean and the mountains — are constantly 

 and contemporaneously under the eye of the traveller. 2000 

 miles of coast, from Christiania to the North Cape, afford almost 

 uninterrupted evidence of the vast ice-operations which, during 

 the epoch in question, moulded nearly every feature of this re- 

 markable country. In this respect Norway has already invited 

 the researches of Esmark, Von Buch, and especially of Professor 

 James Forbes, whose laborious explorations and acute philoso- 

 phical reasoning have most materially increased our knowledge 

 of the physical phenomena of Scandinavia. To his work on 

 Norway and its glaciers I am indebted for many of the data em- 

 ployed in the following pages. It was likewise during a vacation 

 trip to Norway last summer that I received the impressions re- 

 garding the physical cause of the glacial epoch which form the 

 subject of this paper. 



Starting from Christiania coastwise, the traveller cannot fail to 

 remark the peculiar appearance of the gneiss and granite rocks 

 composing the coast and the innumerable islands which, forming 

 a natural breakwater, protect the mainland from the heavy seas 

 rolling in from the Atlantic. These rocks, here rarely rising to 

 the height of 800 or 900 feet, present nothing of that sharp and 

 rugged outline which generally characterizes such formations ; 

 on the contrary, they are smooth even to their summits, all their 

 angles worn off, and every trace of boldness and asperity effaced. 

 To the casual and uninstructed observer the action of the sea 

 suggests itself as a sufficient cause for these appearances : but it 

 does not require much scrutiny to be convinced that the ocean 

 waves have had little to do with this smoothing and polishing of 

 the coast. The want of uniformity in structure and chemical 

 composition of masses of gneiss and granite causes them to be 

 unequally acted upon by water. The latter dissolves and disin- 

 * Quart. Joura. Geol. Soc. August 1862. 



