404 PROF. NORDENSKIOLD, EXPEDITION TO GREENLAND. 



True icebergs are formed only in those glaciers which terminate 

 in the manner indicated in Fig. 5 ; though pieces of ice of 

 considerable dimensions may fall from a steep precipice (Fig. 4). 

 These various kinds of glaciers occur not only in Greenland, but 

 also in other ice-covered polar lands, e.g. in Spitzbergen, though 

 on so much smaller a scale than in Greenland, that one never 

 meets in the surrounding waters with icebergs at all comparable 

 in magnitude with those of Davis Strait. 



In Spitzbergen, and probably also in some parts of Greenland, 

 the ice passes into the sea in the following manner. 



Fig. 6. Inland Ice abutting on a mud-bank. 



As I have already remarked in the account of the geological 

 relations of Spitzbergen,* this last-mentioned kind of termination 

 of inland ice towards the sea is met with only either in those 

 places where the limits of the inland ice rapidly recede, or where 

 the ice breaks for itself a new channel or way to the sea. This 

 is, for example, the case with Axels Glacier in Bell Sound, which, 

 when I first visited the spot in 1858, had an edge like that 

 indicated in Fig. 6, but which a couple of years latter filled the 

 whole of the harbour lying before it, and is now terminated in the 

 manner shown in Fig. 5. 



The great denuding effect of the glaciers has been, as is known, 

 proved by numerous and accurate investigations. Greenland also 

 offers examples of this in the long and deep fjords that indent its 

 coasts, and which, if they run parallel to ante-glacial depressions 

 of the earth's crust, yet, as the smoothed, scratched, and grooved 

 rocks, and the erratic blocks strewn high up upon the slopes show, 

 have been widened, formed, and cleansed from earth, gravel-beds, 

 and looser sedimentary mountain-detritus by the operation of the 

 glaciers. The mere effect of the immovable inland ice cannot be 

 anything like so great. Nevertheless, here also the earth and the 

 layers of gravel are completely washed away by the rapid glacier- 

 streams running under the ice. The subjacent original rock is 

 thus exposed, and perhaps to some extent worn away, especially 

 in places where the ice passes over layers of limestone, sandstone, 

 or slate. Its original depressions, filled during the older geological 

 periods, therefore re-appear, and often form — when the ice-covering 

 has again retired — the basins of those beautiful lakes which 

 characterize all glacial lands. To assume that the whole lake-basin 



(?) 



