202 Sir H. H. Soworth — Surface Geology of N. Europe. 



If not moi-aines, what are the asar? Hisinger suggested that 

 they might be the remains of a gigantic denudation, the intervening 

 deposits having been swept away. This view, while it did not in 

 any way explain the internal structure of the asar, merely pro- 

 fessed to explain their external shape and distribution. It has 

 been completely analyzed by Tornebohm, and shown to be quite 

 untenable ; nor do I know anyone who now holds it, or who in 

 fact professes to understand how such a denudation could come 

 about. What kind of diurnal or other denuding agency would 

 permit of these ramparts of soft materials remaining as they are 

 when the rest of the beds were swept out? Whence could it 

 come ? How could it work so as to move up and down the country 

 irrespective of its contour? Where has the debris of the gigantic 

 denuding process gone to? How is it that the covering of the 

 asar, which is formed of finely levigated brickearths, is also the 

 covering of the intervening plains on either side ? But I will not 

 argue against a cause which has no defenders, nor kill again the 

 corpses which Tornebohm slew. 



Every Scandinavian geologist known to me now admits that the 

 asar are in some way the result of aqueous action. The contour 

 of their surface, the rounding and arrangement of the boulders in 

 them, with their longer axes symmetrically placed parallel to the 

 lines of the ramparts, the stratified sands and laminated clays, the 

 current bedding, the presence of shells and diatoms, are all con- 

 clusive that the asar are the result of aqueous action in some form 

 or other ; and Mr. James Geikie himself, who represents the high- 

 water level of English and Scotch glaoialism, says "all geologists 

 admit that the asar are in the main water-formed accumulations." 

 Erdmann, Tornebohm, Nathorst, and all the other Northern geologists 

 known to me, are of the same opinion. When we come, however, 

 to discuss the particular kind of aqueous agency to which the asar 

 may be assigned, and the method in which it worked, the unanimity 

 at once ceases. 



The superficial resemblance of the asar, when drawn on a sheet 

 of paper, to rivers with a main trunk and branching off into 

 smaller affluents, perhaps first suggested the idea that they had 

 something to do with rivers and river action ; a view which has 

 prevailed very considerably in textbooks, but which seems to me 

 to be absolutely untenable. 



Two theories of the fluviatile origin of the asar have been pro- 

 pounded, one treating them as the result of subaerial rivers and 

 the other as subglacial streams. I would first criticize the general 

 theory of fluviatile origin. 



In the first place, as we haVe seen, the asar do not run 

 along level surfaces nor along continuous slopes; but they 

 frequently run up and down hill. Sometimes they are found 

 at a height of 2,000 feet and sometimes only a few feet above 

 the sea-level, and they run up and down the undulating country 

 keeping the same general direction. Now whatever movements 

 are possible with ice under certain conditions, by which it may 



