8ir H. H. Hoivorth — The Scandinavian Ice-sheet. 7 



the country, but which must have been deeply covered by the 

 ice-sheet, if it ever existed ; and as I am no believer in what the 

 Americans call the plucking theory, or the tooth-drawing theory 

 as Professor Bonney calls what he so ably denounces, I consider 

 this a fatal objection to the subglacial formation of such boulders. 

 Nor can the enormous masses of rock, as large as small houses, 

 whose rounded angles clearly testify to their having been rolled, 

 be conceived as rolled by any subglacial streams on this side of 

 Saturn ! These rolled boulders seem to me to testify most 

 completely to the handiwork of the sea during a widespread 

 submergence, a submergence which, as we have seen, is postulated 

 by every inquirer into Scandinavian geology, native and foreign, 

 who has explored the country. 1 take it, in fact, that these rolled 

 boulders and pebbles were made by the same force and at the 

 same time as the rock surfaces of Scandinavia were polished and 

 mammillated. 



The Swedish geologists do not treat these rolled boulders, and the 

 beds in which they chiefly occur, as glacial, but as water-worn and 

 arranged by water, and notably is this the case in the great deposits 

 of them found in the asar, eskers, etc. 



What the Swedes treat as moraine-stuff is the accumulation in 

 certain places of masses of angular debris, mixed with sand or loam, 

 which occur in certain limited areas and which have the internal 

 structure of moraines. 



It is a curious and eloquent fact that whereas these two sets of 

 deposits generally occur separately, they also sometimes occur mixed, 

 and they occur mixed in deposits like the asar, which seem un- 

 mistakably to be of aqueous origin. Whatever the ultimate origin 

 of these accumulations of angular or subangular materials, they 

 would appear, therefore, to have existed when the submergence 

 was still in operation. If, however, they had existed throughout 

 the period of submergence, how is it they have not been sorted into 

 different materials, according to their specific gravity, and how is 

 it the stones have not been rolled into boulders and had their edges 

 rounded ? I cannot see how the Swedes get over this dilemma. 

 They clearly put their Glacial Period, to which they attribute these 

 so-called moraine heaps and mounds, before their great submergence. 

 How, then, did these materials escape being water- worn ? 



According to the view I have maintained, these angular stones and 

 blocks, which occur in such vast numbers in certain districts, like 

 Dalecarlia, are the direct result of the breaking of the strata into 

 fragments, when the district of Central Sweden was violently up- 

 heaved, and the waters which then covered a large part of it and 

 of Finland were scattered and driven in all directions. In such 

 a case there would be no rounding or rubbing of the angular debris. 

 The same waters which piled up the rounded boulders into mounds 

 and heaps would pile these up also, and in cases where the two 

 were in proximity to one another they were inevitably mixed. 



Let us now turn to another point, namely, the traction and move- 

 ment of the very large blocks. This is a subject of great difficulty 



