Vol. 52.] 



GLACIAL GEOLOGY OF ARCTIC EUROPE, ETC. 



729 



scratched. Fragments which I took from some of them are pro- 

 nounced, by Prof. Bonney, to be fine-grained reddish granite, 

 moderately coarse, rather felspathic gneissoid granite, a pale red 

 gneissoid rock, granitoid or slightly gneissoid rock, and a dull red 

 very fine-grained felspathic sandstone. 



By referring to the valuable and exhaustive appendix of Prof. 

 Bonney (p. 742), it will be seen that these erratics agree so closely 

 in character with the rocks in situ of that part of the Kola Penin- 

 sula, that there can be little or no doubt as to their local derivation. 

 The accurate determination of these rocks by so high an authority 

 is of great importance. It presents strong evidence that there is no 

 importation of foreign rocks among the vast accumulations of boulders 

 on the Kola Peninsula — that no ice-sheet bearing its cargo of 

 rocks from the north ever passed through Barents Sea, or impinged 

 against the northern coast of Europe. It seems to me that in this 

 local manufacture of erratics on the Kola Peninsula we meet with a 

 striking example of the destructive powers of an ice-sheet resting 

 on a comparatively level area. 



Considering the tendency of the erratics on this part of the Kola 

 Peninsula to accumulate in hollows and undulations of the surface, 

 it appears that we have evidence pointing to a somewhat sudden 

 recession or withdrawal of the ice-sheet. I do not accept a diluvial 



Fig. 6. — Diagrammatic section of boulders in hollows, neighbourhood 

 of Sviatoi Nos, Kola Peninsula. 



theory, such as a deluge sweeping the erratics into the undulations, 

 but it seems probable that during the melting of the ice-sheet there 

 was a tendency for the decomposing ice to drift the blocks into the 

 hollows as we now see them. On the other hand, for all we know 

 to the contrary, it may be incidental to an ice-sheet moving over a 

 comparatively level land to push the boulders into depressions of 

 the rock-surface beneath it. Only in one spot did I meet with a 

 formation that had somewhat the appearance of a moraine, but as 

 it consisted entirely of blocks, without any sand or smaller debris 

 visible, it may be merely an accumulation of blocks formed under the 

 ice-sheet. This mound stood on the edge of a ridge, which looks 

 down towards the valley of the Ukanskoc Piver : its elevation is 

 415 feet, and it runs nearly due north and south, is about h mile in 

 length, and about 40 feet in height. 



Eastward of the estuary of the Pctchora River the great 

 Bolshaia Zemclskija tundra stretches to the base of the Urals, and 

 along it we find proofs of elevation of the land in recent times. 

 The Arctic explorer, Mr. F. G. Jackson, in his book 'The Great 

 Frozen Land' (p. 128), tells us :— ' We had been steadily travelling 



