370 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [April 8, 



Fahlun on the one hand or to Danemora and Gefle on the otiier 

 (both of which routes Avere followed by M. de Verneuil and myself), 

 the osar are exhibited at intervals in still greater force, and are often 

 composed of coarse rounded materials, but in other places of hills 

 of almost pure sand. But the feature which most strikes the tra- 

 veller, particularly on the road to Danemora, is the increased size 

 of the superficial angular blocks as he approaches the source of their 

 origin. Thus at Hysby, one of the first stations, we viewed and 

 measured a block of granitic gneiss having perfectly sharp angles 

 and rent by great fissures whose length was forty feet, width twenty- 

 three, and height twenty -five feet ; and at Fellen, to the N.W. of 

 Gefle and Hannebo, we observed another 140 feet in circumference 

 and thirty feet high. 



In the tract between Danemora and the little sea-port of Kahk- 

 holm, the osar, consisting of true rolled and sandy detritus, are fre- 

 quently arranged in circular heaps of about 100 paces in diameter, 

 each capped by coarse angular blocks. Now, the vi^ater- worn materials 

 are, it will be observed, thus circularly grouped on the lowest ele- 

 vations in the midst of small plains or flats from one to two and 

 three miles wide, which are devoid of those distinct longitudinal 

 encasing ridges of granitic rocks whereby the osar have usually ob- 

 tained their prevailing long and ridge-like character. This circular 

 configuration, which very much reminded me of the "escars" in 

 certain basin-shaped valleys in Ireland, seemed perfectly to exclude 

 the possibility of such bodies being moraines, the residue of glaciers. 

 None of the loose materials, I would further observe, have scratched 

 surfaces, like those of the loose fragments in a glacial moraine. The 

 boulders are also of all sizes, from the dimensions of the fist to three 

 and four feet diameter ; and the rolled materials are here as else- 

 where perfectly distinct from the subjacent angular blocks. It is 

 moreover worthy of notice, that in the district in which these cir- 

 cular osar occur, the mounts of granite and granitic gneiss have in 

 several instances been ground down and polished on their southern 

 as well as on their northern faces, — a fact which, whilst it is totally 

 irreconcileable with the action of glaciers, is in perfect accordance 

 with the belief that such results proceeded from aqueous currents, 

 which in these bays or depressions impelled the drifted shingle and 

 sand in whirlpools and eddies, and thus lashed on all sides the pro- 

 truding hummocks of hard rock. These however are very remark- 

 able exceptions to the prevailing rule. 



In travelling northwards towards Sala, it is soon made apparent, 

 that if some of the angular blocks may have been moved short 

 distances, the rocks from which they have been derived are usually 

 to be seen not far off, and to the north. Nay, a phaenomenon soon 

 presents itself, which is, as far as I know, without parallel in any 

 other part of the earth, and which must be carefully noted in 

 our endeavours to form any rational theory respecting the causes 

 of a chief feature in the northern phsenomena. The woody ridges 

 traversed in the second station between UjDsala and Sala, i.e. from 

 Kcilfva and Brunsiitra, constitute the most southern point, at which 



