C PEOCEEDINGS OF THE GEOLOGICAL SOCIETY. 



working his way back by analytical reasoning, calling to his as- 

 sistance meteorological as well as geological evidence, the laws of 

 physical science, and the counteracting influence of the two op- 

 posing forces heat and cold, he comes to the conclusion that these 

 marks are the result of "glacial action ; and by further reasoning on 

 the various phenomena above alluded to, he concludes that they 

 have been caused by ice borne by an arctic current flowing from 

 north-east to south-west. The denudation of the rocks in many 

 parts of Sweden is enormous, but rivers and weathering will not 

 account for this. The author observes (vol. i. p. 103) that " on the 

 watershed not far from Tann Poss at the roadside (at a height 

 which Eobert Chambers estimates at 2000 feet) the clearest marks 

 of glacial action are still perfectly fresh on rocks, in spite of weather 

 and rivers. These marks prove that ice travelled over the hills from 

 north-east to south-west, now 2000 feet above the present sea-level, 

 at the place where streams now part and run to the Baltic and to the 

 Atlantic." 



As Scandinavia is now generally admitted to be rising from the 

 sea, there is nothing preposterous in assuming that the greater part, 

 if not the whole, of Sweden may once have been covered up by the 

 waves of an arctic sea, in which currents must have existed, flowing, 

 as now, in different directions, from north and south, according to 

 those physical laws by which the movements of the ocean-currents 

 are still regulated. 



But the question of land-glaciers flowing down from high regions, 

 and partly excavating the valleys down which they flow, and leav- 

 ing their marks also in the shape of scratchings and striae on the 

 rocky flanks of the valleys, is not overlooked by the author ; and on 

 this subject also much valuable information may be gleaned from 

 the pages in question. I will only add, that the many illustrations 

 contained in this volume, and the quaint sources from which the 

 author has sometimes drawn them, render his work one of great 

 interest, and which it is impossible to peruse without deep thoughts 

 and suggestions being forced on the reader's mind. 



Before concluding these observations, I wish to bring to your 

 notice one or two points which appear to me to merit the serious 

 attention of geologists in the present day. Prof. E-amsay, in his 

 Anniversary Address from this chair, alluded to the breaks in succes- 

 sion of the British Palseozoic and Mesozoic strata, and suggested the 

 probability that these breaks represented periods of time even longer 

 than those to which the various existing fossiliferous formations of 

 Great Britain bear witness. Dr. Bigsby also not long ago brought 

 under our notice a very interesting paper on missing sedimentary 

 formations from suspension or removal of deposits, in which he 

 has pointed out many of the breaks or gaps which occur between 

 older and younger rocks, caused either by the subsequent removal 

 of the intervening or missing beds, or because the older beds had 

 been raised above the sea during the deposition elsewhere of the 

 intermediate beds. Now it is well known that these breaks or gaps 

 are only local; and the remark has been already made that, if we 



