662 KEPORT — 1901. 



of the comparatively sliallow Nortli Sea, aucl we have to consider why it is 

 that they are untraceable. 



The cause appears to he closely connected with the suhsequent submergence in 

 later or Post-Glacial times, as indicated by the raised beaches and terraces.' 

 During- this epoch the glaciers had only partially disappeared or receded from the 

 lower valleys. Great quantities of mud, saud, gravel, aud boulders would be 

 carried down by the streams and distributed by floating ice over the sea-bed. 

 By such material the whole floor of the North Sea has been overspread to 

 unknown depths, and owing to the agency of tides and currents would have been 

 swept into the deep channels of the pre-existing rivers. The author is convinced 

 that were it possible to strip the floor of the North Sea of its sedimentary cover- 

 ing these channels would be found traversing the floor of the continental platform, 

 aud ultimately opening out by canon-like channels on the floor of the Arctic Ocean. 



The phenomena here observed, or inferred, have their representatives along the 

 coasts of the British Isles and Western Europe. In both cases there is the 

 shallow continental platform, terminating in a deep aud rapid descent to the 

 floor of the abyssal ocean, and traversed by channels of ancieut rivers traceable 

 by the soundings in the case of Western Europe, or inferential in the case of 

 Western Scandinavia. In a few cases these channels are for short distances 

 clearly indicated on the charts, as, for example, in the case of the BredsundDybet, 

 which is a prolongation of the Stor Fjord out to sea, between the islands of Godo 

 and Harejdo in lat. 62'' 30', with a general depth of 100 fathoms below the 

 adjoining floor of the sea ; and there are a few other similar cases. 



Outline of the physical history of the fjords. — As connected with the past 

 history of the Norwegian Ijords the following appear to be the most important 

 stages : — 



1st (Earliest) Period. — Continental conditions; Archfean rocks; river 

 erosion begins. 



:2ud Period. — -Partial submergence in early Silurian times. 



;3rd Period.— Elevation of land during Mesozoic aud Tertiary periods; farther 

 deepening of river channels. 



4th Period. — Quateruary. Early Glacial ; great elevation of land and 

 ultimate extension of snowflelds and glaciers. Ice filling the valleys and moving 

 out to sea. 



5th Period. — Quaternary. Post-Glacial ; subsidence and partial submergence 

 of land ; retreat of the glaciers. Icebergs and I'afts covering the adjoining sea. 

 Amelioration of climate. 



6th Period. — Recent. He-elevation to apprcximately present position with 

 regard to the outer oceau. Formation of raised beaches (strand linien). 



The paper concluded witli a comparison between the above physical features 

 as they occur in Norway with those of Scotland. 



5. On the Origin of the Gravel-flats of Surrey and Berkshire. - 

 By Horace W. MoncIcton, F.L.S., V.P.G.S. 



On the south of the Thames flat expanses of gravel are largely developed. 

 They lie at various levels from 600 feet O.D. at Ctesar's Camp, Aldershot, down 

 to almost sea-level in the Thames valley uear London. 



The oravel is of variable thickness ; jierhaps 15 feet is about the average. 



There are similar gravel-flats north of the Thames, but there drift questions 

 are complicated by the presence of glacial beds. 



' According to Professor Eeusch the terraces with marine shells reach an eleva- 

 tion of about 200 metres (620 feet) in the Trondheim district; but the author 

 during a recent visit was unable to observe any higher than 250 feet south of this 

 position. 



- Published in full in the Geological Magazine, December 4, vol. viii. November 

 1901. 



