( 435 ) 



supporting the conception that tlie coalescence in the North Sea of the 

 Northern ice-stream with another coming from Britain, may have 

 caused a deflection in its course over the northern parts of our 

 country, and clianged its direction into one from North-West to Soutli- 

 East. Owing to this meeting of Scandinavian and British glacial flows, 

 an enormous ice mass tilled up the North Sea, in connection with the 

 ice-sheet extending over Holland, North Gei-many and the British 

 islands, the edge of which, as a high wall, faced the South. Accord- 

 ing to Klockmann, Wahnschaffe, Rutot and others, between this 

 wall of ice and the mountains of Middle Germany, Belgium, France 

 and the southern parts of England, the melting water rose several 

 hundreds of meters high, and in this water the deposition of the loss 

 took place. With regard to our country, I entirely agree with this 

 view. Tlie structure of the loss in the South of Limbourg decidedly 

 shows, in several places, its origin as a sediment deposited by 

 very slowly running water containing a large amount of drift- 

 ice, an opinion formerly advocated by Di*. A. Erens. In several loca- 

 lities of the Limbourg chalk-plateau (in the adjacent parts of Belgium 

 even as high as 300 M. above sea-level) erratics of Southern origin 

 are found in or were excavated from the loss, especially veined 

 quartzUes from the Ardennes, sometimes measuring 2 M. and even more. 



If thus we have to admit such an extensive and powerful ice-sheet 

 with considerable accumulation in the North Sea, — and at the same 

 time infer from the direction of the glacial striae on the rocky sub- 

 soil in North Germany, that one and the same glacial flow, owing 

 to local conditions, has taken at the same or contingent points very 

 different directions, deflecting even more than 90°, — I do not consi- 

 der it impossible that in its course over the Hondsrug, and in general 

 over the northern parts of our country, the direction of the glacial 

 flow may have deviated entirely from that of the flow passing 

 over the North of Germany. 



Taking into consideration the still very limited knowledge we possess 

 of our erratics, and in view of the arguments in favour of a secondary" 

 transport of perhaps the greater part of these stones, I consider the 

 suppositions which I advanced before, and which I have now somewhat 

 more developed, as to a possible modification of the direction of motion 

 of the Northern ice-sheet over our coiuitry, not only warranted but 

 necessary- as a working-hypothesis for further investigation. I doubt 

 whether Dr. Jonker himself will now still adhere to his belief that, 

 "in case this conception is the right one a great number of researches 

 into our ""Scandinavian diluvium"" would become doubtful and 

 it would be advisable at once to begin a revision". That Diluvium 



