Professor Spencer — Continental Elevation. 37 



The Baltic valley hugs the coast of Norway, and beyond that it 

 extends to the same sea. From the col of the channel between 

 Faroe and Shetland, at a depth of somewhat more than 3,000 feet, 

 a great valley extends southward. North-west of Ireland, this 

 valley reaches a depth of 9,980 feet, upon the north-westward side 

 of which the plateau is characterized by shallow banks; and it 

 continues to a depth of 12,000 feet at the margin of the plateau. 

 Tributary amphitheatres to this great valley may be seen westward 

 of Ireland. One of these is 8,160 feet deep, where the platform 

 has been depressed 5,040 feet ; and two others have a depth of 

 10,500 feet, where the plateau is submerged only 4,000 feet. Further 

 southward, extending from the oceanic basin, a large embayment 

 indents and extends far into the platform south-west of Ireland, 

 having still a depth of 10,500 feet, where the shelf is covered by 

 only about 2,500 feet of water. The Bay of Biscay is a remarkable 

 embayment of great depth, with tributary amphitheatres like those 

 just mentioned. The amphitheatres mentioned have no extraordinary 

 widths. Their land equivalents are characterized bjf inconsiderable 

 streams descending precipitously over steps from plateaux of great 

 altitude. 



It is manifest, that Europe and Greenland form one continental 

 mass, while the latter country is separated by a much deeper sea 

 from the American continent. Accordingly, the search for these 

 drowned valleys should be made by means of numerous soundings 

 along lines parallel to the Iceland ridge, rather than off the coast 

 of Ireland. From the fragmentary knowledge already acquired, 

 it would be reasonable to expect the discoveiy of as complete 

 systems of river-valleys as those found off the American coast and 

 in the Antillean regions; indicating a late continental elevation of 

 12,000 feet or more. 



Continental Elevation a Cause for Glacial Climate. 



As has already been stated, the great continental elevation of 

 Eastern America occurred during the early Pleistocene period, and 

 was characterized by a stupendous amount of erosion, with the 

 production of carions and amphitheatres (at the heads of the valleys). 

 Such an elevation of two miles or more, as measured by the depths 

 of the valleys, must have produced a glacial climate in the more 

 northern regions of America and of the North Atlantic. Thus 

 we find a cause for the Glacial epoch; but many of the 

 phenomena cannot be considered here. Whether the elevations 

 of the North Atlantic and the American regions were absolutely 

 simultaneous, or compensated each other with altei'nations, like the 

 Antillean and Mexican undulations, is not known. Such altei'nations, 

 with their diversions of the oceanic and atmospheric currents, 

 together with the more recent partial submergence of the northern 

 lands, would pi'oduce variations of the glacial phenomena, and would 

 bring into close proximity those of high elevation and submergence, 

 and of warmer and colder climates. 



From as yet unpublished data, it appears that the late Pleistocene 



