Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/940

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of various materials ; 2. That particular materials must predominate in particular localities ; 3. That the bottom in the vicinity of ice- fjords and in fjords must be chiefly composed of clay, with boulders, gravel, and earth either scattered over it or in patches ; 4. That the mouth and centre of Davis Strait and various banks, such as Rifkol, must be chiefly composed of earth, gravel, boulders, &c, with little or none of the glacier-clay ; 5. That life must not be uniformly distributed through this bottom ; 6. That though the lines of travelled blocks, boulders rubbed by grounding bergs, ice, or by being brought out as part of the moraine profonde, will be found scattered over every portion of the sea, still they will chiefly be found in the lines of fjords and of the iceberg-stream ; 6. That the clayey bottom of deep inlets will be little disturbed, while that of shallow ones will be grooved and torn up by grounding bergs, &c.

III. Rise and Fall of the Greenland Coast.

It may be asked — have we any data for the conclusions in the foregoing paragraphs, further than logical inferences from observed facts justify us in drawing ? Yes, we have ; for there has been a rise of the Greenland coast, laying bare the sea-bottom, as just now there is a fall going on. This fact is not new ; on the contrary it is notorious, but has been much misunderstood. We have the Danes telling us on the most irrefragable evidence that the coast is falling, while the Americans who wintered high up in Smith's Sound, saw there raised sea-beaches and terraces, and accordingly say that it is rising in that direction, while in truth, both of them are right, but not in the exclusive sense they would have us to imagine. There has been a rise ; there is a fall going on. We now supply the proofs.

1. Rise. — In Smith's Sound both Kane's and Hayes's expeditions observed a number of raised terraces 110 feet above high tide-mark, the lowest being 32 feet. These were composed of small pebbles, &c. Hence they concluded that the coast was rising. I think it can be easily enough shown that this is only a portion of the old rise of the Greenland coast. The interval between this locality and the Danish possessions, commencing at 73° N. lat., has been so little examined either by the geographer or the geologist that we can say nothing about it ; but more to the south and along the whole extent of the Danish colonies, this raised portion of the sea-bottom is seen. The hills are low and rounded, and everywhere scattered with perched blocks, boulders, &c, many of them brought from northern or southern localities. In other localities, in the hollows or along the sea-shore, we see several feet of the glacier-clay (the " brick-clay " in fact) full of arctic shells such as are now living in the sea, Echinodermata, Crustacea, &c, while in other places, as might be expected from what I have said, the clay is bare of life. This clay corresponds identically in many places with some of the " brick-clays " of Scotland, though, as might be expected from the difference these clays partake of from the different rocks the trituration of which has given origin to them, they are in some places of different shades of colouring. In this