Page:Quarterly Journal of the Geological Society of London, vol. 33.djvu/208

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170
AMUND HELLAND ON THE FJORDS, LAKES,

170 AMUXD HELLAXD ON THE FJORDS, LAKES,

but as this situation is not absolutely the same in all valleys, we find some difference in their distances from the sea. Further, it is evident that the glaciers had retired from many fjord-valleys dis- tant from the mountain-region by the end of the Glacial epoch ; and in these we only find terraces, not lakes and moraines, near the sea. On the other hand, in some valleys the glaciers went further out into the fjords, and deposited their moraine on the bottom of the sea, so that the lake-basins are now pans of the fjord itself and have no separate existence.

We can constantly explain the Glacial phenomena of Xorway by reference to Greenland. The ice in the latter country is not now at its greatest extent ; so that Greenland at present affords us a picture of Xorway about the end of the Glacial epoch, when the glaciers in some cases extended out into the fjords, in others formed the lakes mentioned above. So that, according to our theory, lake- basins must exist in many places under the glaciers in the ice-fjords of Greenland, if only the latter have been for a sufficient time in their present position. It is, of course, very difficult, if not impos- sible, to observe these basins ; but I can bring an instance from near the ice-fjord of Torsukatak, which makes it probable that such basins exist, and will appear when the glaciers retreat. The glacier in the above fjord descends into the sea in four arms. The northern of these is separated by a mountain-range from a valley which lies symmetrically with them. In this there is at the present time no glacier ; but a lake begins near the sea called Amitsok, at the side of which are the remains of a lateral moraine, like those met with along the glaciers of the ice-fjords. This moraine shows that the valley has once formed a fifth arm of the glacier, which has now disappeared, leaving a lake in its track. This lake is about 20 metres above the sea, and less than a kilometre from it. I do not know its exact length, but think it is more than 7 kilometres.

To return to Xorway. The mode of occurrence of many lakes in South-eastern Xorway, if possible, still better illustrates their for- mation. On the east side of the Christiania Fjord, from Moss to Fredrikshald, and on the opposite side from Horten to Laurveg, lie two rows of moraines ; these indicate a limit of the glaciation of Xorway. While moraines in the narrow fjords in different valleys are quite separated by high mountain-ranges, here, where the ground is lower, they can be followed continuously over long dis- tances. Thus the rows of moraines extend, with some interruptions, for a length of 60 kilometres on both sides of the Christiania Fjord. Behind these are sixteen lakes, ten on the east and six on the west side of the fjord, lying on the line of the long moraines. I have visited all, and can directly demonstrate that most of them are true rock-basins. If, then, they are older than the Glacial epoch, it is a strange thing that the ends of all lie in the lines of the moraine, that the glacier advanced just as far as their southern ends, and that their longer axes are perpendicular to the line of the moraine. The phenomena are so regular that one might suppose that Professor Ramsay had propounded his theory of the Glacial formation of lakes