Page:Quarterly Journal of the Geological Society of London, vol. 33.djvu/183

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AND CIRQUES IN NORWAY AND GREENLAND.
145

AND CIRQUES IN NORWAY AND GREENLAND. 145

is very strikingly exhibited at the upper end of the Kangerdlugssuak Fjord, where the mountains rise several thousand feet above the Inland Ice. Nowhere did I see mountains rising from it at any- great distance from its outer edge ; but it often happens that portions of land protrude like islands near the border of the sea of ice ; these, however, are not be regarded as insulated peaks rising above the ice, but rather as portions of the bordering land encircled by the Inland Ice or its dependent glaciers. They resemble in appearance the bordering land, and are called by the natives Nunataks, appen- dages to the land. For example, at Kangcrdlugssuak, where the mountains are lofty and the sides of the fjords steep, there are three Nunataks, also with steep nearly vertical sides, and equalling in height the neighbouring land ; but above the Inland Ice of Disko Bay, where the outlines of the land are less abrupt, the Nunataks are lower knolls.

I observed the Inland Ice most closely above Ilartdlek, near Pakitsok, during an expedition up it on July 17, 1875. Here the mountains rise some hundreds of feet above the Inland Ice, from which a huge glacier descends almost to the sea, probably through a valley in the mountain-ridge. By ascending a mountain on the left side of this glacier and then descending some three or four hundred feet, the surface of the Inland Ice may be reached without difficulty ; it forms here small undulating and gently sloping hummocks, on an average scarcely six feet high, and so is easily traversed ; there are but few fissures, and these narrow enough to be crossed without difficulty. Several rivers, however, flow over the suiface in various directions, some too large to be easily crossed. Their water is clear and free from mud ; they have excavated canal-shaped beds, the ice at the bottom being of a bluish colour. Their size doubtless depends upon the temperature ; and when it sinks to the freezing-point they probably vanish. On that day at 4 p.m., the air-temperature one and a half metre from the surface of the ice was 7° C. in the shade. The ice itself is granular at the surface ; but this structure extends to no great depth ; for, on cutting into it, compact ice, with air-bubbles, is soon found. The ordinary ice is often intersected by blue veins. Cones of sand and gravel with the usual icy cores occur near the border of the Inland Ice, also regular cylindrical holes of variable breadth up to one and half metre, filled with clear water and with a layer of clay at the bottom. Boulders and gravel are only found near the border of the Inland Ice ; along this was a small moraine scarcely six feet high, while that beside the glacier lower down was as much as 16 metres. The above description of the Inland Ice at Ilartdlek agrees in all respects with that given by Professor Nordenskjold of the Inland Ice above Aulatsivik (Auleitsivik) ; so that probably the same features would be found over the whole extent of the surface be- tween the two places, only interrupted by crevasses where the great glaciers descend to the fjords. The surface of these is often so much fissured as to be impassable ; the above crevasses, however, do not appear generally, so far as my experience goes, to extend very far up into the Inland Ice. It is very difficult, if not impossible, to