Page:Quarterly Journal of the Geological Society of London, vol. 33.djvu/200

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162
AMUND HELLAND ON THE FJORDS, LAKES,

162 AMUMD HELLAND ON THE F JORDS, LAKES,

this glacier was 240 metres above the sea, and the top of the moun- tain 1207 metres. The steep, often almost vertical, walls which enclose a cirque frequently approach each other near the mouth, so that a horizontal section is more than a semicircle. In many- cirques the floor is occupied by a glacier ; in other cases there is often a little lake in the middle, with a moraine in front of it. The ground is commonly covered by large shattered blocks which, near the opening, often, if not always, are collected into a moraine.

Cirques are numerous among the peaks of the Jotunfjclds, the loftiest mountains of Norwa} On Glittretind and Nautgarstitid they occupy half the side of the whole mountain, its physical fea- tures being due to them. The large and beautiful cirque on Glit- tretind is thoroughly typical. The uppermost part of this moun- tain consists of a semicircular crest, which slopes comparatively gently to the southern or outer side, whilst on the northern or inner side it descends precipitously into a horseshoe-shaped valley or cirque. The mountain is thus in form a cone, from a side of which an enormous cylindrical space has been excavated. The floor of the cirque is covered by a glacier, and. cliffs rise above it to an estimated height of more than 350 metres, the summit of the crest being 2554 metres above the sea. Another interesting case occurs in tho mountain Togga, in Sogn, where four cirques lie one beside another, like four horseshoes placed in a row. To these descriptions many others might be added ; but as their form and mode of occurrence is everywhere the same, both in Greenland and Norway, we may pass on to examine their geographical distribution. Mr. Bonney* and Professor Gastaldif have described the cirques of the Alps, and show that they resemble those in Norway. According to Mr. Drew, cirques occur in the Himalayas, where also they are often filled by glaciers or contain lakes. Professor Nordenskjold has mentioned their occurrence in Spitzbergen.

A striking feature about them in Norway is, that they occur in parts of the country where glaciers are now or have been at work in the modern period — as, for example, near to the Justedalsbrseen, the Folgefonden, and in the Jotunfjelds (Finmarken); in short, cirques are numerous in regions where small isolated glaciers now occur. Further, if we examine a landscape in which cirques abound, and count how many of them look towards the north and how many towards the other points of the compass, we find that the greater number open towards the north, north-east, and north- west, while but a few look towards the south or are situated on that side of the mountains. This can even be seen in a good map. When standing, for example, on the summit of Glittretind and looking towards the south-west and south-east, we see no less than twenty- one cirques opening towards the north, but none towards the south. Out of thirty-seven cirques in the Jotunfjelds, twenty-five have their openings toward s some point of the horizon between north- west and north-east, three between north-west and south-west,

  • Quart. Journ. Geol. Soe. vol. xxvii. p. 312.

t Ibid. vol. xxix. p. 393.