forming the Lerfos, enter Trondhjem Fjord from the S., and range in
length from 70 to 100 m. The Stjördal, a beautiful wooded valley,
leads up from the fjord to the lowest pass over the Trondhjem
depression (at Storlien), and is followed by the railway from
Trondhjem into Sweden.
N. of Trondhjem Fjord, in spite of the close proximity of the mountains to the W. coast, several considerable rivers are found, flowing generally about N.E. or S.W. in valleys nearly parallel to the coast. Such are the Namsen (85 m. in length) and the Vefsen, discharging into Namsen Fjord and Vefsen Fjord respectively, and the Dunderland, flowing into Ranen Fjord. In the basin of the same fjord is the short Rös river, which drains Rös Vand, second in extent of the Norwegian lakes. In the extreme N., where the coastward slope is longer, there are such large rivers as the Alten, 98 m. long, discharging into the fjord of that name, and the Tana, also giving name to the fjord into which it flows, and forming a great part of the Russo-Norwegian frontier. It is 180 m. long, and drains an area of 4000 sq. m.
Though the lakes of Norway are not comparable with those of Sweden as regards either number or size, they are very numerous and are estimated to cover somewhat less than one-fortieth of the total area.
Glacial Action.—While the coast is considered to owe its fjords and islands to the work of former great glaciers, the results are even more patent inland. The actual tracks of the old glaciers are constantly to be traced. Nowhere are the evidences of glacial action better illustrated than in the barren tract behind the low coastal belt of Jæderen. Here are vast expanses of almost naked rock, often riven and piled up in fantastic forms; numerous small lakes or bogs occupy the rock basins, and vast numbers of perched blocks are seen, frequently poised in remarkable positions. The great valleys of Norway are of U-section and exhibit the irregular erosive action of the glaciers, as distinct from the regular action of the rivers. If a main glacier, after working steadily in the formation of its trough for a considerable distance, be imagined to receive an accretion of power at a certain point, it will begin from that point to erode more deeply. The result of such action is seen in the series of ledges over which the main rivers of Norway plunge in falls or rapids.
Geology.—Norway consists almost entirely of Archaean and Lower Palaeozoic rocks, imperfectly covered by glacial and other recent deposits. The whole of the interval between the Devonian and the Glacial periods is represented, so far as is known, only by a small patch of Jurassic beds upon the island of Andö. An archaean zone stretches along the W. coast from Bergen to Hammerfest, interrupted towards the N., by overlying patches of Palaeozoic deposits. Gneiss predominates, but other crystalline rocks occur subordinately. The Lofoten Islands consist chiefly of eruptive granite, syenite and gabbro. S. of a line drawn from the head of the Hardanger Fjord to Lake Mjösen is another great Archaean area. Here again gneiss and granite form the greater part of the mass, but in Telemarken there are also conglomerates, sandstones and clay-slates which are believed to be Archaean. Between these two Archaean areas the Lower Palaeozoic rocks form a nearly continuous belt which follows approximately the watershed of the peninsula and extends from Bergen and Stavanger on the S. to the North Cape and Vardo in the N. They occur also as a broad strip inlaid in the Archaean floor, from the Christiania Fjord northward to Lake Mjösen. A line drawn from the Nase to the North Cape coincides roughly with a marked change in the character and structure of the Palaeozoic beds. East of this line even the Cambrian beds are free from overfolding, overthrusting regional metamorphism. They lie flat upon the Archaean floor, or have been faulted into it in strips, and they are little altered except in the neighbourhood of igneous intrusions. W. of the line rocks have been folded and metamorphosed to such an extent that it is often difficult to distinguish the Palaeozoic rocks from the Archaean. They form in fact a mountain chain of ancient date similar in structure to the Alps or the Himalayas. The relations of the two areas have been studied by A. E. Törnebohm in the Trondhjem region, and he has shown that the western mass has been pushed over the eastern upon a great thrust-plane. The relations, in fact, are similar to those between the Dalradian schists of the Scottish Highlands and the Cambrian beds of the W. coast of Sutherland. In Scotland, however, it is the eastern rocks which have been pushed over the western. Corresponding with the difference in structure between the E. and the W. regions there is a certain difference in the nature of the deposits themselves. In the Christiania district the Cambrian, Ordovician and Silurian beds consist chiefly of shales and limestones. Farther north sandstones predominate, and especially the Sparagmite, a felspathic sandstone or arkose at the base of the Cambrian; but the deposits are still sedimentary. In the Trondhjem district, on the other hand, belonging to the folded belt, basic tuffs and lavas are interstratified with the normal deposits, showing that in this region there was great volcanic activity during the early part of the Palaeozoic era. In both the E. and the W. region the Devonian is probably represented by a few patches of red sandstone, in which none but obscure remains of fossils have yet been found. It may be noted here that in the extreme N. of Norway, E. of the North Cape, there is a sandstone not unlike the Sparagmite of the S., which is said by Reusch to contain ice-worn pebbles and to rest upon a striated pavement of Archaean rocks.
The Mesozoic era is represented only by the sandy deposits with seams of lignite which occur on the island of Andoën in the Vesteraalen. They contain remains of plants and have been correlated with the Lower Oolite of Great Britain. No Tertiary beds have been found, but Pleistocene deposits of various kinds are met with. The evidences of ice action during the Glacial Period are conspicuous over the whole country and are similar to those in other glaciated regions. But the most remarkable features produced in recent geological times are the terraces which appear as if ruled on the sides of the valleys and fjords. They are partly platforms cut in the solid rock and partly accumulations of gravel and sand like a modern beach, and they were evidently formed by the action of waves. Some of them contain marine shells of living species and mark the former position of the sea-level; but others are of more doubtful origin and may indicate the shores of lakes formed by the damming of the lower part of the fjords by means of glaciers, as in the case of the Parallel Roads of Glen Roy. They occur at various levels, and have been observed as high as 3000 ft. above the sea.
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| Emery Walker sc. |
No volcanic rocks of modern date are known in Norway, but great intrusions of igneous rock took place in early geological times. Amongst them may be mentioned the gabbro of the Jotunfjeld, and the elaeolite syenites and associated rocks of the Christiania region. The latter form the subject of a valuable series of memoirs by Brögger, who shows that they have all been derived from a single magma, and that the differentiation of this magma led to the production of several different types of rock. (P. La.)
Meteorology.—The most powerful influence on the climate of Norway is that of the warm drift across the Atlantic Ocean from the S.W. The highest mean annual temperature in Norway is found on the S. and W. coasts, where it ranges from 44·5° to 45·5° F., and the lowest is found at Karasjok and Kautokeino, lying at elevations of 430 and 866 ft. respectively in Temperature. Finmarken, near the Russian frontier. Here the mean temperature is 26·4°, while at Vardö, on the north coast, it is 33°. At Röros (2067 ft.) at the head of the Glommen valley, and at Fjeldberg (3268 ft.) in the upper Hallingdal, the mean annual temperature is 31°. The longest winter is found in the interior of Finmarken, 243 days with a mean temperature below 32° being recorded at
