The universal geography : earth and its inhabitants

102 SCANDINAVIA.the level of the lakes. But while they receive the overflow, these reservoirsdistribute it evenly amongst their outlets, reducing the amount of each during thefloodings, while husbanding the supply for the dry season. The annual variationof level in the lacustrine basins oscillates between 3 and 12 feel, although therise has occasionally been much greater, owing to the refuse blocking the outlets.Thus in 1795 the Vormen, which carries off the overflow of Lake Mjosen, wascompletely barred by fallen masses of rock, causing a rise of 22 feet in the level ofthe lake.The choking of the valleys at the outlets of the lakes has in many placesfacilitated the construction of dams, completely regulating the discharge accordingto the amount needed to drive the mills, or, in the season, for navigation.The floating ice also is seldom dangerous, owing to the southerly course of allthe large rivers. "When the thaw sets in the frozen masses are broken up first attheir mouths, and so on from south to north, so that no block takes place throughany sudden rush at the narrows.But although in other respects well regulated, the Scandinavian streams arenot generally available for navigation, except at a few points about their mouthsor in the neighbourhood of the lakes traversed hy them. The undeveloped stateof the river beds, still disposed in terraces, is favourable to industry hy affordinggood motive power, but not to traffic, which is interrupted by the rapids and dams.Many are so involved with successive falls and lakes, and even with other hasins,that they seem to have scarcely yet acquired a distinct individuality. Thus theTornea, on the Russian frontier, belongs really to two systems, one of its branches,the Tarando, flowing to the Kalix, the other to the Muonio. Many also ramifybeforereaching the sea, not sweepinground alluvial deposits, hut enclosing rockymasses, their branches being old marine channels converted into heds of runningwater. Such is the Gota-elf, whose hifurcation encircles the large island of Hisingen.The chief beauty of the Scandinavian rivers is due to their falls and rapids.On the Norwegian side all the streamlets may he said rather to he precipitatedthan to flow seawards. In many places there are clear falls of several hundredyards, and even some of the larger Norwegian rivers have sudden plunges of over300 feet. The Vorings-fos, near Trondhjem, descends at one leap 472 feet, andthe Rjukan-fos, formed by an affluent of the Skien-elv, in Telcmark, is precipitateda vertical height of 804 feet. Much lower in elevation, being only 70 feet high,hut far more considerable for the volume of its waters, is the Sarps-fos, on theGlommen, where even in winter a mass of 3,500 to 5,000 cubic feet, escaping fromits icy fetters, rushes hoadlong down a series of cascades, below which it againdisappears beneath the ice.Tho mean volume of the Sarp falls is about 28,000 cubicfeet per second, or double that of the Bhine at Schaffhausen. A recentlyconstructed railway bridge commands a full view of the entire series of cascades,and of the seething waters appearing here and there below tho dense vapours.Notwithstanding their proximity to Christiania, these Glommen falls, the mightiestin Europe, are less known than those of the Gota-elf, the famous Trollhiittan, or"Wizard's Cap," descending 110 feet in three successive leaps, and enclosinggrassy rocks between their rushing waters. The force of the Trollhiittan, estimated