The universal geography : earth and its inhabitants

90 SCANDINAVIA.between "Wenersborg and Jonkiiping. Their levelled summits present tolerablyuniform surfaces, strewn witb boulders, with intervening swamps and lakelets.Still the aspect of the land is occasionally deceptive, and to glacial action bavebeen wrongly attributed certain parallel dispositions of rocks that bave been thusaffected by side pressure. The group of islands, for instance, immediately to thewest of Cbristiania, are all turned north-east and south-west, and are furrowed withcreeks and separated by channels all running in the same direction. But the striaoscored by the old glaciers are all at right angles to these parallel lines.Of more difficult explanation than the strice are the so-called a&ar, or lowridges of various heights, from 20 to 200 feet, stretching almost without interruptionsometimes for over 70 miles across the country, generally from northto south, or south-east, and winding like rivers to the right and left. Thereare some lateral &sar of less length ramifying in various directions, whereas thelarger ones run mainly in parallel lines. They were at first supposed to be vastmoraines, until Berzelius showed that there was no direct relation of cause andeffect between the asar and the glaciers.The ftsar, however, are composed of materials transported for a first stage bythe ice, and then borne farther by other geological agencies. After vast depressionshad been filled in with detritus by the frozen streams, the waters begantheir work, hollowing out enormous furrows in these masses, in which the boulderscontinually gravitated downwards, becoming rounded off by friction, or ground tosand and gravel. Such are the materials of which the Asar are composed. Erdmannsupposed that the larger ones were due to the action of the sea-waters, which withthe changes of level took up the stones of the moraines that had so far drifted withthe streams. Many of the stsar, notably that which runs immediately north ofStockholm, are doubtless covered with marine shells of the same species as those ofthe present Baltic Sea. But such deposits are quite superficial, and have beenformed during a temporary subsidence of the land after the glacial epoch.According to the materials of which they are mainly composed, the Asar arecalled either sandasar or rulktemsar (sand or shingle &sar) ; but all alike showevident traces of more or less rough stratification, such as is still constantly goingon in running water. There seem to be others, again, which rest on moraines—fresh formation superadded to the first. In some there occur certain funnel-likeformations (asgropar), cylindrical or elliptical, with a circumference of 300 yardsand upwards, and a mean depth of 10 to 68 feet, the bottom of which is filled withclays formerly deposited by eddying waters. In the Sttomsholm .is there arethirty-nine such funnels in a distance of about 84 miles, all apparently due to theaction of running waters, whose force was spent by the obstacles lying in theirway, and by the constant shifting of their beds. In Norway, where the slopes aremuch more abrupt, and where the water-courses are consequently less developedbetween the mountain cirques and the sea, the asar, here known as raer, are farless numerous than in Sweden, and seem to have been mostly confounded with themoraines. The Norwegian word aas is applied to all eminences, even to rockysummits.