90 SCANDINAVIA. 



between Wenersborg and Jonkoping. Their levelled summits present tolerably 

 uniform surfaces, strewn witb boulders, witb intervening swamps and lakelets. 



Still the aspect of the land is occasionally deceptive, and to glacial action have 

 been wrongly attributed certain parallel dispositions of rocks that have been thus 

 affected by side pressure. The group of islands, for instance, immediately to the 

 west of Christiania, are all turned north-east and south-west, and are furrowed with 

 creeks and separated by channels all running in the same direction. But the striae 

 scored by the old glaciers are all at right angles to these parallel lines. 



Of more difficult explanation than the striae are the so-called asar, or low 

 rido-es of various heights, from 20 to 200 feet, stretching almost without inter- 

 ruption sometimes for over 70 miles across the country, generally from north 

 to south, or south-east, and winding like rivers to the right and left. There 

 are some lateral asar of less length ramifying in various directions, whereas the 

 lart^er ones run mainly in parallel lines. They were at first supposed to be vast 

 moraines, until Berzelius showed that there was no direct relation of cause and 

 effect between the asar and the glaciers. 



The asar, however, are composed of materials transported for a first stage by 

 the ice, and then borne farther by other geological agencies. After vast depres- 

 sions had been filled in with detritus by the frozen streams, the waters began 

 their work, hollowing out enormous furrows in these masses, in which the boulders 

 continually gravitated downwards, becoming rounded off by friction, or ground to 

 sand and gravel. Such are the matei'ials of which the asar are composed. Erdmann 

 supposed that the larger ones were due to the action of the sea-waters, which with 

 the changes of level took up the stones of the moraines that had so far drifted with 

 the streams. Many of the asar, notably that which runs immediately north of 

 Stockholm, are doubtless covered with marine shells of the same species as those of 

 the present Baltic Sea. But such deposits are quite superficial, and have been 

 formed during a temporary subsidence of the land after the glacial epoch. 



According to the materials of which they are mainly composed, the asar are 

 called either sandasar or ruUstenusar (sand or shingle asar) ; but all alike show 

 evident traces of more or less rough stratification, such as is still constantly going 

 on in running water. There seem. to be others, again, which rest on moraines — a 

 fresh formation superadded to the first. In some there occur certain funnel-like 

 formations (asgropar), cylindrical or elliptical, with a circumference of 300 yards 

 and upwards, and a mean depth of 10 to 68 feet, the bottom of which is filled with 

 clays formerly deposited by eddying waters. In the Stromsholm as there are 

 thirty-nine such funnels in a distance of about 84 miles, all apparently due to the 

 action of running waters, whose force w^as spent by the obstacles lying in their 

 way, and by the constant shifting of their beds. In Norway, where the slopes are 

 much more abrupt, and where the water-courses are consequently less developed 

 between the mountain cirques and the sea, the asar, here known as raer, are far 

 less numerous than in Sweden, and seem to have been mostly confoimded with the 

 moraines. The IN^orwegian word aas is applied to all eminences, even to rocky 

 summits. 



