THE GLACIAL PERIOD. 199 



rounded and striated rocks in the vicinity of Leipzig. A few 

 miles east and north of that town several bosses, knolls, and 

 rounded ridges of quartz-porphyry project for some 30 or 40 

 feet above the general level of the surrounding flat country, 

 which is everywhere clothed with boulder-clay and gravel. All 

 these prominent knolls have evidently been subjected to glacial 

 action, and show the characteristic rounded and smoothed 

 surfaces. Not only so, but in some places, as upon the hill 

 called Kleine Steinberg, there are polished faces exhibiting well- 

 marked parallel striae and grooves, which point from N.N.W. to 

 S.S.E. The boulder-clay of the neighboiirhood contains many 

 stones which could only have come from the north, and amongst 

 them are fragments of certain characteristic Scandinavian rocks. 

 Dr. Penck has also detected another similar knoll of porphyry 

 (Dewitzer Berg) near Taucha, eight miles distant from that just 

 referred to, which likewise shows a mammillated, polished, and 

 striated surface — the scratches agreeing in direction with those 

 upon the glaciated rocks nearer Leipzig. MM. Torell and 

 Helland, who visited this locality in company with Professor 

 Credner, agreed with him that the roches moutonndes, the polish- 

 ing and striation, were undoubtedly the work of land-ice, and 

 they had no difficulty in deciding from the position of the Stoss- 

 seite that the glaciating agent had flowed into Saxony from the 

 north-west. As to the character of the boulder-clay there could 

 be just as little doubt. It was as usual an unstratified mass, 

 crammed with angular and sub-angular stones, not a few of 

 which could be certainly recognised as of Scandinavian origin. 

 Credner, Torell, Helland, and Penck, were all agreed as to its 

 having formed the bottom -moraine of a mer de glace. More 

 recently glacial striae have been noticed on the Galgenberge 

 near Halle (on the Salle), and on the Eainsdorfer Berge, and the 

 Pfarrberg, near Landsberg. 1 



It is impossible to enter into details here, but I may refer 

 very briefly to certain other facts which serve to confirm the 

 view that the great boulder-clay deposits of Northern Germany 



1 0. Luedecke : Neues Jahrbuchfiir Mm. Geol. und Pal., 1879, p. 567. 



