102 H. REUSCH. GEOL. IÅGTT. I THELEMAEKEN 0. S. V. [No. 2. 1896.] 



The following flgures illustrate other geological and geo- 

 graphical details of the region. Some small isolated mountains 

 protruding from the bottom of the Hallingdal (fig. pag. 87) are 

 probably formed in that way, that the valley at some remote 

 period was eroded to a higher level than now. After a 

 standstill erosion was again powerful and made the present 

 bottoms of the valleys leaving only the isolated mountains. 

 Compare the old bottom of the Numedal where the two fowls are 

 flying in the figure pag. 35. 



Trykt den 9 mai 1896. 



