We, (CIGMAIS, ZINIO) SIPCOISIG SEV LOCK Sy DING: 735 
masses would be very likely to have similarly affected the strata 
of the Alps of Freiburg. In order to test this point I visited the 
Alps of Freiburg in the summer of 1893. We ought here to be 
able it was thought (1) to distinguish clearly between the 
“Freiburg”’ (exotic) and the normal ‘Helvetian”’ series and 
therefore determine by direct examination at the place of con- 
tact between the two kinds of rocks whether the Freiburg strata 
show evidence of an overthrust southward upon the Swiss chains 
as we had been led to assume was the case with the cliffs. The 
results of these investigations, published elsewhere,” showed 
evidence of an overlapping of Freiburg strata southward 4.5 
kilometers upon normal and characteristic Helvetian beds, which 
were disclosed in the deeply cut valleys of the upper Simme and 
Saane rivers. Here, too, we find the same sharp contrast 
between the excessively disturbed and often inverted Freiburg 
strata and the horizontal Helvetian series that we noted in the 
cliff zone to the east; also similar breccias occur on the plane of 
overthrust. Here, too, as in the vicinity of Iberg, the overthrust 
is everywhere over the Flysch, so that the time of the movement 
corresponds to the time of movement farther east. 
Another feature which favors the view of overthrust from the 
north is to be found in the peculiar distribution of the exotic 
material over the belt occupied by the cliffs. Here I cannot 
perhaps do better than to refer to the accompanying sketch map 
where this feature is indicated, and point out what the map 1s 
intended to show. 
EXPLANATION OF THE SKETCH MAP. 
The map of North Switzerland shows the distribution of the 
cliff masses and ‘exotic blocks” of North Switzerland in the 
cliff zone extending from Lake Thun to the Rhine and the rela- 
tion of this cliff zone to the surrounding country. All portions 
colored black, either solid or diagonally striped, represent exotic 
material. The size of these masses has been necessarily exag- 
gerated in the map, though the relative size of the different 
* Berichte der naturforschenden Gesellschaft zu Freiburg in Baden, Vol. 
1IWo5 ING@s Bo 
