576 
SUMMARY. 
1. From the shape of the rows of islands we may conclude that 
besides in a vertical direction they can also move largely in a 
horizontal direction. 
2. The geotectonic geology of ten dealt with as a part of descriptive 
geology, includes a number of problems which admit only a dynamic 
solution. 
3. Just as a glacier impresses us with the idea that it is perfectly 
quiescent, whereas the presence of crevasses can only be accounted 
for by velocity-differences of the movement, the much slower move- 
ment and the velocity-differences in the case of geanticlines can be 
demonstrated by the faults and fractures near the surface, and that 
especially there where erosion has exerted only little influence and 
only during a short period, as in the case of the geanticlines in 
deep seas. 
