126 W. H. HOBBS REPEATING PATTERNS IN STRUCTURE OF LAND 



ing by continental glaciers yield, on the contrary, relatively gentle curves 



*9^J^^^ ^-^ 



Figure 2, — Typical Fold Topography 



Note the curving zones of islands and the parallel water lanes which mark the 

 courses of stronger and weaker rock layers respectively. (From the Vaxholm sheet of 

 the topographic map by the Swedish General Staff.) 



■which are convex upward instead of concave and which are relatively 

 symmetrical {i, of figure 3). 



