PUTNAM 



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terraces adjacent to the shore. Shales, on the other hand, and especially those with a high con- 

 tent of volcanic ash, often fail through landsliding, as in the area near the center of the photo- 

 graph. Such ground is quite unstable for military operations. 



Figure 4 shows a mountainous coast in the same region. Here again are a set of operating 

 problems that we hope can be set forth in tabular form and that can be recognized by a relatively 



Figure 3. Stream-eroded complex hills, dry region. Coastal 

 terraces on Palos Verdes Hills, Southern California. (Spence 

 Air Photo) 



Figure 4. Stream — eroded complex mountains, dry region. Seaward 

 slope of Santa Ynez Mountains, Southern California. (Spence Air Photo) 



