THE WORK OF THE OCEAN 



305 



is composed and the rapidity of the cutting. Rapid cutting and 

 resistant material tend to produce steep cliffs; but incoherent 

 materials, such as sand and clay, may form steep cliffs if the cut- 



Fig. 251. A chimney rock and an arch on the coast of France. (Neurdein.) 



Fig. 252. Chimney rocks, etc., developed by wave erosion, Coast of Cali- 

 fornia. (Fairbanks.) 



