BULL. GEOL. SOC. AM. 







VOL. 21, 1909, PL. 20 



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Figure 1. — The Natural Bridge across the Kicking Horse River, near Field, 

 British CoLUiiBiA^ seen from below 



(See text figure 6) 



Figure 2. — The Natural Bridge which Spans the Lamoille Riyer^ Yerjiont, at low 



Water 



The water flows under the ledge between 1 and 2. At 3 the stream flows over a fall into 

 a hasin (called the death pot) and reappears at 4 



ILLUSTRATIONS OF NATURAL ROCK BRIDGES 



