OUR GREATEST NATIONAL MONUMENT 



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Photograph by Frank I. Jones 



A STREAM FROM A HOT SPRING MADE THIS NATURAE BRIDGE OF SNOW 



Hot water emerges from many openings in the valley leading up to Katmai Pass. These 

 ancient hot springs were well known to the natives. They constituted almost the only sign of 

 volcanic activity in the district before the eruption of 1912. 



of gas from the substance of its solid 

 components. 



After the forward motion had ceased, 

 explosions continued for a time, tearing 

 great yawning holes in the surface of the 

 smooth valley floor — the present craters 

 which dot its surface. Some of these are 

 isolated ; others stretch out in long lines 

 like beads on a string, indicating prob- 

 ably the seat of fundamental fractures in 

 the rocks beneath. In other places they 

 are so thickly peppered over the surface 

 as to coalesce and form compound nests 

 of craters. Two of these measure half 

 a mile in diameter (see page 246). 



The explosions responsible for the val- 

 ley craters were insignificant in violence 

 as compared with the great outbursts of 

 Katmai, for all the debris fell in the im- 

 mediate vicinity, no recognizable quantity 

 having reached the sides of the adjacent 

 mountains. Still, explosions capable of 

 tearing up pieces of ground half a mile 

 square and upheaving them in a series of 

 fountains of red-hot rocks thrown in all 

 directions would, from the human stand- 

 point, form about as awe-inspiring an 

 exhibition of titanic forces as can well 

 be imagined. 



The fiery flow at its height must indeed 



