TJ. S. GEOLOGICAL SURVEY 



Bl'LLETIX 707 PLATE XLVII 



A. NATURAL GRANITE MONUMENT. 



This striking remnant of massive granite at the upper end of AVildhorse Canyon stands to tlie 

 right of the tracks and is at least 60 feet high. The granite is cut by dikes of other material, 

 which show in the picture. Photograph by Marius R. Campbell. 



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POTHOLES IN CRAMTE BOULDERS. 



In Brown Caiiyoti there are many large granite boulders around which in ordinary stages the water 

 swirls and boils but which in floods are completely submerged. The rushing current rolls round 

 and round small boulders caught in hollows of the larger blocks, cutting great circular pits called 

 potholes. Photograph by IMarius R. Campbell. 



