PLATE XII. 



BLACK HILLS GEOLOGY. 



Fig. I. — View of the southwestern side of Ragged Top Mountain, 



showing the upturned strata on the west. 

 See page 214. 



Fig. 2. — Tracing made from figure i to show the relation of the 



upturned limestone to the phonolite of Ragged Top Mountain. 

 See page 214. 



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