CHAPTER VI. 

 THE SHOSHONE ISLAND. 



Thus far our attention has mainly been 

 occupied on the western or Siskiyou island; 

 we have now reached a point in our narrative 

 at which the other island calls for some notice 

 of the features specific to its region. 



The outlines of this Shoshone island, like 

 those of the Siskiyou of the Cretaceous period, 

 are in part suggested by the back-lying ridges 

 of the changed older rocks, and partly by the 

 uplying surface of the Cretaceous shore line. 

 One sees a fine exposure of this Cretaceous 

 at old Camp Drake in the Crooked River val- 

 ley, which plainly was once part of the shore 

 line of the western spur of the Shoshone is- 

 land. A like stretch of the northern shore 

 line of the same spur may be seen in several 

 localities in the John Day valley one of these 

 on Rock creek and Spanish gulch east of old 



