IP s t e I s i a 



other islands also, is essentially a mass of tilted 

 gneissic rocks with here and there certain terti- 

 ary areas. It was subjected to heavy glaciations. 

 The main course of the glaciers seems to have 

 been northward through the Straits of Georgia, 

 and westward, as shown by scourings on the 

 rocks around Victoria, through the Straits of 

 Fuca. The effect has been to leave in many 

 places extensive gravel moraines and in others 

 beds of boulder clay. On top of the sharply 

 tilted slate rocks of the region of the Minnesota 

 Seaside Station in certain j^laces are such mo- 

 rainic remains, while in others again the rocks 

 jut out bare, or have only such covering as 

 countless generations of decaying trees and other 

 vegetation have left behind. Along the shore, 

 on the projecting points mostly, there is super- 

 imposed upon the slate rocks a late sandstone 

 formation, while in the inlets there is usually a 

 coarse grained beach deposit, formed from 

 coarse sands and particles of the disintegrating 

 slate. The west coast, being subjected in many 

 places to unusually heavy wave action, is under- 

 going comparatively rapid changes. The geo- 



