26 SIDNEY POWERS 



the south, with the contact striking nearly east and west. The dip 

 of the sandstone and basalt is variable owing to minor folds, but is 

 in general in a northerly direction about 20 . 



Egg Island and Egg Rock on the east consist wholly of red 

 sandstone, dipping northwestward about 15 . Pinnacle Island 

 consists of red sandstone on the south and basalt on the north, 

 dipping northwest at angles of 20°-40°. Pinnacle Peak consists of 

 basalt. 



Each of the islands is separated from the others by a fault, 

 and they are probably bounded on the north by a continuation 

 of the Gerrish Mountain fault. On each island the flows or sand- 

 stones dip northward, but at different angles. 



The basalt flows of the Five Islands were undoubtedly originally 

 connected with the flow on Gerrish Mountain and with those on the 

 Two Islands. They do not, however, appear to be directly con- 

 nected with the agglomerate and tuff which are exposed along the 

 shore. Probably the dike in Gerrish Mountain was the source 

 of most of the igneous material, part of which flowed out, and part 

 of which was blown out. The relative age of the pyroclastic 

 material and the flows could not be determined. 



[To be continued] 



