Sources of Materials. 19 



rising slowly above the ocean. This change 

 of level has been going on for thousands of 

 years and has lined both the Baltic and At- 

 lantic borders with elevated beach terraces 

 showing stage after stage of successive eleva- 

 tions, all geologically recent. The rate of 

 this elevation is stated by government author- 

 ity as amounting to five or six feet in a cen- 

 tury at the North cape, while less than this 

 southward. A still more impressive group 

 of such facts may be gathered from our own 

 Pacific coast. Hundreds of miles of these 

 elevated beaches have been observed and care- 

 fully surveyed along the coast of South Amer- 

 ica; but we leave these to fix our attention 

 upon our own home share of such world facts. 

 For this purpose we select four points of ob- 

 servation along our own coast as exhibiting 

 such recent elevated sea beds to a striking 

 extent. 



At Cape Blanco, near the lighthouse, one 

 may see an old sea beach elevated two hun- 

 dred and ten feet above tide water, in which 

 shells, for the most part like those now living 



