208 Meserve — The Cham plain Submergence. 



brief description/ of what he believes to be a sea-cave, 

 formed during the Champlain period. This cave is 

 located on the southeast slope of Mount Ararat, a hill 255 

 feet high in the town of Topsham, Maine, mapped on the 

 Bath sheet, U. S. G. S. Topographic Atlas. As measured 

 several times by an aneroid, this cave stands 216 feet 

 above the present sea-level. The mouth of the cave is 

 about four feet in diameter ; the cave extends horizontally 

 into the rock for a distance of about fifteen feet. The 

 rock of Mount Ararat consists chiefly of highly metamor- 

 phosed quartzites and quartz-schists, with associated peg- 

 matites. 



In view of the fact that there is good evidence for the 

 former submergence of portions of the coast of Maine to 

 a depth of about 200 feet, it appears quite probable that 

 this cave was eroded by wave action. Two hundred and 

 sixteen feet can be assigned, then, as the depth of the 

 Champlain submergence in the Casco Bay region of the 

 Maine coast. 



BoTvdoin College, 

 Brunswick, Maine. 



