336 ON DRIFT ICE AS AN ERODING 



covered even by spring tides. The first appearance of " Mad 

 Moll" was a noteable event in the life of the preceding genera- 

 tion. The north or main passage of Sandwick Bay, not many 

 years ago navigable for small vessels, is now impassable for any- 

 thing but boats At Mullen's Cove and Black Island, raised 

 beaches are seen composed almost entirely of mussel shells, some 

 of them unbroken and clean as if thrown up yesterday. These 

 shell deposits are of course seen only in the more sheltered coves 

 where they are protected from the grinding action of drift ice. 

 The rate of elevation here indicated is considerably greater than 

 some recent estimates, and I would like to hear new evidence on 

 this point. 



One noticeable point is, that the hillsides above the escarp- 

 ments show the same smooth and storm-swept appearance as 

 between and below them, as if they had been subject to the same 

 influences and wear by drift ice. Whether the upper escarp- 

 ment marks the limit of subsidence or not, the natural inference 

 seems to be, that a gradual and regular elevation of a sloping 

 exposed surface, especially when comparatively rapid, leaves no 

 traces of ice action. The retiring sea and ice washes off and 

 carries to lower levels the debris formerly covering the solid 

 rock. Only when the downward movement is arrested, does it 

 form escarpments and beaches, and the fact that no escarpments 

 nor beaches are seen above the highest shore line is no proof 

 that the sea level had not once been higher. Neither on nor 

 around any of the hills near Battle Harbor and Cape Charles 

 (some of which are 700 feet high), is there any sign of glacial 

 debris ; and had it once been there it does not seem possible 

 that either land-slides or fluvatile action could have banished it 

 so thoroughly from both hill and valley. 



The raised beaches are seen only in sheltered bays where not 

 exposed to the possibility of being swept away by water or 

 landslides from above, or intense ice action from the sea below. 



A. C. Low, from observations on Hudson Straits, supposes 

 that part of the coast to have come to a standstill. But on the 

 Straits of Belle Isle the last escarpment seems to be rapidly 

 advancing beyond the level of mean tide. 



