116 A STUDY OF THE COW BAY BEACHES D. S. McTNTOSH. 



indeed, surprising, at first glance, to see boulders of compara- 

 tively small size unmoved from the wave-swept drumlinbase. 

 This is owing, however, to the shallowness of the bay for 

 some distance seaward. In heavj^ storms, a line of breakers 

 is formed off-shore, and the force of the waves diminished. 



Origin of the Beaches. 



The material of which the beach is composed came from 

 the easily-eroded glacial mounds, and appears to have been 

 carried largely towards the west. On the seaward side of 

 the present beach were at least two islands C and D (Fig. 3). 

 It is not unlikely that between B and C were one or more 

 small islands further seaward that protected the island in 

 the pond from the waves before the beach was formed, and 

 which were early destroyed. While the drumlins A and E 

 extended further seaward than today, the islands were 

 more sheltered than later. The on-shore storms would, 

 however, act upon them, and their reduction was begun. 

 With shallow water, as todaj^, and a current along the shore, 

 the tendency would be for the waste from the drumlin- 

 heads to be carried in the direction of the current, and to 

 form bars which might eventually tie the drumlins, as in 

 Fig. 3. As the waves cut back the drumlins, these beaches 

 would be driven further towards the pond-head. There was, 

 probably, a channel kept open by the currents for some 

 time between B and C, but this was gradually driven towards 

 the western end of the beach, until at length the water from 

 the pond emptied into the lagoon. When the drumlins 

 were consumed, or but shreds remained on the rear, the 

 beaches were located slightly seaward of the oldest old beach 

 of today. So much material had by this time accumulated 

 that, under ordinary conditions, the movement of the beaches 

 landward was ended. A violent storm, probably accomp- 

 panied by a high tide, next swept the shore. Its work was 

 most effective in the wider space between B and C, and 



