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tion southward past the west side of Prospect Hill of the 

 valley of Beechwood River, and through which, it seems 

 probable, the waters of Liberty Lake found an outlet. The 

 eskers form two adjacent and approximately parallel ridges 

 from 20 to 40 feet high immediately west of and parallel with 

 Prospect Street, commencing at the bend in the street south of 

 Beechwood River and extending in a south-southeast direction 

 across the town-line into Norwell as far as Valley Swamp, the 

 extreme length being nearly half a mile. The western ridge 

 reaches a little farther north than the other, and both are some- 

 what serpentine, being separated by shallow kettles, and uniting 

 at one point to form for a few rods a single ridge. 



That these eskers are connected in origin with a glacial river 

 flowing southward through this valley there can be but little 

 doubt. The whole appearance of the valley, east of Prosj)ect 

 Street, indicates that it has been swept by such a current. 

 The very broad, low hill of till extending from Prospect Hill 

 southwest to Valley Swamp is thickly strewn with bowlders, 

 the finer portion of the till having been washed away ; and on 

 the lower western and southwestern slopes of Prospect Hill, as 

 previously noticed, the ground is literally covered with bowlders, 

 especially on the erosion terraces, which are a conspicuous 

 feature of this drumlin. The most prominent bench or terrace 

 is from 45 to 50 feet below the summit. It is strongly marked 

 and continuous along the entire southwest side of the hill. About 

 30 feet below this is a second terrace ; and 20 feet below that 

 a third, the latter agreeing approximately in elevation with the 

 kames and Liberty Plain. The up])er terraces, at least, must 

 antedate Liberty Plain, requiring the same explanation as the 

 similar terraces on the drundins of Cohasset and Nantasket ; and 

 thus dating from a time when the ice-sheet filled this valley, 

 with the top of the drumlin protruding and a glacial river 

 running between the slope of till and the edge of the ice. 



The distinctly double or duplicate character of the Prospect 

 Street eskers is very suggestive of the material having been 



