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M. L. FULLER 



perfectly smooth surface, but is characterized by broad, gentle undu- 

 lations, merging into kettles about the margins. Some parts, however, 

 are as flat as a floor. In the southern half of the lakelet the plains 

 are generally quite broken, though occasional flat-topped areas exist. 

 The margins of the plains nearest the valleys present in both areas 

 the same gradational type as the East Sharon plains. 



The natural outlet of the Stoughton lakelet would at first sight 

 appear to have been southward along the valley followed by the rail- 

 road, or along the similar valley half a mile farther east. The alti- 

 tude of these outlets in each instance, however, is less than 200 feet, 

 while the flat tops of the sand plains, which probably indicate the 

 approximate level of the water of the lake, is 250 feet, or the same 

 as that of the Rattlesnake Hill and East Sharon deposits. It seems 

 clear, therefore, that the southward valleys mentioned were still 

 blocked by the ice. The elevations of the Stoughton plains, corre- 

 sponding as they do with that of the Rattlesnake Hill outlet, suggest 

 that it was through this notch that the water passed on to the south. 

 To do this it must have crossed the tongue of ice still occupying the 

 valley north of Ames Pond. An examination of the locality seems 

 to show beyond reasonable doubt that this was in fact the case, the 

 waters crossing just north of the road leading eastward from near 

 Dry Pond. The waters in passing deposited much material on the 

 ice, which, on the melting of the latter, was left as an irregular belt 

 of sands, gravels, etc., across the vafley at the point indicated, and 

 practically connecting the Stoughton with the East Sharon plains. 



LATER OR SPRINGDALE STAGES. 



Elm Street lakelet. — This lakelet came into existence after the 

 ice-margin had melted back to a point a mile or more to the west 

 of the position it occupied during the deposition of the Stoughton 

 plains. The lakelet proper was about three-quarters of a mile wide 

 from north to south, and a mile from east to west. In it was deposited 

 the typical flat-topped plains traversed by Elm and Water Streets 

 about a mile southwest of Stoughton. Its upper surface stands at an 

 elevation of 210 feet, and the plain is bounded on the northeast, 

 north, and west by sharp ice-contact slopes, while on the east and 

 south it slopes off into rolling deposits, apparently quite distinct from 



