EEADFIELD-BKUi^SWKJK SYSTEM. 189 



are frontal plains of glacial sediments, l^ut all together make out a strong 

 case. Eveiy time I review the subject I am more impressed with the weight 

 of this cumulative evidence. 



All the facts so far as known indicate that the short eskers and osars 

 of northwestern Maine are a feature of the very last part of the glacial 

 epoch, when the ice had retreated as far north as this region, and the 

 glacial rivers were consequently rather short. 



READFIELD-BRUNSWICK SYSTEM. 



This interesting system begins 2 miles northeast of Readfield Village 

 as a low ridge of rather fine subangular gravel, which extends about 1 mile 

 south to Lake Maranocook. No glacial gravel is known to appear on the 

 shore of this lake until we reach Winthrop Village The eastern part of the 

 barrier which separates the upper and lower Winthrop lakes is underlain by 

 rock at a depth of a few feet. Along the line of the Maine Central Rail- 

 road, in the western part of the village, is a north-and-south valley extend- 

 ing from one lake to the other. The surface of this valley rises about 20 

 or 25 feet above the upper pond, and wells show it to be covered by glacial 

 sand and gravel, flanked by sedimentary clay, to a depth of more than 40 

 feet. Evidently the preglacial drainage flowed along- this valley, and the 

 barrier of sand, gravel, and clay which now separates the ponds dates from 

 glacial time, or in part was contemporaneous with the sea. In several 

 j)laces in Winthrop Village and the vicinity marine fossils have been found 

 at an elevation of 200 to 214 feet. Probably the plain which separates the 

 uj)per and lower ponds was a delta-plain, deposited in the sea by a small 

 glacial stream from Readfield. 



About three-fourths of a mile south of Winthrop Village, on the west 

 shore of the lower pond (Lake Anabescook), is a short ridge of gravel and 

 well-rounded cobbles, which at one place rises into a cone or mound 30 

 feet high. This ridge has been extensively excavated by the railroad com- 

 pany. Then there is an apparent gap in the system till we reach the 

 south end of the lake. Here a short distance north of East Momuouth, on 

 top of hills rising 50 to 100 feet above the lake, is a capping of glacial gravel 

 one-third mile long from north to south and not quite so broad. The gravel 

 is a rather round-topped plain, divided along the center by a narrow north- 

 and-south ravine, which does not reach to the bottom of the g-ravel. No 



