20' GUIDE TO LOCALITIES. 



at the Boston and Albany railroad track gives a cross-section profile 

 unexcelled in symmetry. Farther on, the sudden rise and fall of 

 the crest just before Beacon street is reached are independent of 

 the surrounding topography. 



The esker ends about here, which is near the station of Wood- 

 land ; but its original limits have been effaced by the construction 

 of new roads. Two sand-plateaus are near. On the right, one 

 extends westward to the Charles river, and holds at its south- 

 eastern edge the village of Newton Lower Falls. The ice-contact 

 slope has been cut partly away, but ran from north to northwest, 

 on the west side of Beacon street. The frontal lobes extend to 

 the Charles river. The delta is chiefly of interest in having three 

 distinct levels. On the left, and coalescing with the former for a 

 short distance directly along the street, is the Waban plain, which 

 stretches eastward from Beacon street past the Waban station. 

 On its surface, near this station and north of the road between 

 the two points just mentioned, is an interesting kettle hole. The 

 detritus around it grows steadily coarser up to its edge, showing 

 feeding from the melting of a block of ice which was never 

 completely covered. If the railroad track be followed from Waban 

 to Woodland, a large borrow-out shows one or two features, and 

 once showed many more. At its nearer (east) end, on the south 

 side , the faint outline of an esker can be seen, buried by the Waban 

 plain. Talus has nearly obliterated the view of it. At the far- 

 ther end of the cut, near Beacon street, is the section of a kettle 

 hole whose ice was buried, as was shown by the inclination of the 

 strata on its sides when the cut was fresh. The ice-contact ran 

 nearly parallel with Beacon street, and the character of the bed- 

 ding which could be seen in former years showed that no retreat 

 of the ice took place during the formation of the plain. 



Literature. 



Davis, W. M. — The subglacial origin of certain esliers. (Bos. Soc. 

 Nat. Hist., Proc, vol. 25, pp. 477-499.) 



Woodworth, J. B. — Some typical eskers of southern New England. 

 (Bos. Soc. Nat. Hist., Proc, vol. 26, pp. 197-220.) 



