GLACIAL DRIFT. 



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south part of Deerfield descends to a large branch of the Lamprey river, and then rises 

 much towards the Centre. On both sides of this stream are lines of moraines parallel 

 with the brook, and also with the valley. These are excellent illustrations of this class 

 of moraines. How far these moraines would extend along the valley, can be known 

 only by further search. Our traverse is simply one section across them. Other exam- 

 ples occur in crossing the parallel tributary one mile south from the Centre. 



The hill north of Pawtuckaway pond in Nottingham, on the road nearest to and 

 around the mountain, shows lines of moraines parallel to the hill south-west from 

 Ouincy pond. Some of the blocks are 12 or 15 feet in length. 



In the north part of Fremont is a round hill less than 200 feet above the plain, around 

 which are local moraines, especially upon the north-west side. There is a large field 

 of big blocks near the Baptist church on the east side. The east and west road in the 

 north parts of Fremont and Brentwood lies over numerous drift ridges and moraines 

 essentially parallel with the stream and the higher land to the south. These may not 

 be local. 



In Kensington, the lenticular hills in the north-west part of the town show good 

 illustrations of the local moraines in the form of many rough blocks and small mounds 

 on the north-east side near M. Hobbs's. Some of the blocks are 20 feet long. This 

 example is of a large moraine deposit by the oldest drift, serving for the centre of 

 dispersion of blocks at the close of glacial work. 



South of the railroad at Raymond for two miles, chiefly east from the village, are 

 many moraines of all sizes, referred to local action, in case the high land to the north 

 is regarded as the locality from which they have come. They are as conspicuous as 

 most moraines left by the older drift. 



The foregoing are sufficiently numerous to call attention to the subject 

 of these late movements of earth analogous to glaciers. In this same 

 connection, I desire to describe certain other glacial phenomena of more 

 consequence, but which usually do not prove themselves by any striae or 

 embossment. They are better examples of ice action than what has just 

 been described, but like them, move down valleys and hillsides, smooth- 

 ing the ancient hill, and pushing along boulders. It is the action of gla- 

 ciers upon material that had already been moved by the continental ice, 

 and which belong to a later period still than the valley movements and 

 local glaciers. All these glacial movements are described here before 

 speaking of the boulders and moraines, so that the subject of glaciers 

 may be treated as a unity. This class of facts was first brought out by 

 the late Prof. L. Agassiz, who spent much time in their study about 

 Bethlehem. I had the pleasure of seeing the phenomena he describes, 

 under his guidance, and can testify to the fidelity of his statements. He 



