MODIFIED DRIFT ALONG CONTOOCOOK RIVER. II3 



the channel here may have been formed by the erosion of the river. A 

 third of a milo from this railroad station, several parallel kamcs are found 

 extending nearly east and west between the highway and the outlet from 

 Rolfe's pond. These are composed of the usual water-worn gravel, v.dth 

 pebbles up to one foot in size, and form ridges and mounds 25 or 30 feet 

 high and 60 feet above the river. 



In the remaining ten miles of its course the Contoocook is almost con- 

 tinuously bordered by extensive low plains, seldom exceeding 30 feet 

 above the river, v/ith occasional areas of interval, but no kames were 

 seen. On the south side of the river, below West Hopkinton, portions of 

 these plains are 50 feet above the river ; and on the north side the same 

 height is reached by a delta-like deposit where the outlet from Clement 

 pond enters the alluvial area. At Contoocookville the alluvium is in- 

 terrupted by low areas of till or ledge, that upon the north side being 

 quite low and scarcely higher than the plains, which seem at the edge of 

 the village to extend across it. Thence eastward low sandy plains, from 

 15 to 25 feet above the Contoocook, extend nearly level for eight miles to 

 the Merrimack river. Their greatest expanse is in the north-east part of 

 Hopkinton, the north-west corner of Concord, and the south edge of 

 Webster, where they cover an area three miles long from north to south 

 and nearly two miles wide. This at the north consists partly of swampy 

 land, slightly depressed, and with no outlet for drainage. Warner and 

 Blackwater rivers, which are tributary to the Contoocook in Hopkinton, 

 are bordered by considerable alluvial deposits, the former in Warner and 

 the latter in Salisbury. 



Three miles above its mouth the Contoocook is enclosed by hills with 

 only a narrow alluvial margin. The proper continuity of its plain is here 

 along the Concord & Claremont Railroad, with a hill between it and the 

 river, east of which the plain is wide, lying principally on the south side 

 of the Contoocook river, at a height of 125 feet above the Merrimack. 

 Below Contoocookville the river has a height of about 355 feet above the 

 sea nearly to Fisherville, where it descends rapidly to its mouth, which is 

 249 feet above the sea. 



We will next consider the course of events in the Champlain period, of 

 which these deposits of modified drift bear witness. 

 VOL. III. 15 



